43bf3a4 · rel8 · git.iko.soy

git.iko.soy/rel8

Add headAgg aggregation function

commit43bf3a404bbdd424dd90037b11d2dc7baae8dcc0 authorShane O'Brien <shane.obrien@circuithub.com> dateSun 13 Jun 2021, 23:52 (5 years ago) parent5a45f67

4 files changed+37−4

compare with master

unifiedsplit

src/Rel8.hs+2−1 src/Rel8/Aggregate/Legacy.hs+12−2 src/Rel8/Expr/Aggregate.hs+15 src/Rel8/Table/Aggregate.hs+8−1

src/Rel8.hs+2−1

@@ -215,10 +215,11 @@ module Rel8

215215 , Aggregate

216216 , aggregate

217217 , countRows

218+ , groupBy

219+ , headAgg

218220 , array1DAggExpr

219221 , listAgg, listAggWithOrder, listAggExpr

220222 , nonEmptyAgg, nonEmptyAggWithOrder, nonEmptyAggExpr

221− , groupBy

222223 , DBMax, max

223224 , DBMin, min

224225 , DBSum, sum, sumWhere

src/Rel8/Aggregate/Legacy.hs+12−2

@@ -13,6 +13,7 @@ module Rel8.Aggregate.Legacy

1313 , aggregate

1414 , aggregateTabulation

1515 , groupBy

16+ , headAgg

1617 , listAgg

1718 , nonEmptyAgg

1819

@@ -33,14 +34,18 @@ import qualified Opaleye.Aggregate as Opaleye

3334-- rel8

3435import Rel8.Aggregate ( Aggregate, Aggregates, Col( A ) )

3536import Rel8.Expr ( Col( E ), Expr )

36−import Rel8.Expr.Aggregate ( groupByExpr, listAggExpr, nonEmptyAggExpr )

37+import Rel8.Expr.Aggregate

38+ ( groupByExpr

39+ , headAggExpr

40+ , listAggExpr, nonEmptyAggExpr

41+ )

3742import Rel8.Generic.Construction ( GGAggregate', ggaggregate' )

3843import Rel8.Generic.Table ( GAlgebra )

3944import Rel8.Kind.Algebra ( Algebra( Sum ) )

4045import Rel8.Query ( Query )

4146import Rel8.Query.Opaleye ( mapOpaleye )

4247import Rel8.Schema.Dict ( Dict( Dict ) )

43−import Rel8.Schema.HTable ( htabulate, hfield )

48+import Rel8.Schema.HTable ( hmap, hfield, htabulate )

4449import Rel8.Schema.HTable.Vectorize ( hvectorize )

4550import Rel8.Schema.Kind ( Rel8able )

4651import Rel8.Table ( toColumns, fromColumns )

@@ -76,6 +81,11 @@ groupBy (toColumns -> exprs) = fromColumns $ htabulate $ \field ->

7681 E expr -> A $ groupByExpr expr

7782

7883

84+-- | Keep only the first row's values.

85+headAgg :: Aggregates aggregates exprs => exprs -> aggregates

86+headAgg = fromColumns . hmap (\(E a) -> A $ headAggExpr a) . toColumns

87+

88+

7989-- | Aggregate rows into a single row containing an array of all aggregated

8090-- rows. This can be used to associate multiple rows with a single row, without

8191-- changing the over cardinality of the query. This allows you to essentially

src/Rel8/Expr/Aggregate.hs+15

@@ -12,6 +12,7 @@ module Rel8.Expr.Aggregate

1212 , sum, sumWhere

1313 , stringAgg

1414 , groupByExpr

15+ , headAggExpr

1516 , array1DAggExpr, listAggExpr, nonEmptyAggExpr

1617 , listAggExprWithOrder, nonEmptyAggExprWithOrder

1718 )

@@ -155,6 +156,20 @@ groupByExpr :: Sql DBEq a => Expr a -> Aggregate (Expr a)

155156groupByExpr = unsafeMakeAggregate toPrimExpr fromPrimExpr Nothing

156157

157158

159+-- | Keep only the first value.

160+headAggExpr :: Expr a -> Aggregate (Expr a)

161+headAggExpr = unsafeMakeAggregate toPrimExpr from $ Just

162+ Aggregator

163+ { operation = Opaleye.AggrArr

164+ , ordering = []

165+ , distinction = Opaleye.AggrAll

166+ }

167+ where

168+ from = fromPrimExpr . flip Opaleye.ArrayIndex one

169+ where

170+ one = Opaleye.ConstExpr (Opaleye.NumericLit 1)

171+

172+

158173-- | Collect expressions values as an array.

159174array1DAggExpr :: NotArray a => Expr a -> Aggregate (Expr (Array1D a))

160175array1DAggExpr = unsafeMakeAggregate toPrimExpr fromPrimExpr $ Just

src/Rel8/Table/Aggregate.hs+8−1

@@ -6,6 +6,7 @@

77module Rel8.Table.Aggregate

88 ( groupBy

9+ , headAgg

910 , listAgg, nonEmptyAgg

1011 , listAggWithOrder, nonEmptyAggWithOrder

1112 )

@@ -20,6 +21,7 @@ import Rel8.Aggregate ( Aggregate, Col( A ) )

2021import Rel8.Expr ( Expr, Col( E ) )

2122import Rel8.Expr.Aggregate

2223 ( groupByExpr

24+ , headAggExpr

2325 , listAggExpr

2426 , listAggExprWithOrder

2527 , nonEmptyAggExpr

@@ -27,7 +29,7 @@ import Rel8.Expr.Aggregate

2729 )

2830import Rel8.Order ( Order )

2931import Rel8.Schema.Dict ( Dict( Dict ) )

30−import Rel8.Schema.HTable ( htabulate, hfield )

32+import Rel8.Schema.HTable ( hfield, hmap, htabulate )

3133import Rel8.Schema.HTable.Vectorize ( hvectorize )

3234import Rel8.Table ( Table, toColumns, fromColumns )

3335import Rel8.Table.Eq ( EqTable, eqTable )

@@ -44,6 +46,11 @@ groupBy (toColumns -> exprs) = fromColumns $ htabulate $ \field ->

4446 E expr -> A $ groupByExpr expr

4547

4648

49+-- | Keep only the first row.

50+headAgg :: Table Expr a => a -> Aggregate a

51+headAgg = fromColumns . hmap (\(E a) -> A $ headAggExpr a) . toColumns

52+

53+

4754-- | Aggregate rows into a single row containing an array of all aggregated

4855-- rows. This can be used to associate multiple rows with a single row, without

4956-- changing the over cardinality of the query. This allows you to essentially