e5dd493 · squeal · git.iko.soy

git.iko.soy/squeal

on dev help sign in

some aggregate stuff

e5dd493Eitan Chatav8 years ago

squeal-postgresql/src/Squeal/PostgreSQL/Expression.hs+46−45

compare with dev

unifiedsplit

@@ -136,7 +136,7 @@ module Squeal.PostgreSQL.Expression

136 -- ** Aggregation

137 , Aggregate (..)

138 , DistinctExpression (..)

139− , PGAvg (avg, avgDistinct)

139+ , PGAvg

140 , countStar

141 -- * Window Functions

142 , WindowDefinition (..)

@@ -261,7 +261,7 @@ class KnownNat n => HasParameter

261 | n params -> ty where

262 -- | `parameter` takes a `Nat` using type application and a `TypeExpression`.

263 --

264− -- >>> let expr = parameter @1 int4 :: Expression '[] schemas '[ 'Null 'PGint4] grp from ('Null 'PGint4)

264+ -- >>> let expr = parameter @1 int4 :: Expression grp '[] schemas '[ 'Null 'PGint4] from ('Null 'PGint4)

265 -- >>> printSQL expr

266 -- ($1 :: int4)

267 parameter

@@ -277,7 +277,7 @@ instance {-# OVERLAPPABLE #-} (KnownNat n, HasParameter (n-1) params ty)

277-- | `param` takes a `Nat` using type application and for basic types,

278-- infers a `TypeExpression`.

279--

280−-- >>> let expr = param @1 :: Expression commons schemas '[ 'Null 'PGint4] grp from ('Null 'PGint4)

280+-- >>> let expr = param @1 :: Expression grp commons schemas '[ 'Null 'PGint4] from ('Null 'PGint4)

281-- >>> printSQL expr

282-- ($1 :: int4)

283param

@@ -436,7 +436,7 @@ matchNull y f x = ifThenElse (isNull x) y

436`nullIf` gives @NULL@.

437

438>>> :set -XTypeApplications -XDataKinds

439−>>> let expr = nullIf false (param @1) :: Expression commons schemas '[ 'NotNull 'PGbool] grp from ('Null 'PGbool)

439+>>> let expr = nullIf false (param @1) :: Expression grp commons schemas '[ 'NotNull 'PGbool] from ('Null 'PGbool)

440>>> printSQL expr

441NULL IF (FALSE, ($1 :: bool))

442-}

@@ -498,7 +498,7 @@ row exprs = UnsafeExpression $ "ROW" <> parenthesized

498-- type Schema = '["complex" ::: 'Typedef Complex]

499-- :}

500--

501−-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression '[] (Public Schema) from grp params ('NotNull Complex)

501+-- >>> let i = row (0 `as` #real :* 1 `as` #imaginary) :: Expression grp '[] (Public Schema) from params ('NotNull Complex)

502-- >>> printSQL $ i & field #complex #imaginary

503-- (ROW(0, 1)::"complex")."imaginary"

504field

@@ -522,7 +522,7 @@ instance Monoid

522 mempty = array []

523 mappend = (<>)

524

525−-- | >>> let expr = greatest currentTimestamp [param @1] :: Expression commons schemas '[ 'NotNull 'PGtimestamptz] grp from ('NotNull 'PGtimestamptz)

525+-- | >>> let expr = greatest currentTimestamp [param @1] :: Expression grp commons schemas '[ 'NotNull 'PGtimestamptz] from ('NotNull 'PGtimestamptz)

526-- >>> printSQL expr

527-- GREATEST(CURRENT_TIMESTAMP, ($1 :: timestamp with time zone))

528greatest

@@ -1398,7 +1398,7 @@ class Aggregate expr aggr where

1398

1399 -- | >>> :{

1400 -- let

1401− -- expression :: Expression commons schemas params (Grouped bys) '[tab ::: '["col" ::: nullity ty]] ('NotNull 'PGint8)

1401+ -- expression :: Expression (Grouped bys) commons schemas params '[tab ::: '["col" ::: nullity ty]] ('NotNull 'PGint8)

1402 -- expression = count #col

1403 -- in printSQL expression

1404 -- :}

@@ -1484,23 +1484,37 @@ class Aggregate expr aggr where

1484 -- ^ what to aggregate

1485 -> aggr commons schemas params from (nullity 'PGbool)

1486

1487− -- | minimum and maximum aggregation

1487+ -- | maximum aggregation

1488− max_, min_

1488+ max_

1489 :: expr commons schemas params from (nullity ty)

1490− -- ^ what to aggregate

1490+ -- ^ what to maximize

1491 -> aggr commons schemas params from (nullity ty)

1492

1493+ -- | minimum aggregation

1494+ min_

1495+ :: expr commons schemas params from (nullity ty)

1496+ -- ^ what to minimize

1497+ -> aggr commons schemas params from (nullity ty)

1498+

1499+ -- | average aggregation

1500+ avg

1501+ :: expr commons schemas params from (nullity ty)

1502+ -- ^ what to average

1503+ -> aggr commons schemas params from (nullity (PGAvg ty))

1504+

1493−instance Aggregate (Expression 'Ungrouped) (Expression ('Grouped bys)) where

1505+instance {-# OVERLAPPABLE #-} expr ~ (Expression 'Ungrouped)

1506+ => Aggregate expr (Expression ('Grouped bys)) where

1494− count = unsafeAggregate "count"

1507+ count = unsafeAggregate "count"

1495− sum_ = unsafeAggregate "sum"

1508+ sum_ = unsafeAggregate "sum"

1496− bitAnd = unsafeAggregate "bit_and"

1509+ bitAnd = unsafeAggregate "bit_and"

1497− bitOr = unsafeAggregate "bit_or"

1510+ bitOr = unsafeAggregate "bit_or"

1498− boolAnd = unsafeAggregate "bool_and"

1511+ boolAnd = unsafeAggregate "bool_and"

1499− boolOr = unsafeAggregate "bool_or"

1512+ boolOr = unsafeAggregate "bool_or"

1500− every = unsafeAggregate "every"

1513+ every = unsafeAggregate "every"

1501− max_ = unsafeAggregate "max"

1514+ max_ = unsafeAggregate "max"

1502− min_ = unsafeAggregate "min"

1515+ min_ = unsafeAggregate "min"

1516+ avg = unsafeAggregate "avg"

1503−instance Aggregate DistinctExpression (Expression ('Grouped bys)) where

1517+instance {-# OVERLAPPING #-} Aggregate DistinctExpression (Expression ('Grouped bys)) where

1504 count = unsafeAggregate "count"

1518 count = unsafeAggregate "count"

1505 sum_ = unsafeAggregate "sum"

1519 sum_ = unsafeAggregate "sum"

1506 bitAnd = unsafeAggregate "bit_and"

1520 bitAnd = unsafeAggregate "bit_and"

@@ -1510,6 +1524,7 @@ instance Aggregate DistinctExpression (Expression ('Grouped bys)) where

1510 every = unsafeAggregate "every"

1524 every = unsafeAggregate "every"

1511 max_ = unsafeAggregate "max"

1525 max_ = unsafeAggregate "max"

1512 min_ = unsafeAggregate "min"

1526 min_ = unsafeAggregate "min"

1527+ avg = unsafeAggregate "avg"

1513instance Aggregate (Expression grp) (WindowFunction grp) where

1528instance Aggregate (Expression grp) (WindowFunction grp) where

1514 count = unsafeWindowFunction1 "count"

1529 count = unsafeWindowFunction1 "count"

1515 sum_ = unsafeWindowFunction1 "sum"

1530 sum_ = unsafeWindowFunction1 "sum"

@@ -1520,6 +1535,7 @@ instance Aggregate (Expression grp) (WindowFunction grp) where

1520 every = unsafeWindowFunction1 "every"

1535 every = unsafeWindowFunction1 "every"

1521 max_ = unsafeWindowFunction1 "max"

1536 max_ = unsafeWindowFunction1 "max"

1522 min_ = unsafeWindowFunction1 "min"

1537 min_ = unsafeWindowFunction1 "min"

1538+ avg = unsafeWindowFunction1 "avg"

1523

1539

1524newtype DistinctExpression commons schemas params from ty

1540newtype DistinctExpression commons schemas params from ty

1525 = Distinct (Expression 'Ungrouped commons schemas params from ty)

1541 = Distinct (Expression 'Ungrouped commons schemas params from ty)

@@ -1536,30 +1552,15 @@ unsafeAggregate

1536unsafeAggregate fun x = UnsafeExpression $ mconcat

1552unsafeAggregate fun x = UnsafeExpression $ mconcat

1537 [fun, "(", renderSQL x, ")"]

1553 [fun, "(", renderSQL x, ")"]

1538

1554

1539−-- | escape hatch to define aggregate functions over distinct values

1555+-- | A type family that calculates `PGAvg` type of a `PGType`.

1540−unsafeAggregateDistinct

1556+type family PGAvg ty where

1541− :: ByteString -- ^ aggregate function

1542− -> Expression 'Ungrouped commons schemas params from xty

1543− -> Expression ('Grouped bys) commons schemas params from yty

1544−unsafeAggregateDistinct fun x = UnsafeExpression $ mconcat

1545− [fun, "(DISTINCT ", renderSQL x, ")"]

1546−

1547−-- | A constraint for `PGType`s that you can take averages of and the resulting

1548−-- `PGType`.

1549−class PGAvg ty avg | ty -> avg where

1550− avg, avgDistinct

1551− :: Expression 'Ungrouped commons schemas params from (nullity ty)

1552− -- ^ what to average

1553− -> Expression ('Grouped bys) commons schemas params from (nullity avg)

1554− avg = unsafeAggregate "avg"

1555− avgDistinct = unsafeAggregateDistinct "avg"

1556−instance PGAvg 'PGint2 'PGnumeric

1557+ PGAvg 'PGint2 = 'PGnumeric

1557−instance PGAvg 'PGint4 'PGnumeric

1558+ PGAvg 'PGint4 = 'PGnumeric

1558−instance PGAvg 'PGint8 'PGnumeric

1559+ PGAvg 'PGint8 = 'PGnumeric

1559−instance PGAvg 'PGnumeric 'PGnumeric

1560+ PGAvg 'PGnumeric = 'PGnumeric

1560−instance PGAvg 'PGfloat4 'PGfloat8

1561+ PGAvg 'PGfloat4 = 'PGfloat8

1561−instance PGAvg 'PGfloat8 'PGfloat8

1562+ PGAvg 'PGfloat8 = 'PGfloat8

1562−instance PGAvg 'PGinterval 'PGinterval

1563+ PGAvg 'PGinterval = 'PGinterval

1563

1564

1564-- | A special aggregation that does not require an input

1565-- | A special aggregation that does not require an input

1565--

1566--