expression: disable some json function from pushdown to TiFlash (#56177…

…) (#59205) close #56173
pingcap · Jan 26, 2025 · fe3f3c8 · fe3f3c8
1 parent 232d350
commit fe3f3c8
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Showing 2 changed files with 91 additions and 11 deletions.
diff --git a/expression/expr_to_pb_test.go b/expression/expr_to_pb_test.go
@@ -503,13 +503,93 @@ func TestOtherFunc2Pb(t *testing.T) {
 	}
 }
 
-func TestExprPushDownToFlash(t *testing.T) {
+func TestJsonPushDownToFlash(t *testing.T) {
 	sc := new(stmtctx.StatementContext)
 	client := new(mock.Client)
 
 	exprs := make([]Expression, 0)
 
 	jsonColumn := genColumn(mysql.TypeJSON, 1)
+	intColumn := genColumn(mysql.TypeLonglong, 2)
+
+	// functions can be pushdown to tiflash
+	// json_length
+	function, err := NewFunction(mock.NewContext(), ast.JSONLength, types.NewFieldType(mysql.TypeLonglong), jsonColumn)
+	require.NoError(t, err)
+	exprs = append(exprs, function)
+
+	// IfNullJson
+	function, err = NewFunction(mock.NewContext(), ast.Ifnull, types.NewFieldType(mysql.TypeJSON), jsonColumn, jsonColumn)
+	require.NoError(t, err)
+	exprs = append(exprs, function)
+
+	// IfJson
+	function, err = NewFunction(mock.NewContext(), ast.If, types.NewFieldType(mysql.TypeJSON), intColumn, jsonColumn, jsonColumn)
+	require.NoError(t, err)
+	exprs = append(exprs, function)
+
+	// CaseWhenJson
+	function, err = NewFunction(mock.NewContext(), ast.Case, types.NewFieldType(mysql.TypeJSON), intColumn, jsonColumn, intColumn, jsonColumn, jsonColumn)
+	require.NoError(t, err)
+	exprs = append(exprs, function)
+
+	// CoalesceJson
+	function, err = NewFunction(mock.NewContext(), ast.Coalesce, types.NewFieldType(mysql.TypeJSON), jsonColumn, jsonColumn, jsonColumn)
+	require.NoError(t, err)
+	exprs = append(exprs, function)
+
+	pushed, remained := PushDownExprs(sc, exprs, client, kv.TiFlash)
+	require.Len(t, pushed, len(exprs))
+	require.Len(t, remained, 0)
+
+	// functions can not pushdown to tiflash
+	exprs = exprs[:0]
+	// LTJson
+	function, err = NewFunction(mock.NewContext(), ast.LT, types.NewFieldType(mysql.TypeLonglong), jsonColumn, jsonColumn)
+	require.NoError(t, err)
+	exprs = append(exprs, function)
+
+	// LEJson
+	function, err = NewFunction(mock.NewContext(), ast.LE, types.NewFieldType(mysql.TypeLonglong), jsonColumn, jsonColumn)
+	require.NoError(t, err)
+	exprs = append(exprs, function)
+
+	// GTJson
+	function, err = NewFunction(mock.NewContext(), ast.GT, types.NewFieldType(mysql.TypeLonglong), jsonColumn, jsonColumn)
+	require.NoError(t, err)
+	exprs = append(exprs, function)
+
+	// GEJson
+	function, err = NewFunction(mock.NewContext(), ast.GE, types.NewFieldType(mysql.TypeLonglong), jsonColumn, jsonColumn)
+	require.NoError(t, err)
+	exprs = append(exprs, function)
+
+	// EQJson
+	function, err = NewFunction(mock.NewContext(), ast.EQ, types.NewFieldType(mysql.TypeLonglong), jsonColumn, jsonColumn)
+	require.NoError(t, err)
+	exprs = append(exprs, function)
+
+	// NEJson
+	function, err = NewFunction(mock.NewContext(), ast.NE, types.NewFieldType(mysql.TypeLonglong), jsonColumn, jsonColumn)
+	require.NoError(t, err)
+	exprs = append(exprs, function)
+
+	// InJson
+	function, err = NewFunction(mock.NewContext(), ast.In, types.NewFieldType(mysql.TypeLonglong), jsonColumn, jsonColumn, jsonColumn)
+	require.NoError(t, err)
+	exprs = append(exprs, function)
+
+	pushed, remained = PushDownExprs(sc, exprs, client, kv.TiFlash)
+	require.Len(t, pushed, 0)
+	require.Len(t, remained, len(exprs))
+}
+
+func TestExprPushDownToFlash(t *testing.T) {
+	sc := new(stmtctx.StatementContext)
+	client := new(mock.Client)
+
+	exprs := make([]Expression, 0)
+
 	intColumn := genColumn(mysql.TypeLonglong, 2)
 	realColumn := genColumn(mysql.TypeDouble, 3)
 	decimalColumn := genColumn(mysql.TypeNewDecimal, 4)
@@ -521,12 +601,8 @@ func TestExprPushDownToFlash(t *testing.T) {
 	float32Column := genColumn(mysql.TypeFloat, 9)
 	enumColumn := genColumn(mysql.TypeEnum, 10)
 
-	function, err := NewFunction(mock.NewContext(), ast.JSONLength, types.NewFieldType(mysql.TypeLonglong), jsonColumn)
-	require.NoError(t, err)
-	exprs = append(exprs, function)
-
 	// lpad
-	function, err = NewFunction(mock.NewContext(), ast.Lpad, types.NewFieldType(mysql.TypeString), stringColumn, int32Column, stringColumn)
+	function, err := NewFunction(mock.NewContext(), ast.Lpad, types.NewFieldType(mysql.TypeString), stringColumn, int32Column, stringColumn)
 	require.NoError(t, err)
 	exprs = append(exprs, function)
 
@@ -948,10 +1024,6 @@ func TestExprPushDownToFlash(t *testing.T) {
 	require.NoError(t, err)
 	exprs = append(exprs, function)
 
-	function, err = NewFunction(mock.NewContext(), ast.JSONDepth, types.NewFieldType(mysql.TypeLonglong), jsonColumn)
-	require.NoError(t, err)
-	exprs = append(exprs, function)
-
 	// ExtractDatetimeFromString: can not be pushed
 	function, err = NewFunction(mock.NewContext(), ast.Extract, types.NewFieldType(mysql.TypeLonglong), stringColumn, stringColumn)
 	require.NoError(t, err)

diff --git a/expression/expression.go b/expression/expression.go
@@ -1072,7 +1072,15 @@ func scalarExprSupportedByFlash(function *ScalarFunction) bool {
 			tipb.ScalarFuncSig_CoalesceDuration,
 			tipb.ScalarFuncSig_IfNullDuration,
 			tipb.ScalarFuncSig_IfDuration,
-			tipb.ScalarFuncSig_CaseWhenDuration:
+			tipb.ScalarFuncSig_CaseWhenDuration,
+			tipb.ScalarFuncSig_LTJson,
+			tipb.ScalarFuncSig_LEJson,
+			tipb.ScalarFuncSig_GTJson,
+			tipb.ScalarFuncSig_GEJson,
+			tipb.ScalarFuncSig_EQJson,
+			tipb.ScalarFuncSig_NEJson,
+			tipb.ScalarFuncSig_JsonIsNull,
+			tipb.ScalarFuncSig_InJson:
 			return false
 		}
 		return true