@@ -1,7 +1,4 @@
1{-# LANGUAGE ScopedTypeVariables #-}
1{-# LANGUAGE ScopedTypeVariables #-}
2−{-# LANGUAGE FlexibleInstances #-}
3−{-# LANGUAGE FlexibleContexts #-}
4−{-# LANGUAGE OverloadedStrings #-}
5module ProjectM36.RelationalExpression where
2module ProjectM36.RelationalExpression where
6import ProjectM36.Relation
3import ProjectM36.Relation
7import ProjectM36.Tuple
4import ProjectM36.Tuple
@@ -16,38 +13,32 @@ import ProjectM36.DataTypes.Primitive
16import ProjectM36.AtomFunction
13import ProjectM36.AtomFunction
17import ProjectM36.DatabaseContextFunction
14import ProjectM36.DatabaseContextFunction
18import ProjectM36.Arbitrary
15import ProjectM36.Arbitrary
19−import ProjectM36.GraphRefRelationalExpr
20import ProjectM36.Transaction
16import ProjectM36.Transaction
21import qualified ProjectM36.Attribute as A
17import qualified ProjectM36.Attribute as A
22import qualified Data.Map as M
18import qualified Data.Map as M
23import qualified Data.HashSet as HS
19import qualified Data.HashSet as HS
24import qualified Data.Set as S
20import qualified Data.Set as S
25−import Control.Monad.State hiding (join)
21+import Control.Monad.Trans.RWS.Strict as RWS hiding (join)
26−import Data.Bifunctor (second)
22+import Control.Monad.Trans.Class (lift)
23+import Control.Monad (forM)
24+import Control.Exception
27import Data.Maybe
25import Data.Maybe
28import Data.Either
26import Data.Either
29import Data.Char (isUpper)
27import Data.Char (isUpper)
31−import qualified Data.List.NonEmpty as NE
32−import Data.Functor.Identity
33import qualified Data.Text as T
28import qualified Data.Text as T
34import qualified Data.Vector as V
29import qualified Data.Vector as V
35import qualified ProjectM36.TypeConstructorDef as TCD
30import qualified ProjectM36.TypeConstructorDef as TCD
36−import qualified Control.Monad.RWS.Strict as RWS
31+import Control.Monad.Trans.Except
37−import Control.Monad.RWS.Strict (RWST, execRWST, runRWST)
38−import Control.Monad.Except hiding (join)
39−import Control.Monad.Trans.Except (except)
32+import Control.Monad.Trans.Reader as R
40−import Control.Monad.Reader as R hiding (join)
41−import ProjectM36.NormalizeExpr
42−import ProjectM36.WithNameExpr
43import Test.QuickCheck
33import Test.QuickCheck
44−import qualified Data.Functor.Foldable as Fold
34+import GHC
45−import Control.Applicative
46−#ifdef PM36_HASKELL_SCRIPTING
47−import GHC hiding (getContext)
48−import Control.Exception
49import GHC.Paths
35import GHC.Paths
50−#endif
36+import Data.Time.Clock
37+import Data.Time.Calendar
38+import qualified Data.List.NonEmpty as NE
39+import Data.Functor.Identity
41+import Control.Monad.IO.Class
52data DatabaseContextExprDetails = CountUpdatedTuples
43data DatabaseContextExprDetails = CountUpdatedTuples
@@ -75,52 +66,48 @@ mkDatabaseContextEvalState context = DatabaseContextEvalState {
75data RelationalExprEnv = RelationalExprEnv {
66data RelationalExprEnv = RelationalExprEnv {
76 re_context :: DatabaseContext,
67 re_context :: DatabaseContext,
77 re_graph :: TransactionGraph,
68 re_graph :: TransactionGraph,
69+ re_currentTransId :: TransactionId,
78 re_extra :: Maybe (Either RelationTuple Attributes)
70 re_extra :: Maybe (Either RelationTuple Attributes)
81−envTuple :: GraphRefRelationalExprEnv -> RelationTuple
73+stateTuple :: RelationalExprEnv -> RelationTuple
82−envTuple e = fromLeft emptyTuple (fromMaybe (Left emptyTuple) (gre_extra e))
74+stateTuple e = fromLeft emptyTuple (fromMaybe (Left emptyTuple) (re_extra e))
84−envAttributes :: GraphRefRelationalExprEnv -> Attributes
76+stateAttributes :: RelationalExprEnv -> Attributes
85−envAttributes e = fromRight emptyAttributes (fromMaybe (Right emptyAttributes) (gre_extra e))
77+stateAttributes e = fromRight emptyAttributes (fromMaybe (Right emptyAttributes) (re_extra e))
87instance Show RelationalExprEnv where
79instance Show RelationalExprEnv where
88 show e@RelationalExprEnv{} = "RelationalExprEnv " ++ show (re_extra e)
80 show e@RelationalExprEnv{} = "RelationalExprEnv " ++ show (re_extra e)
90−--used to eval relationalexpr
91−type RelationalExprM a = ReaderT RelationalExprEnv (ExceptT RelationalError Identity) a
93−runRelationalExprM :: RelationalExprEnv -> RelationalExprM a -> Either RelationalError a
94−runRelationalExprM env m = runIdentity (runExceptT (runReaderT m env))
96−reGraph :: RelationalExprM TransactionGraph
97−reGraph = asks re_graph
99−reContext :: RelationalExprM DatabaseContext
100−reContext = asks re_context
102−mkRelationalExprEnv :: DatabaseContext -> TransactionGraph -> RelationalExprEnv
82+mkRelationalExprEnv :: DatabaseContext -> TransactionId -> TransactionGraph -> RelationalExprEnv
103−mkRelationalExprEnv ctx graph =
83+mkRelationalExprEnv ctx currentTransId graph =
104 RelationalExprEnv
84 RelationalExprEnv
105 { re_context = ctx,
85 { re_context = ctx,
106 re_graph = graph,
86 re_graph = graph,
87+ re_currentTransId = currentTransId,
107 re_extra = Nothing }
88 re_extra = Nothing }
109−askEnv :: GraphRefRelationalExprM GraphRefRelationalExprEnv
90+askEnv :: RelationalExprState RelationalExprEnv
110askEnv = R.ask
91askEnv = R.ask
112−mergeTuplesIntoGraphRefRelationalExprEnv :: RelationTuple -> GraphRefRelationalExprEnv -> GraphRefRelationalExprEnv
93+currentTrans :: RelationalExprState (Either RelationalError Transaction)
113−mergeTuplesIntoGraphRefRelationalExprEnv tupIn env =
94+currentTrans = do
95+ tid <- re_currentTransId <$> R.ask
96+ graph <- re_graph <$> R.ask
97+ pure (transactionForId tid graph)
99+mergeTuplesIntoRelationalExprState :: RelationTuple -> RelationalExprEnv -> RelationalExprEnv
100+mergeTuplesIntoRelationalExprState tupIn e@RelationalExprEnv{} =
114− env { gre_extra = new_elems }
101+ e{re_extra = new_elems }
116 new_elems = Just (Left newTuple)
103 new_elems = Just (Left newTuple)
117− mergedTupMap = M.union (tupleToMap tupIn) (tupleToMap (envTuple env))
104+ mergedTupMap = M.union (tupleToMap tupIn) (tupleToMap (stateTuple e))
118 newTuple = mkRelationTupleFromMap mergedTupMap
105 newTuple = mkRelationTupleFromMap mergedTupMap
120−mergeAttributesIntoGraphRefRelationalExprEnv :: Attributes -> GraphRefRelationalExprEnv -> GraphRefRelationalExprEnv
107+mergeAttributesIntoRelationalExprState :: Attributes -> RelationalExprEnv -> RelationalExprEnv
121−mergeAttributesIntoGraphRefRelationalExprEnv attrsIn e = e { gre_extra = newattrs }
108+mergeAttributesIntoRelationalExprState attrsIn e@RelationalExprEnv{} = e{re_extra = newattrs }
123− newattrs = Just (Right (A.union attrsIn (envAttributes e)))
110+ newattrs = Just (Right (A.union attrsIn (stateAttributes e)))
125type ResultAccumName = StringType
112type ResultAccumName = StringType
@@ -142,12 +129,12 @@ data DatabaseContextEvalEnv = DatabaseContextEvalEnv
144mkDatabaseContextEvalEnv :: TransactionId -> TransactionGraph -> DatabaseContextEvalEnv
131mkDatabaseContextEvalEnv :: TransactionId -> TransactionGraph -> DatabaseContextEvalEnv
145−mkDatabaseContextEvalEnv = DatabaseContextEvalEnv
132+mkDatabaseContextEvalEnv tid graph = DatabaseContextEvalEnv tid graph
147type DatabaseContextEvalMonad a = RWST DatabaseContextEvalEnv () DatabaseContextEvalState (ExceptT RelationalError Identity) a
134type DatabaseContextEvalMonad a = RWST DatabaseContextEvalEnv () DatabaseContextEvalState (ExceptT RelationalError Identity) a
149runDatabaseContextEvalMonad :: DatabaseContext -> DatabaseContextEvalEnv -> DatabaseContextEvalMonad () -> Either RelationalError DatabaseContextEvalState
136runDatabaseContextEvalMonad :: DatabaseContext -> DatabaseContextEvalEnv -> DatabaseContextEvalMonad () -> Either RelationalError DatabaseContextEvalState
150−runDatabaseContextEvalMonad ctx env m = runIdentity (runExceptT (fst <$> execRWST m env freshEnv))
137+runDatabaseContextEvalMonad ctx env m = runIdentity (runExceptT (fst <$> (execRWST m env freshEnv)))
152 freshEnv = mkDatabaseContextEvalState ctx
139 freshEnv = mkDatabaseContextEvalState ctx
@@ -159,52 +146,20 @@ dbcGraph :: DatabaseContextEvalMonad TransactionGraph
159dbcGraph = dce_graph <$> RWS.ask
146dbcGraph = dce_graph <$> RWS.ask
161dbcRelationalExprEnv :: DatabaseContextEvalMonad RelationalExprEnv
148dbcRelationalExprEnv :: DatabaseContextEvalMonad RelationalExprEnv
162−dbcRelationalExprEnv =
149+dbcRelationalExprEnv = do
163− mkRelationalExprEnv <$> getStateContext <*> dbcGraph
152+ mkRelationalExprEnv <$> getStateContext <*> dbcTransId <*> dbcGraph
165getStateContext :: DatabaseContextEvalMonad DatabaseContext
154getStateContext :: DatabaseContextEvalMonad DatabaseContext
166−getStateContext = gets dbc_context
155+getStateContext = dbc_context <$> get
168putStateContext :: DatabaseContext -> DatabaseContextEvalMonad ()
157putStateContext :: DatabaseContext -> DatabaseContextEvalMonad ()
169putStateContext ctx' = do
158putStateContext ctx' = do
171− put (s {dbc_context = ctx', dbc_dirty = True})
160+ put (s {dbc_context = ctx'})
173−-- | The context is optionally passed down along in cases where the current context is uncommitted.
174−data GraphRefRelationalExprEnv =
175− GraphRefRelationalExprEnv {
176− gre_context :: Maybe DatabaseContext,
177− gre_graph :: TransactionGraph,
178− gre_extra :: Maybe (Either RelationTuple Attributes)
181−type GraphRefRelationalExprM a = ReaderT GraphRefRelationalExprEnv (ExceptT RelationalError Identity) a
162+type RelationalExprState a = Reader RelationalExprEnv a
183−gfTransForId :: TransactionId -> GraphRefRelationalExprM Transaction
184−gfTransForId tid = do
186− lift $ except $ transactionForId tid graph
188−gfDatabaseContextForMarker :: GraphRefTransactionMarker -> GraphRefRelationalExprM DatabaseContext
189−gfDatabaseContextForMarker (TransactionMarker transId) = concreteDatabaseContext <$> gfTransForId transId
190−gfDatabaseContextForMarker UncommittedContextMarker = do
191− mctx <- gre_context <$> askEnv
193− Nothing -> throwError NoUncommittedContextInEvalError
194− Just ctx -> pure ctx
196−runGraphRefRelationalExprM :: GraphRefRelationalExprEnv -> GraphRefRelationalExprM a -> Either RelationalError a
197−runGraphRefRelationalExprM env m = runIdentity (runExceptT (runReaderT m env))
199−freshGraphRefRelationalExprEnv :: Maybe DatabaseContext -> TransactionGraph -> GraphRefRelationalExprEnv
200−freshGraphRefRelationalExprEnv mctx graph = GraphRefRelationalExprEnv {
206−gfGraph :: GraphRefRelationalExprM TransactionGraph
207−gfGraph = asks gre_graph
209envContext :: RelationalExprEnv -> DatabaseContext
164envContext :: RelationalExprEnv -> DatabaseContext
210envContext = re_context
165envContext = re_context
@@ -212,27 +167,173 @@ envContext = re_context
212setEnvContext :: RelationalExprEnv -> DatabaseContext -> RelationalExprEnv
167setEnvContext :: RelationalExprEnv -> DatabaseContext -> RelationalExprEnv
213setEnvContext e ctx = e { re_context = ctx }
168setEnvContext e ctx = e { re_context = ctx }
171+--full evaluation down the graph
172+eval :: RelationalExpr -> RelationalExprState (Either RelationalError Relation)
175+ eGfExpr <- processRelationalExpr expr
177+ Left err -> pure (Left err)
178+ Right gfExpr -> pure $ evalGraphRefRelationalExpr gfExpr (re_graph env)
181+--relvar state is needed in evaluation of relational expression but only as read-only in order to extract current relvar values
182+evalRelationalExpr :: RelationalExpr -> RelationalExprState (Either RelationalError GraphRefRelationalExpr)
183+evalRelationalExpr (RelationVariable name _) = do
184+ relvarTable <- fmap (relationVariables . envContext) askEnv
185+ return $ case M.lookup name relvarTable of
186+ Just res -> Right res
187+ Nothing -> Left $ RelVarNotDefinedError name
189+evalRelationalExpr (Project attrNames expr) = do
190+ eAttrNameSet <- evalAttributeNames attrNames expr
191+ case eAttrNameSet of
192+ Left err -> pure (Left err)
193+ Right attrNameSet -> do
194+ rel <- evalRelationalExpr expr
196+ Right rel2 -> pure $ Right (Project (AttributeNames attrNameSet) rel2)
197+ Left err -> pure $ Left err
199+evalRelationalExpr (Union exprA exprB) = do
200+ relA <- evalRelationalExpr exprA
201+ relB <- evalRelationalExpr exprB
203+ Left err -> return $ Left err
204+ Right relA2 -> case relB of
205+ Left err -> return $ Left err
206+ Right relB2 -> return $ Right (Union relA2 relB2)
208+evalRelationalExpr (Join exprA exprB) = do
209+ relA <- evalRelationalExpr exprA
210+ relB <- evalRelationalExpr exprB
212+ Left err -> return $ Left err
213+ Right relA2 -> case relB of
214+ Left err -> return $ Left err
215+ Right relB2 -> return $ Right (Join relA2 relB2)
217+evalRelationalExpr (Difference exprA exprB) = do
218+ relA <- evalRelationalExpr exprA
219+ relB <- evalRelationalExpr exprB
221+ Left err -> return $ Left err
222+ Right relA2 -> case relB of
223+ Left err -> return $ Left err
224+ Right relB2 -> return $ Right (Difference relA2 relB2)
226+evalRelationalExpr (MakeStaticRelation attributeSet tupleSet) =
227+ case mkRelation attributeSet tupleSet of
228+ Right rel -> return $ Right (ExistingRelation rel)
229+ Left err -> return $ Left err
231+evalRelationalExpr (MakeRelationFromExprs mAttrExprs tupleExprs) = do
232+ currentContext <- fmap envContext askEnv
233+ let tConss = typeConstructorMapping currentContext
234+ -- if the mAttrExprs is Nothing, then we should attempt to infer the tuple attributes from the first tuple itself- note that this is not always possible
236+ mAttrs <- case mAttrExprs of
238+ Just . A.attributesFromList <$> mapM evalGraphRefAttrExpr (fromMaybe [] mAttrExprs)
239+ Nothing -> pure Nothing
240+ tuples <- mapM (liftE . evalTupleExpr mAttrs) tupleExprs
241+ let attrs = fromMaybe firstTupleAttrs mAttrs
242+ firstTupleAttrs = if null tuples then A.emptyAttributes else tupleAttributes (head tuples)
243+ expr <- either throwE pure (mkRelation attrs (RelationTupleSet tuples))
244+ pure (ExistingRelation expr)
246+evalRelationalExpr (ExistingRelation rel) = pure (Right (ExistingRelation rel))
248+evalRelationalExpr (Rename oldAttrName newAttrName relExpr) = do
249+ evald <- evalRelationalExpr relExpr
251+ Right expr -> return $ Right (Rename oldAttrName newAttrName expr)
252+ Left err -> return $ Left err
254+evalRelationalExpr (Group oldAttrNames newAttrName relExpr) = do
255+ eOldAttrNameSet <- evalAttributeNames oldAttrNames relExpr
256+ case eOldAttrNameSet of
257+ Left err -> pure (Left err)
258+ Right oldAttrNameSet -> do
259+ evald <- evalRelationalExpr relExpr
261+ Right expr -> return $ Right (Group (AttributeNames oldAttrNameSet) newAttrName expr)
262+ Left err -> return $ Left err
264+evalRelationalExpr (Ungroup attrName relExpr) = do
265+ evald <- evalRelationalExpr relExpr
267+ Right expr -> return $ Right (Ungroup attrName expr)
268+ Left err -> return $ Left err
270+evalRelationalExpr (Restrict predicateExpr relExpr) = do
271+ evald <- evalRelationalExpr relExpr
272+ pred <- processRestrictionPredicateExpr predicateExpr
274+ Left err -> return $ Left err
276+ pure $ Right (Restrict pred expr)
278+evalRelationalExpr (Equals relExprA relExprB) = do
279+ evaldA <- evalRelationalExpr relExprA
280+ evaldB <- evalRelationalExpr relExprB
282+ Left err -> return $ Left err
283+ Right exprA -> case evaldB of
284+ Left err -> return $ Left err
285+ Right exprB -> return $ Right (Equals exprA exprB)
287+evalRelationalExpr (With views mainExpr) = do
290+ let addScopedView ctx (vname,vexpr) = if vname `M.member` relationVariables ctx then
291+ Left (RelVarAlreadyDefinedError vname)
293+ case runState (evalDatabaseContextExpr (Assign vname vexpr)) (freshDatabaseState ctx) of
294+ (Left err,_) -> Left err
295+ (Right (), (ctx',_,_)) -> Right ctx'
297+ case foldM addScopedView (stateElemsContext rstate) views of
298+ Left err -> return $ Left err
300+ let evalMainExpr expr = runReader (evalRelationalExpr expr) (RelationalExprEnv ctx'')
301+ case evalMainExpr mainExpr of
302+ Left err -> return $ Left err
303+ Right rel -> return $ Right rel
305+--warning: copy-pasta from above- refactor
306+evalRelationalExpr (NotEquals relExprA relExprB) = do
307+ evaldA <- evalRelationalExpr relExprA
308+ evaldB <- evalRelationalExpr relExprB
310+ Left err -> return $ Left err
311+ Right exprA -> case evaldB of
312+ Left err -> return $ Left err
313+ Right exprB -> return $ Right (NotEquals exprA exprB)
315+-- extending a relation adds a single attribute with the results of the per-tuple expression evaluated
316+evalRelationalExpr (Extend tupleExpression relExpr) = do
317+ eExpr <- evalRelationalExpr relExpr
319+ Left err -> pure (Left err)
321+ tupProc <- processExtendTupleExpr tupleExpression
322+ pure (Right (Extend tupProc expr))
215--helper function to process relation variable creation/assignment
324--helper function to process relation variable creation/assignment
216setRelVar :: RelVarName -> GraphRefRelationalExpr -> DatabaseContextEvalMonad ()
325setRelVar :: RelVarName -> GraphRefRelationalExpr -> DatabaseContextEvalMonad ()
217setRelVar relVarName relExpr = do
326setRelVar relVarName relExpr = do
218 currentContext <- getStateContext
328 currentContext <- getStateContext
219− --prevent recursive relvar definition by resolving references to relvars in previous states
220− relExpr' <- resolve relExpr
221− let newRelVars = M.insert relVarName relExpr' $ relationVariables currentContext
329+ let newRelVars = M.insert relVarName relExpr $ relationVariables currentContext
222 potentialContext = currentContext { relationVariables = newRelVars }
330 potentialContext = currentContext { relationVariables = newRelVars }
223− --optimization: if the relexpr is unchanged, skip the update
224− if M.lookup relVarName (relationVariables currentContext) == Just relExpr then
227− --determine when to check constraints
331+ --determine when to check constraints
228− graph <- dbcGraph
332+ graph <- dbcGraph
229− tid <- dbcTransId
333+ tid <- dbcTransId
230− case checkConstraints potentialContext tid graph of
334+ case checkConstraints potentialContext tid graph of
231− Left err -> dbErr err
335+ Left err -> dbErr err
232− Right _ -> putStateContext potentialContext
336+ Right _ -> putStateContext potentialContext
234−--fast-path insertion- we already know that the previous relvar validated correctly, so we can validate just the relation that is being inserted for attribute matches- without this, even a single tuple relation inserted causes the entire relation to be re-validated unnecessarily
235−--insertIntoRelVar :: RelVarName -> GraphRefRelationalExpr -> DatabaseContextEvalMonad ()
237-- it is not an error to delete a relvar which does not exist, just like it is not an error to insert a pre-existing tuple into a relation
338-- it is not an error to delete a relvar which does not exist, just like it is not an error to insert a pre-existing tuple into a relation
238deleteRelVar :: RelVarName -> DatabaseContextEvalMonad ()
339deleteRelVar :: RelVarName -> DatabaseContextEvalMonad ()
@@ -251,17 +352,20 @@ evalGraphRefDatabaseContextExpr :: GraphRefDatabaseContextExpr -> DatabaseContex
251evalGraphRefDatabaseContextExpr NoOperation = pure ()
352evalGraphRefDatabaseContextExpr NoOperation = pure ()
253evalGraphRefDatabaseContextExpr (Define relVarName attrExprs) = do
354evalGraphRefDatabaseContextExpr (Define relVarName attrExprs) = do
254− context <- getStateContext
255 relvars <- fmap relationVariables getStateContext
355 relvars <- fmap relationVariables getStateContext
256 tConss <- fmap typeConstructorMapping getStateContext
356 tConss <- fmap typeConstructorMapping getStateContext
257− graph <- dbcGraph
357+ relEnv <- dbcRelationalExprEnv
258− let eAttrs = runGraphRefRelationalExprM gfEnv (mapM evalGraphRefAttrExpr attrExprs)
358+ let eAttrs = runReader (mapM evalGraphRefAttrExpr attrExprs) relEnv
259− gfEnv = freshGraphRefRelationalExprEnv (Just context) graph
359+ attrErrs = lefts eAttrs
260− case eAttrs of
360+ attrsList = rights eAttrs
261− Left err -> dbErr err
361+ if not (null attrErrs) then
262− Right attrsList -> do
362+ dbErr (someErrors attrErrs)
263− lift $ except $ validateAttributes tConss (A.attributesFromList attrsList)
363+ else do
364+ let atomTypeErrs = lefts $ map ((`validateAtomType` tConss) . A.atomType) attrsList
365+ if not (null atomTypeErrs) then
366+ dbErr (someErrors atomTypeErrs)
264− case M.member relVarName relvars of
368+ case M.member relVarName relvars of
265 True -> dbErr (RelVarAlreadyDefinedError relVarName)
369 True -> dbErr (RelVarAlreadyDefinedError relVarName)
266 False -> setRelVar relVarName (ExistingRelation emptyRelation)
370 False -> setRelVar relVarName (ExistingRelation emptyRelation)
@@ -271,20 +375,15 @@ evalGraphRefDatabaseContextExpr (Define relVarName attrExprs) = do
271evalGraphRefDatabaseContextExpr (Undefine relVarName) = deleteRelVar relVarName
375evalGraphRefDatabaseContextExpr (Undefine relVarName) = deleteRelVar relVarName
273evalGraphRefDatabaseContextExpr (Assign relVarName expr) = do
377evalGraphRefDatabaseContextExpr (Assign relVarName expr) = do
274− graph <- re_graph <$> dbcRelationalExprEnv
378+ relExprEnv <- dbcRelationalExprEnv
275 context <- getStateContext
379 context <- getStateContext
276 let existingRelVar = M.lookup relVarName (relationVariables context)
380 let existingRelVar = M.lookup relVarName (relationVariables context)
277− reEnv = freshGraphRefRelationalExprEnv (Just context) graph
278− eNewExprType = runGraphRefRelationalExprM reEnv (typeForGraphRefRelationalExpr expr)
279 case existingRelVar of
381 case existingRelVar of
280 Nothing -> do
382 Nothing -> do
281− case runGraphRefRelationalExprM reEnv (typeForGraphRefRelationalExpr expr) of
282− Left err -> dbErr err
284− lift $ except $ validateAttributes (typeConstructorMapping context) (attributes reltype)
285− setRelVar relVarName expr
383+ setRelVar relVarName expr
286 Just existingRel -> do
384 Just existingRel -> do
287− let eExpectedType = runGraphRefRelationalExprM reEnv (typeForGraphRefRelationalExpr existingRel)
385+ let eExpectedType = runReader (typeForGraphRefRelationalExpr existingRel) relExprEnv
386+ eNewExprType = runReader (typeForGraphRefRelationalExpr expr) relExprEnv
288 case eExpectedType of
387 case eExpectedType of
289 Left err -> dbErr err
388 Left err -> dbErr err
290 Right expectedType ->
389 Right expectedType ->
@@ -292,53 +391,44 @@ evalGraphRefDatabaseContextExpr (Assign relVarName expr) = do
292 Left err -> dbErr err
391 Left err -> dbErr err
293 Right newExprType -> do
392 Right newExprType -> do
294 if newExprType == expectedType then do
393 if newExprType == expectedType then do
295− lift $ except $ validateAttributes (typeConstructorMapping context) (attributes newExprType)
296 setRelVar relVarName expr
394 setRelVar relVarName expr
298 dbErr (RelationTypeMismatchError (attributes expectedType) (attributes newExprType))
396 dbErr (RelationTypeMismatchError (attributes expectedType) (attributes newExprType))
300evalGraphRefDatabaseContextExpr (Insert relVarName relExpr) = do
398evalGraphRefDatabaseContextExpr (Insert relVarName relExpr) = do
301− gfExpr <- relVarByName relVarName
399+ transId <- dbcTransId
302− let optExpr = applyUnionCollapse (Union
305− evalGraphRefDatabaseContextExpr (Assign relVarName optExpr)
400+ evalGraphRefDatabaseContextExpr (Assign relVarName
402+ (RelationVariable relVarName transId)
307evalGraphRefDatabaseContextExpr (Delete relVarName predicate) = do
405evalGraphRefDatabaseContextExpr (Delete relVarName predicate) = do
308− gfExpr <- relVarByName relVarName
406+ transId <- dbcTransId
407+ let rv = RelationVariable relVarName transId
309− let optExpr = applyRestrictionCollapse (Restrict (NotPredicate predicate) gfExpr)
408+ setRelVar relVarName (Restrict (NotPredicate predicate) rv)
310− setRelVar relVarName optExpr
312--union of restricted+updated portion and the unrestricted+unupdated portion
410--union of restricted+updated portion and the unrestricted+unupdated portion
313−evalGraphRefDatabaseContextExpr (Update relVarName atomExprMap pred') = do
411+evalGraphRefDatabaseContextExpr (Update relVarName atomExprMap pred) = do
314− rvExpr <- relVarByName relVarName
315− graph <- re_graph <$> dbcRelationalExprEnv
316 context <- getStateContext
412 context <- getStateContext
317− let reEnv = freshGraphRefRelationalExprEnv (Just context) graph
413+ transId <- dbcTransId
318− --get the current attributes name in the relvar to ensure that we don't conflict when renaming
414+ reEnv <- dbcRelationalExprEnv
319− eExprType = runGraphRefRelationalExprM reEnv (typeForGraphRefRelationalExpr rvExpr)
415+ let relVarMap = relationVariables context
320− exprType' <- case eExprType of
416+ case M.lookup relVarName relVarMap of
321− Left err -> throwError err
417+ Nothing -> dbErr (RelVarNotDefinedError relVarName)
322− Right t -> pure t
418+ Just existingRvExpr -> do
323− let unrestrictedPortion = Restrict (NotPredicate pred') rvExpr
419+ let unrestrictedPortion = Restrict (NotPredicate pred) rv
324− tmpAttr = tmpAttrC 1
420+ rv = RelationVariable relVarName transId
325− tmpAttrC :: Int -> AttributeName -> AttributeName
421+ tmpAttr attr = "_tmp_" <> attr --this could certainly be improved to verify that there is no attribute name conflict
327− let tmpAttrName = "_tmp_" <> T.pack (show c) <> attr in
328− if tmpAttrName `S.member` A.attributeNameSet (attributes exprType') then
332− updateAttr nam atomExpr = Extend (AttributeExtendTupleExpr (tmpAttr nam) atomExpr)
422+ updateAttr nam atomExpr = Extend (AttributeExtendTupleExpr (tmpAttr nam) atomExpr)
333− projectAndRename attr expr = Rename (tmpAttr attr) attr (Project (InvertedAttributeNames (S.singleton attr)) expr)
423+ projectAndRename attr expr = Rename (tmpAttr attr) attr (Project (InvertedAttributeNames (S.singleton attr)) expr)
334− restrictedPortion = Restrict pred' rvExpr
424+ restrictedPortion = Restrict pred
335− updated = foldr (\(oldname, atomExpr) accum ->
425+ updated = foldr (\(oldname, atomExpr) accum ->
336− let procAtomExpr = runProcessExprM UncommittedContextMarker (processAtomExpr atomExpr) in
426+ let procAtomExpr = runReader (processAtomExpr atomExpr) reEnv in
337 updateAttr oldname procAtomExpr accum
427 updateAttr oldname procAtomExpr accum
338− ) restrictedPortion (M.toList atomExprMap)
428+ ) rv (M.toList atomExprMap)
339 -- the atomExprMap could reference other attributes, so we must perform multi-pass folds
429 -- the atomExprMap could reference other attributes, so we must perform multi-pass folds
340− updatedPortion = foldr projectAndRename updated (M.keys atomExprMap)
430+ updatedPortion = foldr projectAndRename updated (M.keys atomExprMap)
341− setRelVar relVarName (Union unrestrictedPortion updatedPortion)
431+ setRelVar relVarName (Union unrestrictedPortion updatedPortion)
343evalGraphRefDatabaseContextExpr (AddInclusionDependency newDepName newDep) = do
433evalGraphRefDatabaseContextExpr (AddInclusionDependency newDepName newDep) = do
344 currContext <- getStateContext
434 currContext <- getStateContext
@@ -350,8 +440,6 @@ evalGraphRefDatabaseContextExpr (AddInclusionDependency newDepName newDep) = do
350 dbErr (InclusionDependencyNameInUseError newDepName)
440 dbErr (InclusionDependencyNameInUseError newDepName)
352 let potentialContext = currContext { inclusionDependencies = newDeps }
442 let potentialContext = currContext { inclusionDependencies = newDeps }
353− -- if the potential context passes all constraints, then save it
354− -- potential optimization: validate only the new constraint- all old constraints must already hold
355 case checkConstraints potentialContext transId graph of
443 case checkConstraints potentialContext transId graph of
356 Left err -> dbErr err
444 Left err -> dbErr err
357 Right _ ->
445 Right _ ->
@@ -396,9 +484,9 @@ evalGraphRefDatabaseContextExpr (AddTypeConstructor tConsDef dConsDefList) = do
396 let oldTypes = typeConstructorMapping currentContext
484 let oldTypes = typeConstructorMapping currentContext
397 tConsName = TCD.name tConsDef
485 tConsName = TCD.name tConsDef
398 -- validate that the constructor's types exist
486 -- validate that the constructor's types exist
399− case validateTypeConstructorDef tConsDef dConsDefList oldTypes of
487+ case validateTypeConstructorDef tConsDef dConsDefList of
400− Left err -> throwError err
488+ errs@(_:_) -> dbErr (someErrors errs)
401− Right () | T.null tConsName || not (isUpper (T.head tConsName)) -> dbErr (InvalidAtomTypeName tConsName)
489+ [] | T.null tConsName || not (isUpper (T.head tConsName)) -> dbErr (InvalidAtomTypeName tConsName)
402 | isJust (findTypeConstructor tConsName oldTypes) -> dbErr (AtomTypeNameInUseError tConsName)
490 | isJust (findTypeConstructor tConsName oldTypes) -> dbErr (AtomTypeNameInUseError tConsName)
403 | otherwise -> do
491 | otherwise -> do
404 let newTypes = oldTypes ++ [(tConsDef, dConsDefList)]
492 let newTypes = oldTypes ++ [(tConsDef, dConsDefList)]
@@ -414,10 +502,15 @@ evalGraphRefDatabaseContextExpr (RemoveTypeConstructor tConsName) = do
414 let newTypes = filter (\(tCons, _) -> TCD.name tCons /= tConsName) oldTypes
502 let newTypes = filter (\(tCons, _) -> TCD.name tCons /= tConsName) oldTypes
415 putStateContext $ currentContext { typeConstructorMapping = newTypes }
503 putStateContext $ currentContext { typeConstructorMapping = newTypes }
417−evalGraphRefDatabaseContextExpr (MultipleExpr exprs) =
505+evalGraphRefDatabaseContextExpr (MultipleExpr exprs) = do
418 --the multiple expressions must pass the same context around- not the old unmodified context
506 --the multiple expressions must pass the same context around- not the old unmodified context
419− mapM_ evalGraphRefDatabaseContextExpr exprs
508+{- evald <- forM exprs (\expr -> evalGraphRefDatabaseContextExpr expr)
420−
509+ --some lifting magic needed here
512+ errs -> dbErr (someErrors errs)
421evalGraphRefDatabaseContextExpr (RemoveAtomFunction funcName) = do
514evalGraphRefDatabaseContextExpr (RemoveAtomFunction funcName) = do
422 currentContext <- getStateContext
515 currentContext <- getStateContext
423 let atomFuncs = atomFunctions currentContext
516 let atomFuncs = atomFunctions currentContext
@@ -444,11 +537,10 @@ evalGraphRefDatabaseContextExpr (RemoveDatabaseContextFunction funcName) = do
445evalGraphRefDatabaseContextExpr (ExecuteDatabaseContextFunction funcName atomArgExprs) = do
538evalGraphRefDatabaseContextExpr (ExecuteDatabaseContextFunction funcName atomArgExprs) = do
446 context <- getStateContext
539 context <- getStateContext
447− graph <- dbcGraph
540+ relExprEnv <- dbcRelationalExprEnv
448 --resolve atom arguments
541 --resolve atom arguments
449− let eAtomTypes = mapM (runGraphRefRelationalExprM gfEnv . typeForGraphRefAtomExpr emptyAttributes) atomArgExprs
542+ let eAtomTypes = map (\atomExpr -> runReader (typeForGraphRefAtomExpr emptyAttributes atomExpr) relExprEnv) atomArgExprs
450 eFunc = databaseContextFunctionForName funcName (dbcFunctions context)
543 eFunc = databaseContextFunctionForName funcName (dbcFunctions context)
451− gfEnv = freshGraphRefRelationalExprEnv (Just context) graph
452 case eFunc of
544 case eFunc of
453 Left err -> dbErr err
545 Left err -> dbErr err
454 Right func -> do
546 Right func -> do
@@ -458,16 +550,16 @@ evalGraphRefDatabaseContextExpr (ExecuteDatabaseContextFunction funcName atomArg
458 dbErr (FunctionArgumentCountMismatchError expectedArgCount actualArgCount)
550 dbErr (FunctionArgumentCountMismatchError expectedArgCount actualArgCount)
460 --check that the atom types are valid
552 --check that the atom types are valid
461− case eAtomTypes of
553+ case lefts eAtomTypes of
462− Left err -> dbErr err
554+ _:_ -> dbErr (someErrors (lefts eAtomTypes))
463− Right atomTypes -> do
555+ [] -> do
464− let mValidTypes = zipWith (\ expType actType
556+ let atomTypes = rights eAtomTypes
465− -> case atomTypeVerify expType actType of
557+ let mValidTypes = map (\(expType, actType) -> case atomTypeVerify expType actType of
466− Left err -> Just err
558+ Left err -> Just err
468− (dbcFuncType func) atomTypes
559+ Right _ -> Nothing) (zip (dbcFuncType func) atomTypes)
469 typeErrors = catMaybes mValidTypes
560 typeErrors = catMaybes mValidTypes
470− eAtomArgs = map (runGraphRefRelationalExprM gfEnv . evalGraphRefAtomExpr emptyTuple) atomArgExprs
561+ eAtomArgs = unimplemented
562+ --eAtomArgs = map (\arg -> runReader (evalAtomExpr emptyTuple arg) relExprState) atomArgExprs
471 if length (lefts eAtomArgs) > 1 then
563 if length (lefts eAtomArgs) > 1 then
472 dbErr (someErrors (lefts eAtomArgs))
564 dbErr (someErrors (lefts eAtomArgs))
473 else if not (null typeErrors) then
565 else if not (null typeErrors) then
@@ -476,6 +568,7 @@ evalGraphRefDatabaseContextExpr (ExecuteDatabaseContextFunction funcName atomArg
476 case evalDatabaseContextFunction func (rights eAtomArgs) context of
568 case evalDatabaseContextFunction func (rights eAtomArgs) context of
477 Left err -> dbErr err
569 Left err -> dbErr err
478 Right newContext -> putStateContext newContext
570 Right newContext -> putStateContext newContext
479data DatabaseContextIOEvalEnv = DatabaseContextIOEvalEnv
572data DatabaseContextIOEvalEnv = DatabaseContextIOEvalEnv
480 { dbcio_transId :: TransactionId,
573 { dbcio_transId :: TransactionId,
481 dbcio_graph :: TransactionGraph,
574 dbcio_graph :: TransactionGraph,
@@ -484,15 +577,6 @@ data DatabaseContextIOEvalEnv = DatabaseContextIOEvalEnv
485type DatabaseContextIOEvalMonad a = RWST DatabaseContextIOEvalEnv () DatabaseContextEvalState IO a
578type DatabaseContextIOEvalMonad a = RWST DatabaseContextIOEvalEnv () DatabaseContextEvalState IO a
487−runDatabaseContextIOEvalMonad :: DatabaseContextIOEvalEnv -> DatabaseContext -> DatabaseContextIOEvalMonad (Either RelationalError ()) -> IO (Either RelationalError DatabaseContextEvalState)
488−runDatabaseContextIOEvalMonad env ctx m = do
489− res <- runRWST m env freshState
491− (Left err,_,_) -> pure (Left err)
492− (Right (),s,_) -> pure (Right s)
494− freshState = mkDatabaseContextEvalState ctx
496requireScriptSession :: DatabaseContextIOEvalMonad (Either RelationalError ScriptSession)
580requireScriptSession :: DatabaseContextIOEvalMonad (Either RelationalError ScriptSession)
497requireScriptSession = do
581requireScriptSession = do
498 env <- RWS.ask
582 env <- RWS.ask
@@ -511,15 +595,10 @@ getDBCIOContext = dbc_context <$> RWS.get
511getDBCIORelationalExprEnv :: DatabaseContextIOEvalMonad RelationalExprEnv
595getDBCIORelationalExprEnv :: DatabaseContextIOEvalMonad RelationalExprEnv
512getDBCIORelationalExprEnv = do
596getDBCIORelationalExprEnv = do
513 context <- getDBCIOContext
597 context <- getDBCIOContext
514− mkRelationalExprEnv context . dbcio_graph <$> RWS.ask
599+ pure $ mkRelationalExprEnv context (dbcio_transId env) (dbcio_graph env)
516evalGraphRefDatabaseContextIOExpr :: GraphRefDatabaseContextIOExpr -> DatabaseContextIOEvalMonad (Either RelationalError ())
601evalGraphRefDatabaseContextIOExpr :: GraphRefDatabaseContextIOExpr -> DatabaseContextIOEvalMonad (Either RelationalError ())
517−#if !defined(PM36_HASKELL_SCRIPTING)
518−evalGraphRefDatabaseContextIOExpr AddAtomFunction{} = pure (Left (ScriptError ScriptCompilationDisabledError))
519−evalGraphRefDatabaseContextIOExpr AddDatabaseContextFunction{} = pure (Left (ScriptError ScriptCompilationDisabledError))
520−evalGraphRefDatabaseContextIOExpr LoadAtomFunctions{} = pure (Left (ScriptError ScriptCompilationDisabledError))
521−evalGraphRefDatabaseContextIOExpr LoadDatabaseContextFunctions{} = pure (Left (ScriptError ScriptCompilationDisabledError))
523evalGraphRefDatabaseContextIOExpr (AddAtomFunction funcName funcType script) = do
602evalGraphRefDatabaseContextIOExpr (AddAtomFunction funcName funcType script) = do
524 eScriptSession <- requireScriptSession
603 eScriptSession <- requireScriptSession
525 currentContext <- getDBCIOContext
604 currentContext <- getDBCIOContext
@@ -553,6 +632,7 @@ evalGraphRefDatabaseContextIOExpr (AddAtomFunction funcName funcType script) = d
553 Right eContext -> case eContext of
632 Right eContext -> case eContext of
554 Left err -> pure (Left err)
633 Left err -> pure (Left err)
555 Right context' -> putDBCIOContext context'
634 Right context' -> putDBCIOContext context'
556evalGraphRefDatabaseContextIOExpr (AddDatabaseContextFunction funcName funcType script) = do
636evalGraphRefDatabaseContextIOExpr (AddDatabaseContextFunction funcName funcType script) = do
557 eScriptSession <- requireScriptSession
637 eScriptSession <- requireScriptSession
558 currentContext <- getDBCIOContext
638 currentContext <- getDBCIOContext
@@ -594,6 +674,7 @@ evalGraphRefDatabaseContextIOExpr (AddDatabaseContextFunction funcName funcType
594 Right eContext -> case eContext of
674 Right eContext -> case eContext of
595 Left err -> pure (Left err)
675 Left err -> pure (Left err)
596 Right context' -> putDBCIOContext context'
676 Right context' -> putDBCIOContext context'
597evalGraphRefDatabaseContextIOExpr (LoadAtomFunctions modName funcName modPath) = do
678evalGraphRefDatabaseContextIOExpr (LoadAtomFunctions modName funcName modPath) = do
598 currentContext <- getDBCIOContext
679 currentContext <- getDBCIOContext
599 eLoadFunc <- liftIO $ loadAtomFunctions (T.unpack modName) (T.unpack funcName) modPath
680 eLoadFunc <- liftIO $ loadAtomFunctions (T.unpack modName) (T.unpack funcName) modPath
@@ -610,7 +691,7 @@ evalGraphRefDatabaseContextIOExpr (LoadDatabaseContextFunctions modName funcName
610 Right dbcListFunc -> let newContext = currentContext { dbcFunctions = mergedFuncs }
691 Right dbcListFunc -> let newContext = currentContext { dbcFunctions = mergedFuncs }
611 mergedFuncs = HS.union (dbcFunctions currentContext) (HS.fromList dbcListFunc)
692 mergedFuncs = HS.union (dbcFunctions currentContext) (HS.fromList dbcListFunc)
612 in putDBCIOContext newContext
693 in putDBCIOContext newContext
614evalGraphRefDatabaseContextIOExpr (CreateArbitraryRelation relVarName attrExprs range) = do
695evalGraphRefDatabaseContextIOExpr (CreateArbitraryRelation relVarName attrExprs range) = do
616 currentContext <- getDBCIOContext
697 currentContext <- getDBCIOContext
@@ -618,61 +699,63 @@ evalGraphRefDatabaseContextIOExpr (CreateArbitraryRelation relVarName attrExprs
618 --create graph ref expr
699 --create graph ref expr
619 let gfExpr = Define relVarName attrExprs
700 let gfExpr = Define relVarName attrExprs
620 evalEnv = mkDatabaseContextEvalEnv (dbcio_transId env) (dbcio_graph env)
701 evalEnv = mkDatabaseContextEvalEnv (dbcio_transId env) (dbcio_graph env)
702+ transId = dbcio_transId env
621 graph = dbcio_graph env
703 graph = dbcio_graph env
622 case runDatabaseContextEvalMonad currentContext evalEnv (evalGraphRefDatabaseContextExpr gfExpr) of
704 case runDatabaseContextEvalMonad currentContext evalEnv (evalGraphRefDatabaseContextExpr gfExpr) of
623 Left err -> pure (Left err)
705 Left err -> pure (Left err)
624− Right dbstate -> do
706+ Right state -> do
626 let existingRelVar = M.lookup relVarName relVarTable
708 let existingRelVar = M.lookup relVarName relVarTable
627− relVarTable = relationVariables (dbc_context dbstate)
709+ relVarTable = relationVariables (dbc_context state)
628 case existingRelVar of
710 case existingRelVar of
629 Nothing -> pure $ Left (RelVarNotDefinedError relVarName)
711 Nothing -> pure $ Left (RelVarNotDefinedError relVarName)
630 Just existingRel -> do
712 Just existingRel -> do
631− let gfEnv = freshGraphRefRelationalExprEnv (Just currentContext) graph
632− case runGraphRefRelationalExprM gfEnv (typeForGraphRefRelationalExpr existingRel) of
713+ case runReader (typeForGraphRefRelationalExpr existingRel) (mkRelationalExprEnv currentContext transId graph) of
633 Left err -> pure (Left err)
714 Left err -> pure (Left err)
634 Right relType -> do
715 Right relType -> do
635 let expectedAttributes = attributes relType
716 let expectedAttributes = attributes relType
636− tcMap = typeConstructorMapping (dbc_context dbstate)
717+ tcMap = typeConstructorMapping (dbc_context state)
637 eitherRel <- liftIO $ generate $ runReaderT (arbitraryRelation expectedAttributes range) tcMap
718 eitherRel <- liftIO $ generate $ runReaderT (arbitraryRelation expectedAttributes range) tcMap
638 case eitherRel of
719 case eitherRel of
639 Left err -> pure $ Left err
720 Left err -> pure $ Left err
640 Right rel ->
721 Right rel ->
641 case runDatabaseContextEvalMonad currentContext evalEnv (setRelVar relVarName (ExistingRelation rel)) of
722 case runDatabaseContextEvalMonad currentContext evalEnv (setRelVar relVarName (ExistingRelation rel)) of
642 Left err -> pure (Left err)
723 Left err -> pure (Left err)
643− Right dbstate' -> putDBCIOContext (dbc_context dbstate')
724+ Right state -> putDBCIOContext (dbc_context state)
726+updateTupleWithAtomExprs :: M.Map AttributeName AtomExpr -> DatabaseContext -> TransactionGraph -> RelationTuple -> Either RelationalError RelationTuple
727+updateTupleWithAtomExprs exprMap context graph tupIn = do
728+ --resolve all atom exprs
729+ atomsAssoc <- mapM (\(attrName, atomExpr) -> do
730+ let atom = unimplemented
731+ --atom <- runReader (evalAtomExpr tupIn atomExpr) (mkRelationalExprState context graph)
732+ pure (attrName, atom)
733+ ) (M.toList exprMap)
734+ pure (updateTupleWithAtoms (M.fromList atomsAssoc) tupIn)
645--run verification on all constraints
736--run verification on all constraints
646checkConstraints :: DatabaseContext -> TransactionId -> TransactionGraph -> Either RelationalError ()
737checkConstraints :: DatabaseContext -> TransactionId -> TransactionGraph -> Either RelationalError ()
647−checkConstraints context transId graph@(TransactionGraph graphHeads transSet) = do
738+checkConstraints context transId graph@(TransactionGraph graphHeads transSet) =
648 mapM_ (uncurry checkIncDep) (M.toList deps)
739 mapM_ (uncurry checkIncDep) (M.toList deps)
650 potentialGraph = TransactionGraph graphHeads (S.insert tempTrans transSet)
741 potentialGraph = TransactionGraph graphHeads (S.insert tempTrans transSet)
651 tempStamp = UTCTime { utctDay = fromGregorian 2000 1 1,
742 tempStamp = UTCTime { utctDay = fromGregorian 2000 1 1,
652 utctDayTime = secondsToDiffTime 0 }
743 utctDayTime = secondsToDiffTime 0 }
653 tempSchemas = Schemas context M.empty
744 tempSchemas = Schemas context M.empty
654− tempTrans = Transaction U.nil tempTransInfo tempSchemas
655− tempTransInfo = TransactionInfo { parents = transId NE.:| [],
745+ tempTrans = Transaction U.nil (TransactionInfo (transId NE.:| []) tempStamp) tempSchemas
660 deps = inclusionDependencies context
747 deps = inclusionDependencies context
748+ reEnv = mkRelationalExprEnv context transId graph
661 -- no optimization available here, really? perhaps the optimizer should be passed down to here or the eval function should be passed through the environment
749 -- no optimization available here, really? perhaps the optimizer should be passed down to here or the eval function should be passed through the environment
662 checkIncDep depName (InclusionDependency subsetExpr supersetExpr) = do
750 checkIncDep depName (InclusionDependency subsetExpr supersetExpr) = do
663− let process = runProcessExprM UncommittedContextMarker
664− gfSubsetExpr = process (processRelationalExpr subsetExpr)
751+ let gfSubsetExpr = runReader (processRelationalExpr subsetExpr) reEnv
665− gfSupersetExpr = process (processRelationalExpr supersetExpr)
752+ gfSupersetExpr = runReader (processRelationalExpr supersetExpr) reEnv
666 --if both expressions are of a single-attribute (such as with a simple foreign key), the names of the attributes are irrelevant (they need not match) because the expression is unambiguous, but special-casing this to rename the attribute automatically would not be orthogonal behavior and probably cause confusion. Instead, special case the error to make it clear.
753 --if both expressions are of a single-attribute (such as with a simple foreign key), the names of the attributes are irrelevant (they need not match) because the expression is unambiguous, but special-casing this to rename the attribute automatically would not be orthogonal behavior and probably cause confusion. Instead, special case the error to make it clear.
667− let gfEnv = freshGraphRefRelationalExprEnv (Just context) graph
754+ typeSub <- runReader (typeForRelationalExpr subsetExpr) reEnv
668− runGfRel = runGraphRefRelationalExprM gfEnv
755+ typeSuper <- runReader (typeForRelationalExpr supersetExpr) reEnv
669− typeSub <- runGfRel (typeForGraphRefRelationalExpr gfSubsetExpr)
670− typeSuper <- runGfRel (typeForGraphRefRelationalExpr gfSupersetExpr)
671 when (typeSub /= typeSuper) (Left (RelationTypeMismatchError (attributes typeSub) (attributes typeSuper)))
756 when (typeSub /= typeSuper) (Left (RelationTypeMismatchError (attributes typeSub) (attributes typeSuper)))
672 let checkExpr = Equals gfSupersetExpr (Union gfSubsetExpr gfSupersetExpr)
757 let checkExpr = Equals gfSupersetExpr (Union gfSubsetExpr gfSupersetExpr)
673− gfEvald = runGraphRefRelationalExprM gfEnv' (evalGraphRefRelationalExpr checkExpr)
758+ case evalGraphRefRelationalExpr checkExpr potentialGraph of
674− gfEnv' = freshGraphRefRelationalExprEnv (Just context) potentialGraph
676 Left err -> Left err
759 Left err -> Left err
677 Right resultRel -> if resultRel == relationTrue then
760 Right resultRel -> if resultRel == relationTrue then
@@ -682,81 +765,87 @@ checkConstraints context transId graph@(TransactionGraph graphHeads transSet) =
682-- the type of a relational expression is equal to the relation attribute set returned from executing the relational expression; therefore, the type can be cheaply derived by evaluating a relational expression and ignoring and tuple processing
765-- the type of a relational expression is equal to the relation attribute set returned from executing the relational expression; therefore, the type can be cheaply derived by evaluating a relational expression and ignoring and tuple processing
683-- furthermore, the type of a relational expression is the resultant header of the evaluated empty-tupled relation
766-- furthermore, the type of a relational expression is the resultant header of the evaluated empty-tupled relation
685−typeForRelationalExpr :: RelationalExpr -> RelationalExprM Relation
768+typeForRelationalExpr :: RelationalExpr -> RelationalExprState (Either RelationalError Relation)
686typeForRelationalExpr expr = do
769typeForRelationalExpr expr = do
687 --replace the relationVariables context element with a cloned set of relation devoid of tuples
770 --replace the relationVariables context element with a cloned set of relation devoid of tuples
688 --evalRelationalExpr could still return an existing relation with tuples, so strip them
771 --evalRelationalExpr could still return an existing relation with tuples, so strip them
690− context <- reContext
691− let gfExpr = runProcessExprM UncommittedContextMarker (processRelationalExpr expr)
772+ gfExpr <- processRelationalExpr expr
692− gfEnv = freshGraphRefRelationalExprEnv (Just context) graph
693− runGf = runGraphRefRelationalExprM gfEnv (typeForGraphRefRelationalExpr gfExpr)
773+ typeForGraphRefRelationalExpr gfExpr
694− lift $ except runGf
774+
775+--returns a database context with all tuples removed
776+--this is useful for type checking and optimization
778+contextWithEmptyTupleSets :: DatabaseContext -> DatabaseContext
779+contextWithEmptyTupleSets contextIn = contextIn { relationVariables = relVars }
781+ relVars = M.map (\rel -> ExistingRelation (Relation (attributes rel) emptyTupleSet)) (relationVariables contextIn)
696liftE :: (Monad m) => m (Either a b) -> ExceptT a m b
784liftE :: (Monad m) => m (Either a b) -> ExceptT a m b
697liftE v = do
785liftE v = do
698 y <- lift v
786 y <- lift v
699 case y of
787 case y of
700− Left err -> throwError err
788+ Left err -> throwE err
701 Right val -> pure val
789 Right val -> pure val
703{- used for restrictions- take the restrictionpredicate and return the corresponding filter function -}
791{- used for restrictions- take the restrictionpredicate and return the corresponding filter function -}
704−predicateRestrictionFilter :: Attributes -> GraphRefRestrictionPredicateExpr -> GraphRefRelationalExprM RestrictionFilter
792+predicateRestrictionFilter :: Attributes -> RestrictionPredicateExprBase a -> RelationalExprState (Either RelationalError RestrictionFilter)
705−predicateRestrictionFilter attrs (AndPredicate expr1 expr2) = do
793+predicateRestrictionFilter attrs (AndPredicate expr1 expr2) =
706− expr1v <- predicateRestrictionFilter attrs expr1
795+ expr1v <- liftE (predicateRestrictionFilter attrs expr1)
707− expr2v <- predicateRestrictionFilter attrs expr2
796+ expr2v <- liftE (predicateRestrictionFilter attrs expr2)
708− pure (\x -> do
797+ pure (\x -> do
709− ev1 <- expr1v x
798+ ev1 <- expr1v x
710− ev2 <- expr2v x
799+ ev2 <- expr2v x
711− pure (ev1 && ev2))
800+ pure (ev1 && ev2))
713−predicateRestrictionFilter attrs (OrPredicate expr1 expr2) = do
802+predicateRestrictionFilter attrs (OrPredicate expr1 expr2) =
714− expr1v <- predicateRestrictionFilter attrs expr1
804+ expr1v <- liftE (predicateRestrictionFilter attrs expr1)
715− expr2v <- predicateRestrictionFilter attrs expr2
805+ expr2v <- liftE (predicateRestrictionFilter attrs expr2)
716 pure (\x -> do
806 pure (\x -> do
717 ev1 <- expr1v x
807 ev1 <- expr1v x
718 ev2 <- expr2v x
808 ev2 <- expr2v x
719 pure (ev1 || ev2))
809 pure (ev1 || ev2))
721−predicateRestrictionFilter _ TruePredicate = pure (\_ -> pure True)
811+predicateRestrictionFilter _ TruePredicate = pure (Right (\_ -> pure True))
723−predicateRestrictionFilter attrs (NotPredicate expr) = do
813+predicateRestrictionFilter attrs (NotPredicate expr) =
724− exprv <- predicateRestrictionFilter attrs expr
815+ exprv <- liftE (predicateRestrictionFilter attrs expr)
725− pure (fmap not . exprv)
816+ pure (fmap not . exprv)
727--optimization opportunity: if the subexpression does not reference attributes in the top-level expression, then it need only be evaluated once, statically, outside the tuple filter- see historical implementation here
818--optimization opportunity: if the subexpression does not reference attributes in the top-level expression, then it need only be evaluated once, statically, outside the tuple filter- see historical implementation here
728predicateRestrictionFilter _ (RelationalExprPredicate relExpr) = do
820predicateRestrictionFilter _ (RelationalExprPredicate relExpr) = do
729− renv <- askEnv
821+ rstate <- ask
730− let eval :: RelationTuple -> Either RelationalError Relation
822+ pure (Right (\tup -> case runReader (evalRelationalExpr relExpr) (mergeTuplesIntoRelationalExprState tup rstate) of
732− let gfEnv = mergeTuplesIntoGraphRefRelationalExprEnv tup renv in
733− runGraphRefRelationalExprM gfEnv (evalGraphRefRelationalExpr relExpr)
734− pure (\tup -> case eval tup of
735 Left err -> Left err
823 Left err -> Left err
736 Right rel -> if arity rel /= 0 then
824 Right rel -> if arity rel /= 0 then
737 Left (PredicateExpressionError "Relational restriction filter must evaluate to 'true' or 'false'")
825 Left (PredicateExpressionError "Relational restriction filter must evaluate to 'true' or 'false'")
739− pure (rel == relationTrue))
827+ pure (rel == relationTrue)))
741predicateRestrictionFilter attrs (AttributeEqualityPredicate attrName atomExpr) = do
829predicateRestrictionFilter attrs (AttributeEqualityPredicate attrName atomExpr) = do
742− env <- askEnv
830+ rstate <- ask
743− let attrs' = A.union attrs (envAttributes env)
831+ let attrs' = stateAttributes rstate
744− ctxtup' = envTuple env
832+ ctxtup' = stateTuple rstate
745− atomExprType <- typeForGraphRefAtomExpr attrs' atomExpr
834+ atomExprType <- liftE (typeFromAtomExpr attrs' atomExpr)
746− attr <- lift $ except $ case A.attributeForName attrName attrs of
835+ attr <- either throwE pure $ case A.attributeForName attrName attrs of
747 Right attr -> Right attr
836 Right attr -> Right attr
748 Left (NoSuchAttributeNamesError _) -> case A.attributeForName attrName (tupleAttributes ctxtup') of
837 Left (NoSuchAttributeNamesError _) -> case A.attributeForName attrName (tupleAttributes ctxtup') of
749 Right ctxattr -> Right ctxattr
838 Right ctxattr -> Right ctxattr
750 Left err2@(NoSuchAttributeNamesError _) -> Left err2
839 Left err2@(NoSuchAttributeNamesError _) -> Left err2
751 Left err -> Left err
840 Left err -> Left err
752 Left err -> Left err
841 Left err -> Left err
753− if atomExprType /= A.atomType attr then
842+ if atomExprType /= A.atomType attr then
754− throwError (TupleAttributeTypeMismatchError (A.attributesFromList [attr]))
843+ throwE (TupleAttributeTypeMismatchError (A.attributesFromList [attr]))
756 pure $ \tupleIn -> let evalAndCmp atomIn = case atomEvald of
845 pure $ \tupleIn -> let evalAndCmp atomIn = case atomEvald of
757 Right atomCmp -> atomCmp == atomIn
846 Right atomCmp -> atomCmp == atomIn
758 Left _ -> False
847 Left _ -> False
759− atomEvald = runGraphRefRelationalExprM env (evalGraphRefAtomExpr tupleIn atomExpr)
848+ atomEvald = runReader (evalAtomExpr tupleIn atomExpr) rstate
761 pure $ case atomForAttributeName attrName tupleIn of
850 pure $ case atomForAttributeName attrName tupleIn of
762 Left (NoSuchAttributeNamesError _) -> case atomForAttributeName attrName ctxtup' of
851 Left (NoSuchAttributeNamesError _) -> case atomForAttributeName attrName ctxtup' of
@@ -767,322 +856,277 @@ predicateRestrictionFilter attrs (AttributeEqualityPredicate attrName atomExpr)
767-- in the future, it would be useful to do typechecking on the attribute and atom expr filters in advance
856-- in the future, it would be useful to do typechecking on the attribute and atom expr filters in advance
768predicateRestrictionFilter attrs (AtomExprPredicate atomExpr) = do
857predicateRestrictionFilter attrs (AtomExprPredicate atomExpr) = do
769 --merge attrs into the state attributes
858 --merge attrs into the state attributes
770− renv <- askEnv
859+ rstate <- ask
771− aType <- typeForGraphRefAtomExpr attrs atomExpr
861+ aType <- liftE (typeFromAtomExpr attrs atomExpr)
772− if aType /= BoolAtomType then
862+ if aType /= BoolAtomType then
773− throwError (AtomTypeMismatchError aType BoolAtomType)
863+ throwE (AtomTypeMismatchError aType BoolAtomType)
775 pure (\tupleIn ->
865 pure (\tupleIn ->
776− case runGraphRefRelationalExprM renv (evalGraphRefAtomExpr tupleIn atomExpr) of
866+ case runReader (evalAtomExpr tupleIn atomExpr) rstate of
777− Left err -> Left err
867+ Left err -> Left err
778− Right boolAtomValue -> pure (boolAtomValue == BoolAtom True))
868+ Right boolAtomValue -> pure (boolAtomValue == BoolAtom True))
780tupleExprCheckNewAttrName :: AttributeName -> Relation -> Either RelationalError Relation
870tupleExprCheckNewAttrName :: AttributeName -> Relation -> Either RelationalError Relation
781tupleExprCheckNewAttrName attrName rel = if isRight (attributeForName attrName rel) then
871tupleExprCheckNewAttrName attrName rel = if isRight (attributeForName attrName rel) then
782 Left (AttributeNameInUseError attrName)
872 Left (AttributeNameInUseError attrName)
784 Right rel
874 Right rel
786−extendGraphRefTupleExpressionProcessor :: Relation -> GraphRefExtendTupleExpr -> GraphRefRelationalExprM (Attributes, RelationTuple -> Either RelationalError RelationTuple)
876+extendTupleExpressionProcessor :: Relation -> ExtendTupleExpr -> RelationalExprState (Either RelationalError (Attributes, RelationTuple -> Either RelationalError RelationTuple))
787−extendGraphRefTupleExpressionProcessor relIn (AttributeExtendTupleExpr newAttrName atomExpr) =
877+extendTupleExpressionProcessor relIn (AttributeExtendTupleExpr newAttrName atomExpr) = do
788−-- renv <- askEnv
878+ rstate <- askEnv
789 -- check that the attribute name is not in use
879 -- check that the attribute name is not in use
790 case tupleExprCheckNewAttrName newAttrName relIn of
880 case tupleExprCheckNewAttrName newAttrName relIn of
791− Left err -> throwError err
881+ Left err -> pure (Left err)
792− Right _ -> do
882+ Right _ -> runExceptT $ do
793− atomExprType <- typeForGraphRefAtomExpr (attributes relIn) atomExpr
883+ atomExprType <- liftE (typeFromAtomExpr (attributes relIn) atomExpr)
794− atomExprType' <- verifyGraphRefAtomExprTypes relIn atomExpr atomExprType
884+ atomExprType' <- liftE (verifyAtomExprTypes relIn atomExpr atomExprType)
795 let newAttrs = A.attributesFromList [Attribute newAttrName atomExprType']
885 let newAttrs = A.attributesFromList [Attribute newAttrName atomExprType']
796 newAndOldAttrs = A.addAttributes (attributes relIn) newAttrs
886 newAndOldAttrs = A.addAttributes (attributes relIn) newAttrs
798− pure (newAndOldAttrs, \tup -> do
887+ pure (newAndOldAttrs, \tup -> let substate = mergeTuplesIntoRelationalExprState tup rstate in
799− let gfEnv = mergeTuplesIntoGraphRefRelationalExprEnv tup env
888+ case unimplemented {-runReader (evalAtomExpr tup atomExpr) substate-} of
800− atom <- runGraphRefRelationalExprM gfEnv (evalGraphRefAtomExpr tup atomExpr)
889+ Left err -> Left err
801− Right (tupleAtomExtend newAttrName atom tup)
890+ Right atom -> Right (tupleAtomExtend newAttrName atom tup)
804−evalGraphRefAtomExpr :: RelationTuple -> GraphRefAtomExpr -> GraphRefRelationalExprM Atom
893+
805−evalGraphRefAtomExpr tupIn (AttributeAtomExpr attrName) =
894+evalAtomExpr :: RelationTuple -> AtomExpr -> RelationalExprState (Either RelationalError Atom)
895+evalAtomExpr = undefined
806− case atomForAttributeName attrName tupIn of
898+evalAtomExpr tupIn (AttributeAtomExpr attrName) = case atomForAttributeName attrName tupIn of
807− Right atom -> pure atom
899+ Right atom -> pure (Right atom)
808− Left err@(NoSuchAttributeNamesError _) -> do
900+ err@(Left (NoSuchAttributeNamesError _)) -> do
809− env <- askEnv
901+ rstate <- ask
810− case gre_extra env of
902+ let stateTup = stateTuple rstate
811− Nothing -> throwError err
812− Just (Left ctxtup) -> lift $ except $ atomForAttributeName attrName ctxtup
903+ pure (atomForAttributeName attrName stateTup)
813− Just (Right _) -> throwError err
814− Left err -> throwError err
904+ Left err -> pure (Left err)
815−evalGraphRefAtomExpr _ (NakedAtomExpr atom) = pure atom
905+evalAtomExpr _ (NakedAtomExpr atom) = pure (Right atom)
816−evalGraphRefAtomExpr tupIn (FunctionAtomExpr funcName arguments tid) = do
906+evalAtomExpr tupIn (FunctionAtomExpr funcName arguments ()) = do
817− argTypes <- mapM (typeForGraphRefAtomExpr (tupleAttributes tupIn)) arguments
907+ argTypes <- mapM (typeFromAtomExpr (tupleAttributes tupIn)) arguments
818− context <- gfDatabaseContextForMarker tid
908+ context <- fmap stateElemsContext ask
819− let functions = atomFunctions context
910+ let functions = atomFunctions context
820− func <- lift $ except (atomFunctionForName funcName functions)
911+ func <- either throwE pure (atomFunctionForName funcName functions)
821− let expectedArgCount = length (atomFuncType func) - 1
912+ let expectedArgCount = length (atomFuncType func) - 1
822− actualArgCount = length argTypes
913+ actualArgCount = length argTypes
823− safeInit [] = [] -- different behavior from normal init
914+ safeInit [] = [] -- different behavior from normal init
824− safeInit xs = init xs
915+ safeInit xs = init xs
825− if expectedArgCount /= actualArgCount then
916+ if expectedArgCount /= actualArgCount then
826− throwError (FunctionArgumentCountMismatchError expectedArgCount actualArgCount)
917+ throwE (FunctionArgumentCountMismatchError expectedArgCount actualArgCount)
828 let zippedArgs = zip (safeInit (atomFuncType func)) argTypes
919 let zippedArgs = zip (safeInit (atomFuncType func)) argTypes
829− mapM_ (\(expType, actType) ->
920+ mapM_ (\(expType, eActType) -> do
921+ actType <- either throwE pure eActType
830− lift $ except (atomTypeVerify expType actType)) zippedArgs
922+ either throwE pure (atomTypeVerify expType actType)) zippedArgs
831− evaldArgs <- mapM (evalGraphRefAtomExpr tupIn) arguments
923+ evaldArgs <- mapM (liftE . evalAtomExpr tupIn) arguments
832 case evalAtomFunction func evaldArgs of
924 case evalAtomFunction func evaldArgs of
833− Left err -> throwError (AtomFunctionUserError err)
925+ Left err -> throwE (AtomFunctionUserError err)
834 Right result -> do
926 Right result -> do
835 --validate that the result matches the expected type
927 --validate that the result matches the expected type
836− _ <- lift $ except (atomTypeVerify (last (atomFuncType func)) (atomTypeForAtom result))
928+ _ <- either throwE pure (atomTypeVerify (last (atomFuncType func)) (atomTypeForAtom result))
837 pure result
929 pure result
838−evalGraphRefAtomExpr tupIn (RelationAtomExpr relExpr) = do
930+evalAtomExpr tupIn (RelationAtomExpr relExpr) = do
839 --merge existing state tuple context into new state tuple context to support an arbitrary number of levels, but new attributes trounce old attributes
931 --merge existing state tuple context into new state tuple context to support an arbitrary number of levels, but new attributes trounce old attributes
840− env <- ask
932+ rstate <- ask
841− let gfEnv = mergeTuplesIntoGraphRefRelationalExprEnv tupIn env
933+ runExceptT $ do
842− relAtom <- lift $ except $ runGraphRefRelationalExprM gfEnv (evalGraphRefRelationalExpr relExpr)
934+ let newState = mergeTuplesIntoRelationalExprState tupIn rstate
935+ relAtom <- either throwE pure (runReader (evalRelationalExpr relExpr) newState)
843− pure (RelationAtom relAtom)
936+ pure (RelationAtom relAtom)
844−evalGraphRefAtomExpr tupIn cons@(ConstructedAtomExpr dConsName dConsArgs _) = do --why is the tid unused here? suspicious
937+evalAtomExpr tupIn cons@(ConstructedAtomExpr dConsName dConsArgs ()) = runExceptT $ do
845− let mergeEnv = mergeTuplesIntoGraphRefRelationalExprEnv tupIn
938+ rstate <- lift ask
939+ let newState = mergeTuplesIntoRelationalExprState tupIn rstate
846− aType <- local mergeEnv (typeForGraphRefAtomExpr (tupleAttributes tupIn) cons)
940+ aType <- either throwE pure (runReader (typeFromAtomExpr (tupleAttributes tupIn) cons) newState)
847− argAtoms <- local mergeEnv $
941+ argAtoms <- mapM (\arg -> either throwE pure (runReader (evalAtomExpr tupIn arg) newState)) dConsArgs
848− mapM (evalGraphRefAtomExpr tupIn) dConsArgs
849 pure (ConstructedAtom dConsName aType argAtoms)
942 pure (ConstructedAtom dConsName aType argAtoms)
851−typeForGraphRefAtomExpr :: Attributes -> GraphRefAtomExpr -> GraphRefRelationalExprM AtomType
944+typeForGraphRefAtomExpr :: Attributes -> GraphRefAtomExpr -> RelationalExprState (Either RelationalError AtomType)
852typeForGraphRefAtomExpr attrs (AttributeAtomExpr attrName) = do
945typeForGraphRefAtomExpr attrs (AttributeAtomExpr attrName) = do
853− renv <- askEnv
946+ rstate <- askEnv
854 case A.atomTypeForAttributeName attrName attrs of
947 case A.atomTypeForAttributeName attrName attrs of
855− Right aType -> pure aType
948+ Right aType -> pure (Right aType)
856 Left err@(NoSuchAttributeNamesError _) ->
949 Left err@(NoSuchAttributeNamesError _) ->
857− let envTup = envTuple renv
950+ let stateTup = stateTuple rstate
858− envAttrs = envAttributes renv in
951+ stateAttrs = stateAttributes rstate in
859− case A.attributeForName attrName envAttrs of
952+ case A.attributeForName attrName stateAttrs of
860− Right attr -> pure (A.atomType attr)
953+ Right attr -> pure (Right (A.atomType attr))
861− Left _ -> case atomForAttributeName attrName envTup of
954+ Left _ -> case atomForAttributeName attrName stateTup of
862− Right atom -> pure (atomTypeForAtom atom)
955+ Right atom -> pure (Right (atomTypeForAtom atom))
863− Left _ -> --throwError (traceStack (show ("typeForGRAtomExpr", attrs, envTup)) err)
956+ Left _ -> pure (Left err)
865− Left err -> throwError err
867−typeForGraphRefAtomExpr _ (NakedAtomExpr atom) = pure (atomTypeForAtom atom)
958+typeForGraphAtomExpr _ (NakedAtomExpr atom) = pure (Right (atomTypeForAtom atom))
868−typeForGraphRefAtomExpr attrs (FunctionAtomExpr funcName atomArgs transId) = do
959+typeForGraphAtomExpr attrs (FunctionAtomExpr funcName atomArgs _) = do
869− funcs <- atomFunctions <$> gfDatabaseContextForMarker transId
960+ context <- fmap envContext askEnv
961+ let funcs = atomFunctions context
870 case atomFunctionForName funcName funcs of
962 case atomFunctionForName funcName funcs of
871− Left err -> throwError err
963+ Left err -> pure (Left err)
872 Right func -> do
964 Right func -> do
873 let funcRetType = last (atomFuncType func)
965 let funcRetType = last (atomFuncType func)
874 funcArgTypes = init (atomFuncType func)
966 funcArgTypes = init (atomFuncType func)
875− argTypes <- mapM (typeForGraphRefAtomExpr attrs) atomArgs
967+ eArgTypes <- mapM (typeFromAtomExpr attrs) atomArgs
968+ case lefts eArgTypes of
969+ errs@(_:_) -> pure (Left (someErrors errs))
876− let eTvMap = resolveTypeVariables funcArgTypes argTypes
971+ let eTvMap = resolveTypeVariables funcArgTypes argTypes
972+ argTypes = rights eArgTypes
877− case eTvMap of
973+ case eTvMap of
878− Left err -> throwError err
974+ Left err -> pure (Left err)
879− Right tvMap -> lift $ except $ resolveFunctionReturnValue funcName tvMap funcRetType
975+ Right tvMap -> pure (resolveFunctionReturnValue funcName tvMap funcRetType)
880−typeForGraphRefAtomExpr attrs (RelationAtomExpr relExpr) = do
976+typeFromAtomExpr attrs (RelationAtomExpr relExpr) = do
881− relType <- R.local (mergeAttributesIntoGraphRefRelationalExprEnv attrs) (typeForGraphRefRelationalExpr relExpr)
977+ relType <- R.local (mergeAttributesIntoRelationalExprState attrs) (typeForRelationalExpr relExpr)
979+ Left err -> pure (Left err)
882− pure (RelationAtomType (attributes relType))
981+ pure (pure (RelationAtomType (attributes relType')))
883-- grab the type of the data constructor, then validate that the args match the expected types
982-- grab the type of the data constructor, then validate that the args match the expected types
884−typeForGraphRefAtomExpr attrs (ConstructedAtomExpr dConsName dConsArgs tid) =
983+typeFromAtomExpr attrs (ConstructedAtomExpr dConsName dConsArgs _) =
885− do
984+ runExceptT $ do
886− argsTypes <- mapM (typeForGraphRefAtomExpr attrs) dConsArgs
985+ argsTypes <- mapM (liftE . typeFromAtomExpr attrs) dConsArgs
887− tConsMap <- typeConstructorMapping <$> gfDatabaseContextForMarker tid
986+ context <- fmap envContext (lift askEnv)
888− lift $ except $ atomTypeForDataConstructor tConsMap dConsName argsTypes
987+ either throwE pure (atomTypeForDataConstructor (typeConstructorMapping context) dConsName argsTypes)
890-- | Validate that the type of the AtomExpr matches the expected type.
989-- | Validate that the type of the AtomExpr matches the expected type.
891−verifyGraphRefAtomExprTypes :: Relation -> GraphRefAtomExpr -> AtomType -> GraphRefRelationalExprM AtomType
990+verifyAtomExprTypes :: Relation -> AtomExpr -> AtomType -> RelationalExprState (Either RelationalError AtomType)
892−verifyGraphRefAtomExprTypes relIn (AttributeAtomExpr attrName) expectedType = do
991+verifyAtomExprTypes relIn (AttributeAtomExpr attrName) expectedType = runExceptT $ do
893− env <- askEnv
992+ rstate <- lift askEnv
894 case A.atomTypeForAttributeName attrName (attributes relIn) of
993 case A.atomTypeForAttributeName attrName (attributes relIn) of
895− Right aType -> lift $ except $ atomTypeVerify expectedType aType
994+ Right aType -> either throwE pure (atomTypeVerify expectedType aType)
896 (Left err@(NoSuchAttributeNamesError _)) ->
995 (Left err@(NoSuchAttributeNamesError _)) ->
897− let attrs' = envAttributes env in
996+ let attrs' = stateAttributes rstate in
898 if attrs' == emptyAttributes then
997 if attrs' == emptyAttributes then
899− throwError err
998+ throwE err
901 case A.attributeForName attrName attrs' of
1000 case A.attributeForName attrName attrs' of
902− Left err' -> throwError err'
1001+ Left err' -> throwE err'
903− Right attrType -> lift $ except $ atomTypeVerify expectedType (A.atomType attrType)
1002+ Right attrType -> either throwE pure (atomTypeVerify expectedType (A.atomType attrType))
904− Left err -> throwError err
906−verifyGraphRefAtomExprTypes _ (NakedAtomExpr atom) expectedType =
907− lift $ except $ atomTypeVerify expectedType (atomTypeForAtom atom)
1003+verifyAtomExprTypes _ (NakedAtomExpr atom) expectedType = pure (atomTypeVerify expectedType (atomTypeForAtom atom))
908−verifyGraphRefAtomExprTypes relIn (FunctionAtomExpr funcName funcArgExprs tid) expectedType = do
1004+verifyAtomExprTypes relIn (FunctionAtomExpr funcName funcArgExprs _) expectedType = do
909− context <- gfDatabaseContextForMarker tid
1005+ rstate <- askEnv
910 let functions = atomFunctions context
1006 let functions = atomFunctions context
911− func <- lift $ except $ atomFunctionForName funcName functions
1007+ context = envContext rstate
912− let expectedArgTypes = atomFuncType func
1008+ runExceptT $ do
913− funcArgVerifier (atomExpr, expectedType2, argCount) = do
1009+ func <- either throwE pure (atomFunctionForName funcName functions)
914− let handler :: RelationalError -> GraphRefRelationalExprM AtomType
1010+ let expectedArgTypes = atomFuncType func
915− handler (AtomTypeMismatchError expSubType actSubType) = throwError (AtomFunctionTypeError funcName argCount expSubType actSubType)
1011+ funcArgTypes <- mapM (\(atomExpr,expectedType2,argCount) -> case runReader (verifyAtomExprTypes relIn atomExpr expectedType2) rstate of
916− handler err = throwError err
1012+ Left (AtomTypeMismatchError expSubType actSubType) -> throwE (AtomFunctionTypeError funcName argCount expSubType actSubType)
917− verifyGraphRefAtomExprTypes relIn atomExpr expectedType2 `catchError` handler
1013+ Left err -> throwE err
918− funcArgTypes <- mapM funcArgVerifier $ zip3 funcArgExprs expectedArgTypes [1..]
1014+ Right x -> pure x
919− if length funcArgTypes /= length expectedArgTypes - 1 then
1015+ ) $ zip3 funcArgExprs expectedArgTypes [1..]
920− throwError (AtomTypeCountError funcArgTypes expectedArgTypes)
1016+ if length funcArgTypes /= length expectedArgTypes - 1 then
1017+ throwE (AtomTypeCountError funcArgTypes expectedArgTypes)
922− lift $ except $ atomTypeVerify expectedType (last expectedArgTypes)
1019+ either throwE pure (atomTypeVerify expectedType (last expectedArgTypes))
923−verifyGraphRefAtomExprTypes relIn (RelationAtomExpr relationExpr) expectedType =
1020+verifyAtomExprTypes relIn (RelationAtomExpr relationExpr) expectedType = runExceptT $ do
924− do
1021+ rstate <- lift askEnv
925− let mergedAttrsEnv e = mergeAttributesIntoGraphRefRelationalExprEnv (attributes relIn) e
1022+ relType <- either throwE pure (runReader (typeForRelationalExpr relationExpr) (mergeAttributesIntoRelationalExprState (attributes relIn) rstate))
926− relType <- R.local mergedAttrsEnv (typeForGraphRefRelationalExpr relationExpr)
1023+ either throwE pure (atomTypeVerify expectedType (RelationAtomType (attributes relType)))
927− lift $ except $ atomTypeVerify expectedType (RelationAtomType (attributes relType))
1024+verifyAtomExprTypes rel cons@ConstructedAtomExpr{} expectedType = runExceptT $ do
928−verifyGraphRefAtomExprTypes rel cons@ConstructedAtomExpr{} expectedType = do
1025+ cType <- liftE (typeFromAtomExpr (attributes rel) cons)
929− cType <- typeForGraphRefAtomExpr (attributes rel) cons
1026+ either throwE pure (atomTypeVerify expectedType cType)
930− lift $ except $ atomTypeVerify expectedType cType
932-- | Look up the type's name and create a new attribute.
1028-- | Look up the type's name and create a new attribute.
933−evalGraphRefAttrExpr :: GraphRefAttributeExpr -> GraphRefRelationalExprM Attribute
1029+evalGraphRefAttrExpr :: GraphRefAttributeExpr -> RelationalExprState (Either RelationalError Attribute)
934evalGraphRefAttrExpr (AttributeAndTypeNameExpr attrName tCons transId) = do
1030evalGraphRefAttrExpr (AttributeAndTypeNameExpr attrName tCons transId) = do
935− tConsMap <- typeConstructorMapping <$> gfDatabaseContextForMarker transId
1031+ graph <- re_graph <$> askEnv
936− aType <- lift $ except $ atomTypeForTypeConstructorValidate True tCons tConsMap M.empty
1032+ case transactionForId transId graph of
937− lift $ except $ validateAtomType aType tConsMap
1033+ Left err -> pure (Left err)
938− pure $ Attribute attrName aType
1034+ Right trans -> do
1035+ let tConsMap = typeConstructorMapping (concreteDatabaseContext trans)
1037+ aType <- atomTypeForTypeConstructorValidate True tCons tConsMap M.empty
1038+ validateAtomType aType tConsMap
1041+ Left err -> pure (Left err)
1043+ pure $ Right (Attribute attrName aType)
1045+evalGraphRefAttrExpr (NakedAttributeExpr attr) = pure $ Right attr
940−evalGraphRefAttrExpr (NakedAttributeExpr attr) = pure attr
1047+evalTupleExpr :: Maybe Attributes -> TupleExpr -> RelationalExprState (Either RelationalError RelationTuple)
941−
1048+evalTupleExpr mAttrs (TupleExpr tupMap) = do
942−-- for tuple type concrete resolution (Nothing ==> Maybe Int) when the attributes hint is Nothing, we need to first process all the tuples, then extract the concrete types on a per-attribute basis, then reprocess the tuples to include the concrete types
1049+ context <- fmap envContext askEnv
943−evalGraphRefTupleExprs :: Maybe Attributes -> GraphRefTupleExprs -> GraphRefRelationalExprM [RelationTuple]
1050+ runExceptT $ do
944−evalGraphRefTupleExprs _ (TupleExprs _ []) = pure []
945−evalGraphRefTupleExprs mAttrs (TupleExprs fixedMarker tupleExprL) = do
946− tuples <- mapM (evalGraphRefTupleExpr mAttrs) tupleExprL
947− finalAttrs <- case mAttrs of
948− Just attrs -> pure attrs
951− [] -> pure emptyAttributes
952− (headTuple:tailTuples) -> do
953− --gather up resolved atom types or throw an error if an attribute cannot be made concrete from the inferred types- this could still fail if the type cannot be inferred (e.g. from [Nothing, Nothing])
955− processTupleAttrs (tupAttr, accAttr) =
956− --if the attribute is a constructedatomtype, we can recurse into it to potentially resolve type variables
957− if isResolvedAttribute accAttr && tupAttr == accAttr then
960− lift $ except $ resolveAttributes accAttr tupAttr
961− mostResolvedTypes <-
962− foldM (\acc tup -> do
963− let zipped = zip (V.toList . attributesVec $ tupleAttributes tup) acc
964− accNames = S.fromList $ map A.attributeName acc
965− tupNames = A.attributeNameSet (tupleAttributes tup)
966− attrNamesDiff = S.union (S.difference accNames tupNames) (S.difference tupNames accNames)
967− unless (null attrNamesDiff) (throwError (AttributeNamesMismatchError attrNamesDiff))
968− nextTupleAttrs <- mapM processTupleAttrs zipped
969− let diff = A.attributesDifference (A.attributesFromList nextTupleAttrs) (A.attributesFromList acc)
970− if diff == A.emptyAttributes then
973− throwError (TupleAttributeTypeMismatchError diff)
974− ) (V.toList . attributesVec $ tupleAttributes headTuple) tailTuples
975− pure (A.attributesFromList mostResolvedTypes)
976− --strategy: if all the tuple expr transaction markers refer to one location, then we can pass the type constructor mapping from that location, otherwise, we cannot assume that the types are the same
977− tConsMap <- case singularTransactions tupleExprL of
978− SingularTransactionRef commonTransId ->
979− typeConstructorMapping <$> gfDatabaseContextForMarker commonTransId
980− NoTransactionsRef ->
981− typeConstructorMapping <$> gfDatabaseContextForMarker fixedMarker
982− -- if there are multiple transaction markers in the TupleExprs, then we can't assume a single type constructor mapping- this could be improved in the future, but if all the tuples are fully resolved, then we don't need further resolution
983− _ -> throwError TupleExprsReferenceMultipleMarkersError
984− lift $ except $ validateAttributes tConsMap finalAttrs
985− mapM (lift . except . resolveTypesInTuple finalAttrs tConsMap) tuples
988−--resolveAttributes (Attribute "gonk" (ConstructedAtomType "Either" (fromList [("a",IntegerAtomType),("b",TypeVariableType "b")]))) (Attribute "gonk" (ConstructedAtomType "Either" (fromList [("a",TypeVariableType "a"),("b",TextAtomType)])))
990−evalGraphRefTupleExpr :: Maybe Attributes -> GraphRefTupleExpr -> GraphRefRelationalExprM RelationTuple
991−evalGraphRefTupleExpr mAttrs (TupleExpr tupMap) = do
992 -- it's not possible for AtomExprs in tuple constructors to reference other Attributes' atoms due to the necessary order-of-operations (need a tuple to pass to evalAtomExpr)- it may be possible with some refactoring of type usage or delayed evaluation- needs more thought, but not a priority
1051 -- it's not possible for AtomExprs in tuple constructors to reference other Attributes' atoms due to the necessary order-of-operations (need a tuple to pass to evalAtomExpr)- it may be possible with some refactoring of type usage or delayed evaluation- needs more thought, but not a priority
993 -- I could adjust this logic so that when the attributes are not specified (Nothing), then I can attempt to extract the attributes from the tuple- the type resolution will blow up if an ambiguous data constructor is used (Left 4) and this should allow simple cases to "relation{tuple{a 4}}" to be processed
1052 -- I could adjust this logic so that when the attributes are not specified (Nothing), then I can attempt to extract the attributes from the tuple- the type resolution will blow up if an ambiguous data constructor is used (Left 4) and this should allow simple cases to "relation{tuple{a 4}}" to be processed
994− let attrs = fromMaybe A.emptyAttributes mAttrs
1053+ let attrs = fromMaybe A.emptyAttributes mAttrs
995− resolveOneAtom (attrName, aExpr) =
1054+ attrAtoms <- mapM (\(attrName, aExpr) -> do
996− do
1055+ --provided when the relation header is available
997− --provided when the relation header is available
1056+ let eExpectedAtomType = A.atomTypeForAttributeName attrName attrs
998− let eExpectedAtomType = A.atomTypeForAttributeName attrName attrs
1057+ unresolvedType <- liftE (typeFromAtomExpr attrs aExpr)
999− unresolvedType <- typeForGraphRefAtomExpr attrs aExpr
1058+ resolvedType <- case eExpectedAtomType of
1000− resolvedType <- case eExpectedAtomType of
1001 Left _ -> pure unresolvedType
1059 Left _ -> pure unresolvedType
1002− Right typeHint -> lift $ except $ resolveAtomType typeHint unresolvedType
1060+ Right typeHint -> either throwE pure (resolveAtomType typeHint unresolvedType)
1003 --resolve atom typevars based on resolvedType?
1061 --resolve atom typevars based on resolvedType?
1004− newAtom <- evalGraphRefAtomExpr emptyTuple aExpr
1062+ newAtom <- liftE (evalAtomExpr emptyTuple aExpr)
1005− pure (attrName, newAtom, resolvedType)
1063+ pure (attrName, newAtom, resolvedType)
1006− attrAtoms <- mapM resolveOneAtom (M.toList tupMap)
1064+ ) (M.toList tupMap)
1007− let tupAttrs = A.attributesFromList $ map (\(attrName, _, aType) -> Attribute attrName aType) attrAtoms
1065+ let tupAttrs = A.attributesFromList $ map (\(attrName, _, aType) -> Attribute attrName aType) attrAtoms
1008− atoms = V.fromList $ map (\(_, atom, _) -> atom) attrAtoms
1066+ atoms = V.fromList $ map (\(_, atom, _) -> atom) attrAtoms
1009− tup = mkRelationTuple tupAttrs atoms
1067+ tup = mkRelationTuple tupAttrs atoms
1010− finalAttrs = fromMaybe tupAttrs mAttrs
1068+ tConss = typeConstructorMapping context
1069+ finalAttrs = fromMaybe tupAttrs mAttrs
1011 --verify that the attributes match
1070 --verify that the attributes match
1012− when (A.attributeNameSet finalAttrs /= A.attributeNameSet tupAttrs) $ throwError (TupleAttributeTypeMismatchError tupAttrs)
1071+ when (A.attributeNameSet finalAttrs /= A.attributeNameSet tupAttrs) $ throwE (TupleAttributeTypeMismatchError tupAttrs)
1013− --we can't resolve types here- they have to be resolved at the atom level where the graph ref is held
1072+ tup' <- either throwE pure (resolveTypesInTuple finalAttrs tConss (reorderTuple finalAttrs tup))
1014− --tup' <- lift $ except (resolveTypesInTuple finalAttrs tConss (reorderTuple finalAttrs tup))
1073+ _ <- either throwE pure (validateTuple tup' tConss)
1015− let tup' = reorderTuple finalAttrs tup
1074+ pure tup'
1016− --TODO: restore type resolution
1075+
1017−-- _ <- lift $ except (validateTuple tup' tConss)
1076+evalAttributeNames :: AttributeNames -> RelationalExpr -> RelationalExprState (Either RelationalError (S.Set AttributeName))
1018− pure tup'
1077+evalAttributeNames attrNames expr = do
1019−
1078+ eExprType <- typeForRelationalExpr expr
1020−--temporary implementation until we have a proper planner+executor
1079+ case eExprType of
1021−evalGraphRefRelationalExpr :: GraphRefRelationalExpr -> GraphRefRelationalExprM Relation
1080+ Left err -> pure (Left err)
1022−evalGraphRefRelationalExpr (MakeRelationFromExprs mAttrExprs tupleExprs) = do
1081+ Right exprTyp -> do
1023− mAttrs <- case mAttrExprs of
1082+ let typeNameSet = S.fromList (V.toList (A.attributeNames (attributes exprTyp)))
1024− Just _ ->
1083+ case attrNames of
1025− Just . A.attributesFromList <$> mapM evalGraphRefAttrExpr (fromMaybe [] mAttrExprs)
1084+ AttributeNames names ->
1026− Nothing -> pure Nothing
1085+ case A.projectionAttributesForNames names (attributes exprTyp) of
1027− tuples <- evalGraphRefTupleExprs mAttrs tupleExprs
1086+ Left err -> pure (Left err)
1028− let attrs = fromMaybe firstTupleAttrs mAttrs
1087+ Right attrs -> pure (Right (S.fromList (V.toList (A.attributeNames attrs))))
1029− firstTupleAttrs = if null tuples then A.emptyAttributes else tupleAttributes (head tuples)
1088+
1030− lift $ except $ mkRelation attrs (RelationTupleSet tuples)
1089+ InvertedAttributeNames names -> do
1031−evalGraphRefRelationalExpr (MakeStaticRelation attributeSet tupleSet) =
1090+ let nonExistentAttributeNames = A.attributeNamesNotContained names typeNameSet
1032− lift $ except $ mkRelation attributeSet tupleSet
1091+ if not (S.null nonExistentAttributeNames) then
1033−evalGraphRefRelationalExpr (ExistingRelation rel) = pure rel
1092+ pure (Left (AttributeNamesMismatchError nonExistentAttributeNames))
1034−evalGraphRefRelationalExpr (RelationVariable name tid) = do
1093+ else
1035− ctx <- gfDatabaseContextForMarker tid
1094+ pure (Right (A.nonMatchingAttributeNameSet names typeNameSet))
1096+ UnionAttributeNames namesA namesB -> do
1097+ eNameSetA <- evalAttributeNames namesA expr
1099+ Left err -> pure (Left err)
1100+ Right nameSetA -> do
1101+ eNameSetB <- evalAttributeNames namesB expr
1103+ Left err -> pure (Left err)
1105+ pure (Right (S.union nameSetA nameSetB))
1107+ IntersectAttributeNames namesA namesB -> do
1108+ eNameSetA <- evalAttributeNames namesA expr
1110+ Left err -> pure (Left err)
1111+ Right nameSetA -> do
1112+ eNameSetB <- evalAttributeNames namesB expr
1114+ Left err -> pure (Left err)
1116+ pure (Right (S.intersection nameSetA nameSetB))
1118+ RelationalExprAttributeNames attrExpr -> do
1119+ eAttrExprType <- typeForRelationalExpr attrExpr
1120+ case eAttrExprType of
1121+ Left err -> pure (Left err)
1122+ Right attrExprType -> pure (Right (A.attributeNameSet (attributes attrExprType)))
1124+evalGraphRefRelationalExpr :: GraphRefRelationalExpr -> TransactionGraph -> Either RelationalError Relation
1125+evalGraphRefRelationalExpr (RelationVariable name tid) graph = do
1126+ ctx <- dbContextForTransId tid graph
1036 case M.lookup name (relationVariables ctx) of
1127 case M.lookup name (relationVariables ctx) of
1037− Nothing -> throwError (RelVarNotDefinedError name)
1128+ Nothing -> Left (RelVarNotDefinedError name)
1038− Just rv -> evalGraphRefRelationalExpr rv
1129+ Just rv -> evalGraphRefRelationalExpr rv graph
1039−evalGraphRefRelationalExpr (Project attrNames expr) = do
1040− attrNameSet <- evalGraphRefAttributeNames attrNames expr
1041− rel <- evalGraphRefRelationalExpr expr
1042− lift $ except $ project attrNameSet rel
1043−evalGraphRefRelationalExpr (Union exprA exprB) = do
1044− relA <- evalGraphRefRelationalExpr exprA
1045− relB <- evalGraphRefRelationalExpr exprB
1046− lift $ except $ union relA relB
1047−evalGraphRefRelationalExpr (Join exprA exprB) = do
1048− relA <- evalGraphRefRelationalExpr exprA
1049− relB <- evalGraphRefRelationalExpr exprB
1050− lift $ except $ join relA relB
1051−evalGraphRefRelationalExpr (Rename oldName newName expr) = do
1052− rel <- evalGraphRefRelationalExpr expr
1053− lift $ except $ rename oldName newName rel
1054−evalGraphRefRelationalExpr (Difference exprA exprB) = do
1055− relA <- evalGraphRefRelationalExpr exprA
1056− relB <- evalGraphRefRelationalExpr exprB
1057− lift $ except $ difference relA relB
1058−evalGraphRefRelationalExpr (Group groupAttrNames newAttrName expr) = do
1059− groupNames <- evalGraphRefAttributeNames groupAttrNames expr
1060− rel <- evalGraphRefRelationalExpr expr
1061− lift $ except $ group groupNames newAttrName rel
1062−evalGraphRefRelationalExpr (Ungroup groupAttrName expr) = do
1063− rel <- evalGraphRefRelationalExpr expr
1064− lift $ except $ ungroup groupAttrName rel
1065−evalGraphRefRelationalExpr (Restrict predExpr expr) = do
1066− rel <- evalGraphRefRelationalExpr expr
1067− filt <- predicateRestrictionFilter (attributes rel) predExpr
1068− lift $ except $ restrict filt rel
1069−evalGraphRefRelationalExpr (Equals exprA exprB) = do
1070− relA <- evalGraphRefRelationalExpr exprA
1071− relB <- evalGraphRefRelationalExpr exprB
1072− pure $ if relA == relB then relationTrue else relationFalse
1073−evalGraphRefRelationalExpr (NotEquals exprA exprB) = do
1074− relA <- evalGraphRefRelationalExpr exprA
1075− relB <- evalGraphRefRelationalExpr exprB
1076− pure $ if relA == relB then relationFalse else relationTrue
1077−evalGraphRefRelationalExpr (Extend extendTupleExpr expr) = do
1078− rel <- evalGraphRefRelationalExpr expr
1079− (newAttrs, tupProc) <- extendGraphRefTupleExpressionProcessor rel extendTupleExpr
1080− lift $ except $ relMogrify tupProc newAttrs rel
1081−evalGraphRefRelationalExpr expr@With{} =
1082− --strategy A: add relation variables to the contexts in the graph
1083− --strategy B: drop in macros in place (easier programmatically)
1084− --strategy B implementation
1085− evalGraphRefRelationalExpr (substituteWithNameMacros [] expr)
1087dbContextForTransId :: TransactionId -> TransactionGraph -> Either RelationalError DatabaseContext
1131dbContextForTransId :: TransactionId -> TransactionGraph -> Either RelationalError DatabaseContext
1088dbContextForTransId tid graph = do
1132dbContextForTransId tid graph = do
@@ -1100,120 +1144,169 @@ transactionForId tid graph
1101 matchingTrans = S.filter (\(Transaction idMatch _ _) -> idMatch == tid) (transactionsForGraph graph)
1145 matchingTrans = S.filter (\(Transaction idMatch _ _) -> idMatch == tid) (transactionsForGraph graph)
1103−typeForGraphRefRelationalExpr :: GraphRefRelationalExpr -> GraphRefRelationalExprM Relation
1147+processRestrictionPredicateExpr :: RestrictionPredicateExpr -> RelationalExprState GraphRefRestrictionPredicateExpr
1104−typeForGraphRefRelationalExpr (MakeStaticRelation attrs _) = lift $ except $ mkRelation attrs emptyTupleSet
1148+processRestrictionPredicateExpr TruePredicate = pure TruePredicate
1105−typeForGraphRefRelationalExpr (ExistingRelation rel) = pure (emptyRelationWithAttrs (attributes rel))
1149+processRestrictionPredicateExpr (AndPredicate a b) = AndPredicate <$> processRestrictionPredicateExpr a <*> processRestrictionPredicateExpr b
1106−typeForGraphRefRelationalExpr (MakeRelationFromExprs mAttrExprs tupleExprs) = do
1150+processRestrictionPredicateExpr (OrPredicate a b) = OrPredicate <$> processRestrictionPredicateExpr a <*> processRestrictionPredicateExpr b
1107− mAttrs <- case mAttrExprs of
1151+processRestrictionPredicateExpr (NotPredicate a) = NotPredicate <$> processRestrictionPredicateExpr a
1108− Just attrExprs -> do
1152+processRestrictionPredicateExpr (RelationalExprPredicate expr) =
1109− attrs <- mapM evalGraphRefAttributeExpr attrExprs
1153+ RelationalExprPredicate <$> processRelationalExpr expr
1110− pure (Just (attributesFromList attrs))
1154+processRestrictionPredicateExpr (AtomExprPredicate expr) =
1111− Nothing -> pure Nothing
1155+ AtomExprPredicate <$> processAtomExpr expr
1112− tuples <- evalGraphRefTupleExprs mAttrs tupleExprs
1156+processRestrictionPredicateExpr (AttributeEqualityPredicate nam expr) =
1113− let retAttrs = case tuples of
1157+ AttributeEqualityPredicate nam <$> processAtomExpr expr
1114− (tup:_) -> tupleAttributes tup
1158+
1115− [] -> fromMaybe A.emptyAttributes mAttrs
1159+processExtendTupleExpr :: ExtendTupleExpr -> RelationalExprState GraphRefExtendTupleExpr
1116− pure $ emptyRelationWithAttrs retAttrs
1160+processExtendTupleExpr (AttributeExtendTupleExpr nam atomExpr) =
1117−
1161+ AttributeExtendTupleExpr nam <$> processAtomExpr atomExpr
1163+typeForGraphRefRelationalExpr :: GraphRefRelationalExpr -> RelationalExprState (Either RelationalError Relation)
1164+typeForGraphRefRelationalExpr (MakeStaticRelation attrs _) = pure $ mkRelation attrs emptyTupleSet
1165+typeForGraphRefRelationalExpr (ExistingRelation rel) = pure (Right (emptyRelationWithAttrs (attributes rel)))
1166+typeForGraphRefRelationalExpr (MakeRelationFromExprs mAttrExprs tupleExprs) =
1168+ Just attrExprs -> do
1169+ eAttrs <- mapM (\e -> evalGraphRefAttributeExpr e) attrExprs
1170+ case lefts eAttrs of
1171+ [] -> pure (Right (emptyRelationWithAttrs (attributesFromList (rights eAttrs))))
1172+ _ -> pure (Left (someErrors (lefts eAttrs)))
1118typeForGraphRefRelationalExpr (RelationVariable rvName tid) = do
1173typeForGraphRefRelationalExpr (RelationVariable rvName tid) = do
1119− relVars <- relationVariables <$> gfDatabaseContextForMarker tid
1174+ eTrans <- currentTrans
1120− case M.lookup rvName relVars of
1175+ case eTrans of
1121− Nothing -> throwError (RelVarNotDefinedError rvName)
1176+ Left err -> pure (Left err)
1122− Just rvExpr ->
1177+ Right trans -> do
1123− typeForGraphRefRelationalExpr rvExpr
1178+ let relVars = relationVariables (concreteDatabaseContext trans)
1179+ case M.lookup rvName relVars of
1180+ Nothing -> pure (Left (RelVarNotDefinedError rvName))
1181+ Just rvExpr -> typeForGraphRefRelationalExpr rvExpr
1124typeForGraphRefRelationalExpr (Project attrNames expr) = do
1182typeForGraphRefRelationalExpr (Project attrNames expr) = do
1125− exprType' <- typeForGraphRefRelationalExpr expr
1183+ eExprType <- typeForGraphRefRelationalExpr expr
1126− projectionAttrs <- evalGraphRefAttributeNames attrNames expr
1184+ case eExprType of
1127− lift $ except $ project projectionAttrs exprType'
1185+ Left err -> pure (Left err)
1128−typeForGraphRefRelationalExpr (Union exprA exprB) = do
1186+ Right exprType -> do
1129− exprA' <- typeForGraphRefRelationalExpr exprA
1187+ eProjectionAttrs <- evalGraphRefAttributeNames attrNames expr
1130− exprB' <- typeForGraphRefRelationalExpr exprB
1188+ pure $ case eProjectionAttrs of
1131− lift $ except $ union exprA' exprB'
1189+ Left err -> Left err
1132−typeForGraphRefRelationalExpr (Join exprA exprB) = do
1190+ Right projectionAttrs -> project projectionAttrs exprType
1133− exprA' <- typeForGraphRefRelationalExpr exprA
1191+
1134− exprB' <- typeForGraphRefRelationalExpr exprB
1192+evalGraphRefAttributeNames :: GraphRefAttributeNames -> GraphRefRelationalExpr -> RelationalExprState (Either RelationalError (S.Set AttributeName))
1135− lift $ except $ join exprA' exprB'
1136−typeForGraphRefRelationalExpr (Rename oldAttr newAttr expr) = do
1137− expr' <- typeForGraphRefRelationalExpr expr
1138− lift $ except $ rename oldAttr newAttr expr'
1139−typeForGraphRefRelationalExpr (Difference exprA exprB) = do
1140− exprA' <- typeForGraphRefRelationalExpr exprA
1141− exprB' <- typeForGraphRefRelationalExpr exprB
1142− lift $ except $ difference exprA' exprB'
1143−typeForGraphRefRelationalExpr (Group groupNames attrName expr) = do
1144− expr' <- typeForGraphRefRelationalExpr expr
1145− groupNames' <- evalGraphRefAttributeNames groupNames expr
1146− lift $ except $ group groupNames' attrName expr'
1147−typeForGraphRefRelationalExpr (Ungroup groupAttrName expr) = do
1148− expr' <- typeForGraphRefRelationalExpr expr
1149− lift $ except $ ungroup groupAttrName expr'
1150−typeForGraphRefRelationalExpr (Restrict pred' expr) = do
1151− expr' <- typeForGraphRefRelationalExpr expr
1152− filt <- predicateRestrictionFilter (attributes expr') pred'
1153− lift $ except $ restrict filt expr'
1154−typeForGraphRefRelationalExpr Equals{} =
1156−typeForGraphRefRelationalExpr NotEquals{} =
1158−typeForGraphRefRelationalExpr (Extend extendTupleExpr expr) = do
1159− rel <- typeForGraphRefRelationalExpr expr
1160− evalGraphRefRelationalExpr (Extend extendTupleExpr (ExistingRelation rel))
1161−typeForGraphRefRelationalExpr expr@(With withs _) = do
1162− let expr' = substituteWithNameMacros [] expr
1163− checkMacroName (WithNameExpr macroName tid) = do
1164− rvs <- relationVariables <$> gfDatabaseContextForMarker tid
1165− case M.lookup macroName rvs of
1166− Just _ -> lift $ except $ Left (RelVarAlreadyDefinedError macroName) --this error does not include the transaction marker, but should be good enough to identify the cause
1168− mapM_ (checkMacroName . fst) withs
1169− typeForGraphRefRelationalExpr expr'
1171−evalGraphRefAttributeNames :: GraphRefAttributeNames -> GraphRefRelationalExpr -> GraphRefRelationalExprM (S.Set AttributeName)
1172evalGraphRefAttributeNames attrNames expr = do
1193evalGraphRefAttributeNames attrNames expr = do
1173− exprType' <- typeForGraphRefRelationalExpr expr
1194+ eExprType <- typeForGraphRefRelationalExpr expr
1174− let typeNameSet = S.fromList (V.toList (A.attributeNames (attributes exprType')))
1195+ case eExprType of
1175− case attrNames of
1196+ Left err -> pure (Left err)
1176− AttributeNames names ->
1197+ Right exprTyp -> do
1177− case A.projectionAttributesForNames names (attributes exprType') of
1198+ let typeNameSet = S.fromList (V.toList (A.attributeNames (attributes exprTyp)))
1178− Left err -> throwError err
1199+ case attrNames of
1179− Right attrs -> pure (S.fromList (V.toList (A.attributeNames attrs)))
1200+ AttributeNames names ->
1201+ case A.projectionAttributesForNames names (attributes exprTyp) of
1202+ Left err -> pure (Left err)
1203+ Right attrs -> pure (Right (S.fromList (V.toList (A.attributeNames attrs))))
1181− InvertedAttributeNames names -> do
1205+ InvertedAttributeNames names -> do
1182 let nonExistentAttributeNames = A.attributeNamesNotContained names typeNameSet
1206 let nonExistentAttributeNames = A.attributeNamesNotContained names typeNameSet
1183 if not (S.null nonExistentAttributeNames) then
1207 if not (S.null nonExistentAttributeNames) then
1184− throwError $ AttributeNamesMismatchError nonExistentAttributeNames
1208+ pure (Left (AttributeNamesMismatchError nonExistentAttributeNames))
1186− pure (A.nonMatchingAttributeNameSet names typeNameSet)
1210+ pure (pure (A.nonMatchingAttributeNameSet names typeNameSet))
1188− UnionAttributeNames namesA namesB -> do
1212+ UnionAttributeNames namesA namesB -> do
1189− nameSetA <- evalGraphRefAttributeNames namesA expr
1213+ eNameSetA <- evalGraphRefAttributeNames namesA expr
1190− nameSetB <- evalGraphRefAttributeNames namesB expr
1214+ case eNameSetA of
1191− pure (S.union nameSetA nameSetB)
1215+ Left err -> pure (Left err)
1216+ Right nameSetA -> do
1217+ eNameSetB <- evalGraphRefAttributeNames namesB expr
1219+ Left err -> pure (Left err)
1221+ pure (Right (S.union nameSetA nameSetB))
1193− IntersectAttributeNames namesA namesB -> do
1223+ IntersectAttributeNames namesA namesB -> do
1194− nameSetA <- evalGraphRefAttributeNames namesA expr
1224+ eNameSetA <- evalGraphRefAttributeNames namesA expr
1195− nameSetB <- evalGraphRefAttributeNames namesB expr
1225+ case eNameSetA of
1196− pure (S.intersection nameSetA nameSetB)
1226+ Left err -> pure (Left err)
1227+ Right nameSetA -> do
1228+ eNameSetB <- evalGraphRefAttributeNames namesB expr
1230+ Left err -> pure (Left err)
1232+ pure (Right (S.intersection nameSetA nameSetB))
1234+ RelationalExprAttributeNames attrExpr -> do
1235+ eAttrExprType <- typeForGraphRefRelationalExpr attrExpr
1236+ case eAttrExprType of
1237+ Left err -> pure (Left err)
1238+ Right attrExprType -> pure (Right (A.attributeNameSet (attributes attrExprType)))
1198− RelationalExprAttributeNames attrExpr -> do
1199− attrExprType <- typeForGraphRefRelationalExpr attrExpr
1200− pure (A.attributeNameSet (attributes attrExprType))
1202−evalGraphRefAttributeExpr :: GraphRefAttributeExpr -> GraphRefRelationalExprM Attribute
1241+
1243+processAtomExpr :: AtomExpr -> RelationalExprState GraphRefAtomExpr
1244+processAtomExpr (AttributeAtomExpr nam) = pure $ AttributeAtomExpr nam
1245+processAtomExpr (NakedAtomExpr atom) = pure $ NakedAtomExpr atom
1246+processAtomExpr (FunctionAtomExpr fName atomExprs ()) = do
1247+ tid <- re_currentTransId <$> askEnv
1248+ FunctionAtomExpr fName <$> mapM processAtomExpr atomExprs <*> pure tid
1249+processAtomExpr (RelationAtomExpr expr) = RelationAtomExpr <$> processRelationalExpr expr
1250+processAtomExpr (ConstructedAtomExpr dConsName atomExprs ()) = ConstructedAtomExpr dConsName <$> mapM processAtomExpr atomExprs <*> (re_currentTransId <$> askEnv)
1252+processTupleExpr :: TupleExpr -> RelationalExprState GraphRefTupleExpr
1253+processTupleExpr (TupleExpr tMap) =
1254+ TupleExpr . M.fromList <$> mapM (\(k,v) -> (,) k <$> processAtomExpr v) (M.toList tMap)
1256+evalGraphRefAttributeExpr :: GraphRefAttributeExpr -> RelationalExprState (Either RelationalError Attribute)
1203evalGraphRefAttributeExpr (AttributeAndTypeNameExpr attrName tCons tid) = do
1257evalGraphRefAttributeExpr (AttributeAndTypeNameExpr attrName tCons tid) = do
1204− tConsMap <- typeConstructorMapping <$> gfDatabaseContextForMarker tid
1258+ graph <- re_graph <$> askEnv
1205− case atomTypeForTypeConstructorValidate True tCons tConsMap M.empty of
1259+ case transactionForId tid graph of
1206− Left err -> throwError err
1260+ Left err -> pure (Left err)
1207− Right aType -> do
1261+ Right trans -> do
1208− case validateAtomType aType tConsMap of
1262+ let tConsMap = typeConstructorMapping (concreteDatabaseContext trans)
1209− Left err -> throwError err
1263+ case atomTypeForTypeConstructorValidate True tCons tConsMap M.empty of
1210− Right _ -> pure (Attribute attrName aType)
1264+ Left err -> pure (Left err)
1211−evalGraphRefAttributeExpr (NakedAttributeExpr attr) = pure attr
1265+ Right aType -> do
1266+ case validateAtomType aType tConsMap of
1267+ Left err -> pure (Left err)
1268+ Right _ -> pure (Right (Attribute attrName aType))
1270+--convert AttributeExpr to GraphRefAttributeExpr
1271+processAttributeExpr :: AttributeExpr -> RelationalExprState GraphRefAttributeExpr
1272+processAttributeExpr (AttributeAndTypeNameExpr nam tCons ()) = do
1273+ tid <- re_currentTransId <$> askEnv
1274+ pure $ AttributeAndTypeNameExpr nam tCons tid
1275+processAttributeExpr (NakedAttributeExpr attr) = pure $ NakedAttributeExpr attr
1277+-- convert a RelationalExpr into a GraphRefRelationalExpr using the current trans Id
1278+-- can this be done without any RelationalErrors as opposed to evalRelationalExpr?
1279+processRelationalExpr :: RelationalExpr -> RelationalExprState GraphRefRelationalExpr
1280+processRelationalExpr (MakeRelationFromExprs mAttrs tupleExprs) = do
1281+ mAttrs' <- case mAttrs of
1282+ Nothing -> pure Nothing
1283+ Just mAttrs'' -> Just <$> mapM processAttributeExpr mAttrs''
1284+ MakeRelationFromExprs mAttrs' <$> mapM processTupleExpr tupleExprs
1285+processRelationalExpr (MakeStaticRelation attrs tupSet) = pure (MakeStaticRelation attrs tupSet)
1286+processRelationalExpr (ExistingRelation rel) = pure (ExistingRelation rel)
1287+processRelationalExpr (RelationVariable rv ()) = RelationVariable rv <$> fmap re_currentTransId askEnv
1288+processRelationalExpr (Project attrNames expr) = Project <$> processAttributeNames attrNames <*> processRelationalExpr expr
1289+processRelationalExpr (Union exprA exprB) = Union <$> processRelationalExpr exprA <*> processRelationalExpr exprB
1290+processRelationalExpr (Join exprA exprB) = Join <$> processRelationalExpr exprA <*> processRelationalExpr exprB
1291+processRelationalExpr (Rename attrA attrB expr) =
1292+ Rename attrA attrB <$> processRelationalExpr expr
1293+processRelationalExpr (Difference exprA exprB) = Difference <$> processRelationalExpr exprA <*> processRelationalExpr exprB
1294+processRelationalExpr (Group attrNames attrName expr) = Group <$> processAttributeNames attrNames <*> pure attrName <*> processRelationalExpr expr
1295+processRelationalExpr (Ungroup attrName expr) = Ungroup attrName <$> processRelationalExpr expr
1296+processRelationalExpr (Restrict pred expr) = Restrict <$> processRestrictionPredicateExpr pred <*> processRelationalExpr expr
1297+processRelationalExpr (Equals exprA exprB) =
1298+ Equals <$> processRelationalExpr exprA <*> processRelationalExpr exprB
1299+processRelationalExpr (NotEquals exprA exprB) =
1300+ NotEquals <$> processRelationalExpr exprA <*> processRelationalExpr exprB
1301+processRelationalExpr (Extend extendExpr expr) =
1302+ Extend <$> processExtendTupleExpr extendExpr <*> processRelationalExpr expr
1303+processRelationalExpr (With macros expr) =
1304+ With <$> mapM (\(nam, wexpr) -> (,) nam <$> processRelationalExpr wexpr) macros <*> processRelationalExpr expr
1213mkEmptyRelVars :: RelationVariables -> RelationVariables
1306mkEmptyRelVars :: RelationVariables -> RelationVariables
1214−mkEmptyRelVars = M.map mkEmptyRelVar
1307+mkEmptyRelVars rvMap = M.map mkEmptyRelVar rvMap
1216− mkEmptyRelVar expr@MakeRelationFromExprs{} = expr --do not truncate here because we might lose essential type information in emptying the tuples
1309+ mkEmptyRelVar (MakeRelationFromExprs mAttrs _) = MakeRelationFromExprs mAttrs []
1217 mkEmptyRelVar (MakeStaticRelation attrs _) = MakeStaticRelation attrs emptyTupleSet
1310 mkEmptyRelVar (MakeStaticRelation attrs _) = MakeStaticRelation attrs emptyTupleSet
1218 mkEmptyRelVar (ExistingRelation rel) = ExistingRelation (emptyRelationWithAttrs (attributes rel))
1311 mkEmptyRelVar (ExistingRelation rel) = ExistingRelation (emptyRelationWithAttrs (attributes rel))
1219 mkEmptyRelVar rv@RelationVariable{} = Restrict (NotPredicate TruePredicate) rv
1312 mkEmptyRelVar rv@RelationVariable{} = Restrict (NotPredicate TruePredicate) rv
@@ -1224,169 +1317,53 @@ mkEmptyRelVars = M.map mkEmptyRelVar
1224 mkEmptyRelVar (Difference exprA exprB) = Difference (mkEmptyRelVar exprA) (mkEmptyRelVar exprB)
1317 mkEmptyRelVar (Difference exprA exprB) = Difference (mkEmptyRelVar exprA) (mkEmptyRelVar exprB)
1225 mkEmptyRelVar (Group attrNames attrName expr) = Group attrNames attrName (mkEmptyRelVar expr)
1318 mkEmptyRelVar (Group attrNames attrName expr) = Group attrNames attrName (mkEmptyRelVar expr)
1226 mkEmptyRelVar (Ungroup attrName expr) = Ungroup attrName (mkEmptyRelVar expr)
1319 mkEmptyRelVar (Ungroup attrName expr) = Ungroup attrName (mkEmptyRelVar expr)
1227− mkEmptyRelVar (Restrict pred' expr) = Restrict pred' (mkEmptyRelVar expr)
1320+ mkEmptyRelVar (Restrict pred expr) = Restrict pred (mkEmptyRelVar expr)
1228 mkEmptyRelVar (Equals exprA exprB) = Equals (mkEmptyRelVar exprA) (mkEmptyRelVar exprB)
1321 mkEmptyRelVar (Equals exprA exprB) = Equals (mkEmptyRelVar exprA) (mkEmptyRelVar exprB)
1229 mkEmptyRelVar (NotEquals exprA exprB) = NotEquals (mkEmptyRelVar exprA) (mkEmptyRelVar exprB)
1322 mkEmptyRelVar (NotEquals exprA exprB) = NotEquals (mkEmptyRelVar exprA) (mkEmptyRelVar exprB)
1230 mkEmptyRelVar (Extend extTuple expr) = Extend extTuple (mkEmptyRelVar expr)
1323 mkEmptyRelVar (Extend extTuple expr) = Extend extTuple (mkEmptyRelVar expr)
1231− mkEmptyRelVar (With macros expr) = With (map (second mkEmptyRelVar) macros) (mkEmptyRelVar expr)
1324+ mkEmptyRelVar (With macros expr) = With (map (\(rv, expr) -> (rv, mkEmptyRelVar expr)) macros) (mkEmptyRelVar expr)
1326+processAttributeNames :: AttributeNames -> RelationalExprState GraphRefAttributeNames
1327+processAttributeNames (AttributeNames nameSet) = pure $ AttributeNames nameSet
1328+processAttributeNames (UnionAttributeNames attrNamesA attrNamesB) = UnionAttributeNames <$> processAttributeNames attrNamesA <*> processAttributeNames attrNamesB
1329+processAttributeNames (IntersectAttributeNames attrNamesA attrNamesB) = IntersectAttributeNames <$> processAttributeNames attrNamesA <*> processAttributeNames attrNamesB
1330+processAttributeNames (RelationalExprAttributeNames expr) = RelationalExprAttributeNames <$> processRelationalExpr expr
1332+processDatabaseContextExpr :: DatabaseContextExpr -> RelationalExprState GraphRefDatabaseContextExpr
1333+processDatabaseContextExpr expr =
1335+ NoOperation -> pure NoOperation
1336+ Define nam attrExprs -> Define nam <$> mapM processAttributeExpr attrExprs
1337+ Undefine nam -> pure (Undefine nam)
1338+ Assign nam rexpr -> Assign nam <$> processRelationalExpr rexpr
1339+ Insert nam rexpr -> Insert nam <$> processRelationalExpr rexpr
1340+ Delete nam pred -> Delete nam <$> processRestrictionPredicateExpr pred
1341+ Update nam attrMap pred -> Update nam attrMap <$> processRestrictionPredicateExpr pred
1343+ AddInclusionDependency nam dep -> pure (AddInclusionDependency nam dep)
1344+ RemoveInclusionDependency nam -> pure (RemoveInclusionDependency nam)
1345+ AddNotification nam exprA exprB exprC -> pure (AddNotification nam exprA exprB exprC)
1346+ RemoveNotification nam -> pure (RemoveNotification nam)
1347+ AddTypeConstructor tyDef consDefs -> pure (AddTypeConstructor tyDef consDefs)
1348+ RemoveTypeConstructor tyName -> pure (RemoveTypeConstructor tyName)
1350+ RemoveAtomFunction aFuncName -> pure (RemoveAtomFunction aFuncName)
1351+ RemoveDatabaseContextFunction funcName -> pure (RemoveDatabaseContextFunction funcName)
1352+ ExecuteDatabaseContextFunction funcName atomExprs -> ExecuteDatabaseContextFunction funcName <$> mapM processAtomExpr atomExprs
1353+ MultipleExpr exprs -> MultipleExpr <$> mapM processDatabaseContextExpr exprs
1234dbErr :: RelationalError -> DatabaseContextEvalMonad ()
1355dbErr :: RelationalError -> DatabaseContextEvalMonad ()
1235dbErr err = lift (except (Left err))
1356dbErr err = lift (except (Left err))
1237−-- | Return a Relation describing the relation variables.
1358+processDatabaseContextIOExpr :: DatabaseContextIOExpr -> RelationalExprState GraphRefDatabaseContextIOExpr
1238−relationVariablesAsRelation :: DatabaseContext -> TransactionGraph -> Either RelationalError Relation
1359+processDatabaseContextIOExpr (AddAtomFunction f tcs sc) =
1239−relationVariablesAsRelation ctx graph = do
1360+ pure (AddAtomFunction f tcs sc)
1240− let subrelAttrs = A.attributesFromList [Attribute "attribute" TextAtomType, Attribute "type" TextAtomType]
1361+processDatabaseContextIOExpr (LoadAtomFunctions mod fun file) =
1241− attrs = A.attributesFromList [Attribute "name" TextAtomType,
1362+ pure (LoadAtomFunctions mod fun file)
1242− Attribute "attributes" (RelationAtomType subrelAttrs)]
1363+processDatabaseContextIOExpr (AddDatabaseContextFunction mod fun path) =
1243− relVars = relationVariables ctx
1364+ pure (AddDatabaseContextFunction mod fun path)
1244− mkRvDesc (rvName, gfExpr) = do
1365+processDatabaseContextIOExpr (LoadDatabaseContextFunctions mod fun path) =
1245− let gfEnv = freshGraphRefRelationalExprEnv (Just ctx) graph
1366+ pure (LoadDatabaseContextFunctions mod fun path)
1246− gfType <- runGraphRefRelationalExprM gfEnv (typeForGraphRefRelationalExpr gfExpr)
1367+processDatabaseContextIOExpr (CreateArbitraryRelation rvName attrExprs range) =
1247− pure (rvName, gfType)
1368+ CreateArbitraryRelation rvName <$> mapM processAttributeExpr attrExprs <*> pure range
1248− relVarToAtomList (rvName, rel) = [TextAtom rvName, attributesToRel (attributesVec (attributes rel))]
1249− attrAtoms a = [TextAtom (A.attributeName a), TextAtom (prettyAtomType (A.atomType a))]
1250− attributesToRel attrl = case mkRelationFromList subrelAttrs (map attrAtoms (V.toList attrl)) of
1251− Left err -> error ("relationVariablesAsRelation pooped " ++ show err)
1252− Right rel -> RelationAtom rel
1253− rvs <- mapM mkRvDesc (M.toList relVars)
1254− let tups = map relVarToAtomList rvs
1255− mkRelationFromList attrs tups
1257−-- | An unoptimized variant of evalGraphRefRelationalExpr for testing.
1258−evalRelationalExpr :: RelationalExpr -> RelationalExprM Relation
1259−evalRelationalExpr expr = do
1261− context <- reContext
1262− let expr' = runProcessExprM UncommittedContextMarker (processRelationalExpr expr)
1263− gfEnv = freshGraphRefRelationalExprEnv (Just context) graph
1264− case runGraphRefRelationalExprM gfEnv (evalGraphRefRelationalExpr expr') of
1265− Left err -> throwError err
1266− Right rel -> pure rel
1268−class (MonadError RelationalError m, Monad m) => DatabaseContextM m where
1269− getContext :: m DatabaseContext
1271−instance DatabaseContextM (ReaderT GraphRefRelationalExprEnv (ExceptT RelationalError Identity)) where
1272− getContext = gfDatabaseContextForMarker UncommittedContextMarker
1274−instance DatabaseContextM (RWST DatabaseContextEvalEnv () DatabaseContextEvalState (ExceptT RelationalError Identity)) where
1275− getContext = getStateContext
1277−relVarByName :: DatabaseContextM m => RelVarName -> m GraphRefRelationalExpr
1278−relVarByName rvName = do
1279− relvars <- relationVariables <$> getContext
1280− case M.lookup rvName relvars of
1281− Nothing -> throwError (RelVarNotDefinedError rvName)
1282− Just gfexpr -> pure gfexpr
1284−-- | resolve UncommittedTransactionMarker whenever possible- this is important in the DatabaseContext in order to mitigate self-referencing loops for updates
1285−class ResolveGraphRefTransactionMarker a where
1286− resolve :: a -> DatabaseContextEvalMonad a
1289−instance ResolveGraphRefTransactionMarker GraphRefRelationalExpr where
1290− resolve (MakeRelationFromExprs mAttrs tupleExprs) =
1291− MakeRelationFromExprs mAttrs <$> resolve tupleExprs
1292− resolve orig@MakeStaticRelation{} = pure orig
1293− resolve orig@ExistingRelation{} = pure orig
1294− resolve orig@(RelationVariable rvName UncommittedContextMarker) = do
1295− rvMap <- relationVariables <$> getStateContext
1296− case M.lookup rvName rvMap of
1297− Nothing -> pure orig
1298− Just resolvedRv -> resolve resolvedRv
1299− resolve orig@RelationVariable{} = pure orig
1300− resolve (Project attrNames relExpr) = Project <$> resolve attrNames <*> resolve relExpr
1301− resolve (Union exprA exprB) = Union <$> resolve exprA <*> resolve exprB
1302− resolve (Join exprA exprB) = Join <$> resolve exprA <*> resolve exprB
1303− resolve (Rename attrA attrB expr) = Rename attrA attrB <$> resolve expr
1304− resolve (Difference exprA exprB) = Difference <$> resolve exprA <*> resolve exprB
1305− resolve (Group namesA nameB expr) = Group <$> resolve namesA <*> pure nameB <*> resolve expr
1306− resolve (Ungroup nameA expr) = Ungroup nameA <$> resolve expr
1307− resolve (Restrict restrictExpr relExpr) = Restrict <$> resolve restrictExpr <*> resolve relExpr
1308− resolve (Equals exprA exprB) = Equals <$> resolve exprA <*> resolve exprB
1309− resolve (NotEquals exprA exprB) = NotEquals <$> resolve exprA <*> resolve exprB
1310− resolve (Extend extendExpr relExpr) = Extend <$> resolve extendExpr <*> resolve relExpr
1311− resolve (With withExprs relExpr) = With <$> mapM (\(nam, expr) -> (,) <$> resolve nam <*> resolve expr) withExprs <*> resolve relExpr
1313−instance ResolveGraphRefTransactionMarker GraphRefTupleExprs where
1314− resolve (TupleExprs marker tupleExprs) =
1315− TupleExprs marker <$> mapM resolve tupleExprs
1317−instance ResolveGraphRefTransactionMarker GraphRefTupleExpr where
1318− resolve (TupleExpr tupMap) = do
1319− tupMap' <- mapM (\(attrName, expr) -> (,) attrName <$> resolve expr ) (M.toList tupMap)
1320− pure (TupleExpr (M.fromList tupMap'))
1322−instance ResolveGraphRefTransactionMarker GraphRefAttributeNames where
1323− resolve orig@AttributeNames{} = pure orig
1324− resolve orig@InvertedAttributeNames{} = pure orig
1325− resolve (UnionAttributeNames namesA namesB) = UnionAttributeNames <$> resolve namesA <*> resolve namesB
1326− resolve (IntersectAttributeNames namesA namesB) = IntersectAttributeNames <$> resolve namesA <*> resolve namesB
1327− resolve (RelationalExprAttributeNames expr) = RelationalExprAttributeNames <$> resolve expr
1329−instance ResolveGraphRefTransactionMarker GraphRefRestrictionPredicateExpr where
1330− resolve TruePredicate = pure TruePredicate
1331− resolve (AndPredicate exprA exprB) = AndPredicate <$> resolve exprA <*> resolve exprB
1332− resolve (OrPredicate exprA exprB) = OrPredicate <$> resolve exprA <*> resolve exprB
1333− resolve (NotPredicate expr) = NotPredicate <$> resolve expr
1334− resolve (RelationalExprPredicate expr) = RelationalExprPredicate <$> resolve expr
1335− resolve (AtomExprPredicate expr) = AtomExprPredicate <$> resolve expr
1336− resolve (AttributeEqualityPredicate nam expr)= AttributeEqualityPredicate nam <$> resolve expr
1338−instance ResolveGraphRefTransactionMarker GraphRefExtendTupleExpr where
1339− resolve (AttributeExtendTupleExpr nam atomExpr) = AttributeExtendTupleExpr nam <$> resolve atomExpr
1341−instance ResolveGraphRefTransactionMarker GraphRefWithNameExpr where
1342− resolve orig@WithNameExpr{} = pure orig -- match uncommitted marker?
1344−instance ResolveGraphRefTransactionMarker GraphRefAtomExpr where
1345− resolve orig@AttributeAtomExpr{} = pure orig
1346− resolve orig@NakedAtomExpr{} = pure orig
1347− resolve (FunctionAtomExpr nam atomExprs marker) =
1348− FunctionAtomExpr nam <$> mapM resolve atomExprs <*> pure marker
1349− resolve (RelationAtomExpr expr) = RelationAtomExpr <$> resolve expr
1350− resolve (ConstructedAtomExpr dConsName atomExprs marker) =
1351− ConstructedAtomExpr dConsName <$> mapM resolve atomExprs <*> pure marker
1353−--convert series of simple Union queries into MakeStaticRelation
1354−-- this is especially useful for long, nested applications of Union with simple tuples
1355−-- Union (MakeRelation x y) (MakeRelation x y') -> MakeRelation x (y + y')
1357−--MakeRelationFromExprs Nothing (TupleExprs UncommittedContextMarker [TupleExpr (fromList [("name", NakedAtomExpr (TextAtom "steve"))])])
1359−applyUnionCollapse :: GraphRefRelationalExpr -> GraphRefRelationalExpr
1360−applyUnionCollapse = Fold.cata opt
1362− opt :: RelationalExprBaseF GraphRefTransactionMarker GraphRefRelationalExpr -> GraphRefRelationalExpr
1363− opt (UnionF exprA exprB) | exprA == exprB = exprA
1365− exprA@(MakeRelationFromExprs mAttrs1 tupExprs1)
1366− exprB@(MakeRelationFromExprs mAttrs2 tupExprs2)) | tupExprs1 == tupExprs2 = MakeRelationFromExprs (mAttrs1 <|> mAttrs2) tupExprs1
1367− | tupExprsNull tupExprs1 = exprB
1368− | tupExprsNull tupExprs2 = exprA
1369− opt x = Fold.embed x
1370− tupExprsNull (TupleExprs _ []) = True
1371− tupExprsNull _ = False
1374−--UPDATE optimization- find matching where clause in "lower" levels of renaming
1375−--update x where y=1 set (x:=5,z:=10); update x where y=1 set(x:=6,z:=11)
1377−-- update x where y=1 set (x:=6,z:=11)
1378−-- future opt: match individual attributes update x where y=1 set (x:=5); update x where y=1 set (z:=11) => update x where y=1 set (x:=5,z:=11)
1380−--strategy: try to collapse the top-level update (union (restrict pred MakeRelationFromExpr) expr) if it contains the same predicate and resultant relation
1382−--DELETE optimization
1383−-- if a restriction matches a previous restriction, combine them
1384−-- O(1) since it only scans at the top level, critical in benchmarks generating redundant deletions
1385−applyRestrictionCollapse :: GraphRefRelationalExpr -> GraphRefRelationalExpr
1386−applyRestrictionCollapse orig@(Restrict npred@(NotPredicate _) expr) =
1388− orig'@(Restrict npred'@(NotPredicate _) _) | npred == npred' -> orig'
1390−applyRestrictionCollapse expr = expr