hasura · 0x777 · Nov 14, 2018 · Nov 13, 2018 · Nov 13, 2018 · Nov 13, 2018
@@ -154,7 +154,7 @@ parseOnConflict inpCols val = withPathK "on_conflict" $
   flip withObject val $ \_ obj -> do
     actionM <- forM (OMap.lookup "action" obj) parseAction
     constraint <- parseConstraint obj
-    updColsM <- forM (OMap.lookup "update_columns" obj) parseUpdCols
+    updColsM <- forM (OMap.lookup "update_columns" obj) parseColumns
     -- consider "action" if "update_columns" is not mentioned
     return $ mkConflictClause $ case (updColsM, actionM) of
       (Just [], _)             -> RI.CCDoNothing $ Just constraint
@@ -177,11 +177,6 @@ parseOnConflict inpCols val = withPathK "on_conflict" $
       (_, enumVal) <- asEnumVal v
       return $ ConstraintName $ G.unName $ G.unEnumValue enumVal
 
-    parseUpdCols v = flip withArray v $ \_ enumVals ->
-      forM enumVals $ \eVal -> do
-        (_, ev) <- asEnumVal eVal
-        return $ PGCol $ G.unName $ G.unEnumValue ev
-
     mkConflictClause (RI.CCDoNothing constrM) =
       RI.CP1DoNothing $ fmap RI.Constraint constrM
     mkConflictClause (RI.CCUpdate constr updCols) =

@@ -10,6 +10,7 @@ module Hasura.GraphQL.Resolve.Select
   ( convertSelect
   , convertSelectByPKey
   , convertAggSelect
+  , parseColumns
   , withSelSet
   , fromSelSet
   , fieldAsPath
@@ -32,6 +33,7 @@ import qualified Hasura.SQL.DML                    as S
 import           Hasura.GraphQL.Resolve.BoolExp
 import           Hasura.GraphQL.Resolve.Context
 import           Hasura.GraphQL.Resolve.InputValue
+import           Hasura.GraphQL.Schema             (isAggFld)
 import           Hasura.GraphQL.Validate.Field
 import           Hasura.GraphQL.Validate.Types
 import           Hasura.RQL.DML.Internal           (onlyPositiveInt)
@@ -199,6 +201,29 @@ convertSelectByPKey qt permFilter fld = do
   return $ RS.selectP2 True (selData, prepArgs)
 
 -- agg select related
+parseColumns :: MonadError QErr m => AnnGValue -> m [PGCol]
+parseColumns val =
+  flip withArray val $ \_ vals ->
+    forM vals $ \v -> do
+      (_, enumVal) <- asEnumVal v
+      return $ PGCol $ G.unName $ G.unEnumValue enumVal
+
+convertCount :: MonadError QErr m => ArgsMap -> m S.CountType
+convertCount args = do
+  columnsM <- withArgM args "columns" parseColumns
+  isDistinct <- or <$> withArgM args "distinct" parseDistinct
+  maybe (return S.CTStar) (mkCType isDistinct) columnsM
+  where
+    parseDistinct v = do
+      (_, val) <- asPGColVal v
+      case val of
+        PGValBoolean b -> return b
+        _              ->
+          throw500 "expecting Boolean for \"distinct\""
+
+    mkCType isDistinct cols = return $
+      bool (S.CTSimple cols) (S.CTDistinct cols) isDistinct
+
 convertColFlds
   :: Monad m => G.NamedType -> SelSet -> m RS.ColFlds
 convertColFlds ty selSet =
@@ -216,12 +241,14 @@ convertAggFld ty selSet =
         fSelSet = _fSelSet fld
     case _fName fld of
       "__typename" -> return $ RS.AFExp $ G.unName $ G.unNamedType ty
-      "count"      -> return RS.AFCount
-      "sum"        -> RS.AFSum <$> convertColFlds fType fSelSet
-      "avg"        -> RS.AFAvg <$> convertColFlds fType fSelSet
-      "max"        -> RS.AFMax <$> convertColFlds fType fSelSet
-      "min"        -> RS.AFMin <$> convertColFlds fType fSelSet
-      G.Name t     -> throw500 $ "unexpected field in _agg node: " <> t
+      "count"      -> RS.AFCount <$> convertCount (_fArguments fld)
+      n            -> do
+        colFlds <- convertColFlds fType fSelSet
+        unless (isAggFld n) $ throwInvalidFld n
+        return $ RS.AFOp $ RS.AggOp (G.unName n) colFlds
+  where
+      throwInvalidFld (G.Name t) =
+        throw500 $ "unexpected field in _aggregate node: " <> t
 
 fromAggField
   :: (MonadError QErr m, MonadReader r m, Has FieldMap r, Has OrdByCtx r)

@@ -17,6 +17,7 @@ module Hasura.GraphQL.Schema
   , InsCtx(..)
   , InsCtxMap
   , RelationInfoMap
+  , isAggFld
   ) where
 
 import           Data.Has
@@ -153,6 +154,17 @@ isRelNullable fim ri = isNullable
     lColInfos = getColInfos lCols allCols
     isNullable = any pgiIsNullable lColInfos
 
+numAggOps :: [G.Name]
+numAggOps = [ "sum", "avg", "stddev", "stddev_samp", "stddev_pop"
+            , "variance", "var_samp", "var_pop"
+            ]
+
+compAggOps :: [G.Name]
+compAggOps = ["max", "min"]
+
+isAggFld :: G.Name -> Bool
+isAggFld = flip elem (numAggOps <> compAggOps)
+
 mkColName :: PGCol -> G.Name
 mkColName (PGCol n) = G.Name n
 
@@ -378,7 +390,14 @@ mkTableAggObj tn =
 {-
 type table_aggregate_fields{
   count: Int
-  sum: table_num_fields
+  sum: table_sum_fields
+  avg: table_avg_fields
+  stddev: table_stddev_fields
+  stddev_pop: table_stddev_pop_fields
+  variance: table_variance_fields
+  var_pop: table_var_pop_fields
+  max: table_max_fields
+  min: table_min_fields
 }
 -}
 mkTableAggFldsObj
@@ -390,22 +409,24 @@ mkTableAggFldsObj tn numCols compCols =
     desc = G.Description $
       "aggregate fields of " <>> tn
 
-    countFld = ObjFldInfo Nothing "count" Map.empty $ G.toGT $
+    countFld = ObjFldInfo Nothing "count" countParams $ G.toGT $
                mkScalarTy PGInteger
 
-    numFlds = bool [sumFld, avgFld] [] $ null numCols
-    compFlds = bool [maxFld, minFld] [] $ null compCols
+    countParams = fromInpValL [countColInpVal, distinctInpVal]
 
-    sumFld = mkColOpFld "sum"
-    avgFld = mkColOpFld "avg"
-    maxFld = mkColOpFld "max"
-    minFld = mkColOpFld "min"
+    countColInpVal = InpValInfo Nothing "columns" $ G.toGT $
+                     G.toLT $ G.toNT $ mkSelColumnInpTy tn
+    distinctInpVal = InpValInfo Nothing "distinct" $ G.toGT $
+                     mkScalarTy PGBoolean
+
+    numFlds = bool (map mkColOpFld numAggOps) [] $ null numCols
+    compFlds = bool (map mkColOpFld compAggOps) [] $ null compCols
 
     mkColOpFld op = ObjFldInfo Nothing op Map.empty $ G.toGT $
                     mkTableColAggFldsTy op tn
 
 {-
-type table_sum_fields{
+type table_<agg-op>_fields{
    num_col: Int
    .        .
    .        .
@@ -840,10 +861,15 @@ mkConstraintInpTy :: QualifiedTable -> G.NamedType
 mkConstraintInpTy tn =
   G.NamedType $ qualTableToName tn <> "_constraint"
 
--- table_column
-mkColumnInpTy :: QualifiedTable -> G.NamedType
-mkColumnInpTy tn =
-  G.NamedType $ qualTableToName tn <> "_column"
+-- table_update_column
+mkUpdColumnInpTy :: QualifiedTable -> G.NamedType
+mkUpdColumnInpTy tn =
+  G.NamedType $ qualTableToName tn <> "_update_column"
+
+--table_select_column
+mkSelColumnInpTy :: QualifiedTable -> G.NamedType
+mkSelColumnInpTy tn =
+  G.NamedType $ qualTableToName tn <> "_select_column"
 {-
 input table_obj_rel_insert_input {
   data: table_insert_input!
@@ -946,7 +972,7 @@ mkOnConflictInp tn =
       G.toGT $ G.toNT $ mkConstraintInpTy tn
 
     updateColumnsInpVal = InpValInfo Nothing (G.Name "update_columns") $
-      G.toGT $ G.toLT $ G.toNT $ mkColumnInpTy tn
+      G.toGT $ G.toLT $ G.toNT $ mkUpdColumnInpTy tn
 {-
 
 insert_table(
@@ -991,17 +1017,27 @@ mkConstriantTy tn cons = enumTyInfo
       EnumValInfo (Just "unique or primary key constraint")
       (G.EnumValue $ G.Name n) False
 
-mkColumnTy :: QualifiedTable -> [PGCol] -> EnumTyInfo
-mkColumnTy tn cols = enumTyInfo
+mkColumnEnumVal :: PGCol -> EnumValInfo
+mkColumnEnumVal (PGCol col) =
+  EnumValInfo (Just "column name") (G.EnumValue $ G.Name col) False
+
+mkUpdColumnTy :: QualifiedTable -> [PGCol] -> EnumTyInfo
+mkUpdColumnTy tn cols = enumTyInfo
   where
-    enumTyInfo = EnumTyInfo (Just desc) (mkColumnInpTy tn) $
+    enumTyInfo = EnumTyInfo (Just desc) (mkUpdColumnInpTy tn) $
                  mapFromL _eviVal $ map mkColumnEnumVal cols
 
     desc = G.Description $
-      "columns of table " <>> tn
+      "update columns of table " <>> tn
 
-    mkColumnEnumVal (PGCol col) =
-      EnumValInfo (Just "column name") (G.EnumValue $ G.Name col) False
+mkSelColumnTy :: QualifiedTable -> [PGCol] -> EnumTyInfo
+mkSelColumnTy tn cols = enumTyInfo
+  where
+    enumTyInfo = EnumTyInfo (Just desc) (mkSelColumnInpTy tn) $
+                 mapFromL _eviVal $ map mkColumnEnumVal cols
+
+    desc = G.Description $
+      "select columns of table " <>> tn
 
 mkConflictActionTy :: EnumTyInfo
 mkConflictActionTy = EnumTyInfo (Just desc) ty $ mapFromL _eviVal
@@ -1108,7 +1144,7 @@ mkOnConflictTypes tn c cols =
   where
     tyInfos = [ TIEnum mkConflictActionTy
               , TIEnum $ mkConstriantTy tn constraints
-              , TIEnum $ mkColumnTy tn cols
+              , TIEnum $ mkUpdColumnTy tn cols
               , TIInpObj $ mkOnConflictInp tn
               ]
     constraints = filter isUniqueOrPrimary c
@@ -1159,6 +1195,7 @@ mkGCtxRole' tn insPermM selPermM updColsM delPermM pkeyCols constraints viM allC
       , TIInpObj <$> mutHelper viIsUpdatable updSetInpObjM
       , TIInpObj <$> mutHelper viIsUpdatable updIncInpObjM
       , TIObj <$> mutRespObjM
+      , TIEnum <$> selColInpTyM
       ]
     mutHelper f objM = bool Nothing objM $ isMutable f viM
 
@@ -1190,6 +1227,8 @@ mkGCtxRole' tn insPermM selPermM updColsM delPermM pkeyCols constraints viM allC
     updSetInpObjFldsM = mkColFldMap (mkUpdSetTy tn) <$> updColsM
 
     selFldsM = snd <$> selPermM
+    selColsM = (map pgiName . lefts) <$> selFldsM
+    selColInpTyM = mkSelColumnTy tn <$> selColsM
     -- boolexp input type
     boolExpInpObjM = case selFldsM of
       Just selFlds  -> Just $ mkBoolExpInp tn selFlds
@@ -1240,15 +1279,18 @@ mkGCtxRole' tn insPermM selPermM updColsM delPermM pkeyCols constraints viM allC
       _ -> []
     getNumCols = onlyNumCols . lefts
     getCompCols = onlyComparableCols . lefts
+    onlyFloat = const $ mkScalarTy PGFloat
+
+    mkTypeMaker "sum" = mkScalarTy
+    mkTypeMaker _     = onlyFloat
+
     mkColAggFldsObjs flds =
       let numCols = getNumCols flds
           compCols = getCompCols flds
-          sumFldsObj = mkTableColAggFldsObj tn "sum" mkScalarTy numCols
-          avgFldsObj = mkTableColAggFldsObj tn "avg" (const $ mkScalarTy PGFloat) numCols
-          maxFldsObj = mkTableColAggFldsObj tn "max" mkScalarTy compCols
-          minFldsObj = mkTableColAggFldsObj tn "min" mkScalarTy compCols
-          numFldsObjs = bool [sumFldsObj, avgFldsObj] [] $ null numCols
-          compFldsObjs = bool [maxFldsObj, minFldsObj] [] $ null compCols
+          mkNumObjFld n = mkTableColAggFldsObj tn n (mkTypeMaker n) numCols
+          mkCompObjFld n = mkTableColAggFldsObj tn n mkScalarTy compCols
+          numFldsObjs = bool (map mkNumObjFld numAggOps) [] $ null numCols
+          compFldsObjs = bool (map mkCompObjFld compAggOps) [] $ null compCols
       in numFldsObjs <> compFldsObjs
     -- the fields used in table object
     selObjFldsM = mkFldMap (mkTableTy tn) <$> selFldsM

@@ -41,7 +41,7 @@ mkSQLCount
   :: CountQueryP1 -> S.Select
 mkSQLCount (CountQueryP1 tn (permFltr, mWc) mDistCols) =
   S.mkSelect
-    { S.selExtr = [S.Extractor (S.SEFnApp "count" [S.SEStar] Nothing) Nothing]
+    { S.selExtr = [S.Extractor S.countStar Nothing]
     , S.selFrom = Just $ S.FromExp
                   [S.mkSelFromExp False innerSel $ TableName "r"]
     }

@@ -54,7 +54,7 @@ mkMutFldExp :: QualifiedTable -> Bool -> MutFld -> S.SQLExp
 mkMutFldExp qt singleObj = \case
   MCount -> S.SESelect $
     S.mkSelect
-    { S.selExtr = [S.Extractor (S.SEUnsafe "count(*)") Nothing]
+    { S.selExtr = [S.Extractor S.countStar Nothing]
     , S.selFrom = Just $ S.FromExp $ pure frmItem
     }
   MExp t -> S.SELit t

@@ -101,12 +101,15 @@ data PGColFld
 
 type ColFlds = [(T.Text, PGColFld)]
 
+data AggOp
+  = AggOp
+  { _aoOp   :: !T.Text
+  , _aoFlds :: !ColFlds
+  } deriving (Show, Eq)
+
 data AggFld
-  = AFCount
-  | AFSum !ColFlds
-  | AFAvg !ColFlds
-  | AFMax !ColFlds
-  | AFMin !ColFlds
+  = AFCount !S.CountType
+  | AFOp !AggOp
   | AFExp !T.Text
   deriving (Show, Eq)
 
@@ -165,14 +168,11 @@ aggFldToExp aggFlds = jsonRow
     jsonRow = S.applyJsonBuildObj (concatMap aggToFlds aggFlds)
     withAls fldName sqlExp = [S.SELit fldName, sqlExp]
     aggToFlds (t, fld) = withAls t $ case fld of
-      AFCount       -> S.SEUnsafe "count(*)"
-      AFSum sumFlds -> colFldsToObj "sum" sumFlds
-      AFAvg avgFlds -> colFldsToObj "avg" avgFlds
-      AFMax maxFlds -> colFldsToObj "max" maxFlds
-      AFMin minFlds -> colFldsToObj "min" minFlds
-      AFExp e       -> S.SELit e
-
-    colFldsToObj op flds =
+      AFCount cty -> S.SECount cty
+      AFOp aggOp  -> aggOpToObj aggOp
+      AFExp e     -> S.SELit e
+
+    aggOpToObj (AggOp op flds) =
       S.applyJsonBuildObj $ concatMap (colFldsToExtr op) flds
 
     colFldsToExtr op (t, PCFCol col) =
@@ -442,14 +442,17 @@ mkBaseNode pfx fldAls annSelFlds tableFrom tablePerm tableArgs =
            )
       TAFExp _ -> (HM.fromList obExtrs, HM.empty, HM.empty, HM.empty)
 
-    fetchExtrFromAggFld AFCount         = []
-    fetchExtrFromAggFld (AFSum sumFlds) = colFldsToExps sumFlds
-    fetchExtrFromAggFld (AFAvg avgFlds) = colFldsToExps avgFlds
-    fetchExtrFromAggFld (AFMax maxFlds) = colFldsToExps maxFlds
-    fetchExtrFromAggFld (AFMin minFlds) = colFldsToExps minFlds
-    fetchExtrFromAggFld (AFExp _)       = []
+    fetchExtrFromAggFld (AFCount cty) = countTyToExps cty
+    fetchExtrFromAggFld (AFOp aggOp)  = aggOpToExps aggOp
+    fetchExtrFromAggFld (AFExp _)     = []
+
+    countTyToExps S.CTStar            = []
+    countTyToExps (S.CTSimple cols)   = colsToExps cols
+    countTyToExps (S.CTDistinct cols) = colsToExps cols
+
+    colsToExps = mapMaybe (mkColExp . PCFCol)
 
-    colFldsToExps = mapMaybe (mkColExp . snd)
+    aggOpToExps = mapMaybe (mkColExp . snd) . _aoFlds
 
     mkColExp (PCFCol c) =
       let qualCol = S.mkQIdenExp (mkBaseTableAls pfx) (toIden c)