rename

Author: wjhuang2016

expression/column.go

@@ -123,9 +123,9 @@ func (col *CorrelatedColumn) IsCorrelated() bool {
 	return true
 }
 
-// ReferTable implements Expression interface.
-func (col *CorrelatedColumn) ReferTable() bool {
-	return true
+// ConstItem implements Expression interface.
+func (col *CorrelatedColumn) ConstItem() bool {
+	return false
 }
 
 // Decorrelate implements Expression interface.
@@ -302,9 +302,9 @@ func (col *Column) IsCorrelated() bool {
 	return false
 }
 
-// ReferTable implements Expression interface.
-func (col *Column) ReferTable() bool {
-	return true
+// ConstItem implements Expression interface.
+func (col *Column) ConstItem() bool {
+	return false
 }
 
 // Decorrelate implements Expression interface.

expression/column_test.go

@@ -43,7 +43,7 @@ func (s *testEvaluatorSuite) TestColumn(c *C) {
 	c.Assert(corCol.Equal(nil, corCol), IsTrue)
 	c.Assert(corCol.Equal(nil, invalidCorCol), IsFalse)
 	c.Assert(corCol.IsCorrelated(), IsTrue)
-	c.Assert(corCol.ReferTable(), IsTrue)
+	c.Assert(corCol.ConstItem(), IsFalse)
 	c.Assert(corCol.Decorrelate(schema).Equal(nil, col), IsTrue)
 	c.Assert(invalidCorCol.Decorrelate(schema).Equal(nil, invalidCorCol), IsTrue)
 

expression/constant.go

@@ -311,9 +311,9 @@ func (c *Constant) IsCorrelated() bool {
 	return false
 }
 
-// ReferTable implements Expression interface.
-func (c *Constant) ReferTable() bool {
-	return false
+// ConstItem implements Expression interface.
+func (c *Constant) ConstItem() bool {
+	return true
 }
 
 // Decorrelate implements Expression interface.

expression/expression.go

@@ -79,8 +79,8 @@ type Expression interface {
 	// IsCorrelated checks if this expression has correlated key.
 	IsCorrelated() bool
 
-	// ReferTable checks if this expression refers to a table.
-	ReferTable() bool
+	// ConstItem checks if this expression refers to a table.
+	ConstItem() bool
 
 	// Decorrelate try to decorrelate the expression by schema.
 	Decorrelate(schema *Schema) Expression

expression/expression_test.go

@@ -61,7 +61,7 @@ func (s *testEvaluatorSuite) TestConstant(c *C) {
 
 	sc := &stmtctx.StatementContext{TimeZone: time.Local}
 	c.Assert(Zero.IsCorrelated(), IsFalse)
-	c.Assert(Zero.ReferTable(), IsFalse)
+	c.Assert(Zero.ConstItem(), IsTrue)
 	c.Assert(Zero.Decorrelate(nil).Equal(s.ctx, Zero), IsTrue)
 	c.Assert(Zero.HashCode(sc), DeepEquals, []byte{0x0, 0x8, 0x0})
 	c.Assert(Zero.Equal(s.ctx, One), IsFalse)
@@ -86,6 +86,19 @@ func (s *testEvaluatorSuite) TestIsBinaryLiteral(c *C) {
 	c.Assert(IsBinaryLiteral(con), IsFalse)
 }
 
+func (s *testEvaluatorSuite) TestConstItem(c *C) {
+	defer testleak.AfterTest(c)()
+
+	sf := newFunction(ast.Rand)
+	c.Assert(sf.ConstItem(), Equals, false)
+	sf = newFunction(ast.UUID)
+	c.Assert(sf.ConstItem(), Equals, false)
+	sf = newFunction(ast.GetParam, One)
+	c.Assert(sf.ConstItem(), Equals, false)
+	sf = newFunction(ast.Abs, One)
+	c.Assert(sf.ConstItem(), Equals, true)
+}
+
 type testTableBuilder struct {
 	tableName   string
 	columnNames []string

expression/scalar_function.go

@@ -165,14 +165,20 @@ func (sf *ScalarFunction) IsCorrelated() bool {
 	return false
 }
 
-// ReferTable implements Expression interface.
-func (sf *ScalarFunction) ReferTable() bool {
+// ConstItem implements Expression interface.
+func (sf *ScalarFunction) ConstItem() bool {
+	if _, ok := DeferredFunctions[sf.FuncName.L]; ok {
+		return false
+	}
+	if sf.FuncName.L == ast.GetParam {
+		return false
+	}
 	for _, arg := range sf.GetArgs() {
-		if arg.ReferTable() {
-			return true
+		if !arg.ConstItem() {
+			return false
 		}
 	}
-	return false
+	return true
 }
 
 // Decorrelate implements Expression interface.

expression/scalar_function_test.go

@@ -40,7 +40,7 @@ func (s *testEvaluatorSuite) TestScalarFunction(c *C) {
 	c.Assert(err, IsNil)
 	c.Assert(res, DeepEquals, []byte{0x22, 0x6c, 0x74, 0x28, 0x66, 0x65, 0x69, 0x2e, 0x68, 0x61, 0x6e, 0x2c, 0x20, 0x31, 0x29, 0x22})
 	c.Assert(sf.IsCorrelated(), IsFalse)
-	c.Assert(sf.ReferTable(), IsTrue)
+	c.Assert(sf.ConstItem(), IsFalse)
 	c.Assert(sf.Decorrelate(nil).Equal(s.ctx, sf), IsTrue)
 	c.Assert(sf.HashCode(sc), DeepEquals, []byte{0x3, 0x4, 0x6c, 0x74, 0x1, 0x80, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x1, 0x0, 0x5, 0xbf, 0xf0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0})