3e7015f · project-m36 · git.iko.soy

git.iko.soy/project-m36

add ":p" to show the execution plan

commit3e7015f37d4695392117344b574f9ce26bbf475e authorAgentM <agentm@themactionfaction.com> dateThu 5 Feb 2015, 16:54 (12 years ago) parente9350a5

2 files changed+19

compare with master

unifiedsplit

README.markdown+6 TutorialDInterpreter.hs+13

README.markdown+6

@@ -59,6 +59,12 @@ fromList []

5959```

6060which displays database constraints.

6161

62+ ```

63+TutorialD: :p x:=S{CITY,S#,SNAME,STATUS}

64+Right (Assign "x" (RelationVariable "S"))

65+```

66+which displays the optimized execution plan which would have been executed to evaluate the expression.

67+

62683. expressions which modify the database context such as:

6369

6470 ```

TutorialDInterpreter.hs+13

@@ -248,6 +248,7 @@ data TutorialDOperator where

248248 ShowRelation :: RelationalExpr -> TutorialDOperator

249249 ShowRelationType :: RelationalExpr -> TutorialDOperator

250250 ShowConstraint :: String -> TutorialDOperator

251+ ShowPlan :: DatabaseExpr -> TutorialDOperator

251252 Quit :: TutorialDOperator

252253 deriving (Show)

253254

@@ -263,6 +264,12 @@ showRelP = do

263264 expr <- relExpr

264265 return $ ShowRelation expr

265266

267+showPlanP :: Parser TutorialDOperator

268+showPlanP = do

269+ reservedOp ":p"

270+ expr <- databaseExpr

271+ return $ ShowPlan expr

272+

266273quitP :: Parser TutorialDOperator

267274quitP = do

268275 reservedOp ":q"

@@ -278,6 +285,7 @@ interpreterOps :: Parser TutorialDOperator

278285interpreterOps = typeP

279286 <|> showRelP

280287 <|> showConstraintsP

288+ <|> showPlanP

281289 <|> quitP

282290

283291showRelationAttributes :: Relation -> String

@@ -312,6 +320,11 @@ evalTutorialDOp context (ShowConstraint name) = do

312320 "" -> deps

313321 name -> HS.filter (\(InclusionDependency n _ _) -> n == name) deps

314322

323+evalTutorialDOp context (ShowPlan dbExpr) = do

324+ DisplayResult $ show plan

325+ where

326+ plan = evalState (applyStaticDatabaseOptimization dbExpr) context

327+

315328evalTutorialDOp context (Quit) = QuitResult

316329

317330example1 = "relA {a,b, c}"