Fix enum default validation to use actual column names

- Move validateEnumLiteralDefault to resolve_column_defaults.go
- Pass actual column name instead of '(unknown)' to match MySQL
- MySQL returns 'Invalid default value for 'column_name'' format
- Remove enum validation from CheckType to avoid duplicate logic
- Verified behavior matches MySQL exactly for both invalid cases

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: elianddb

sql/analyzer/resolve_column_defaults.go

@@ -273,14 +273,52 @@ func validateColumnDefault(ctx *sql.Context, col *sql.Column, colDefault *sql.Co
 		return err
 	}
 
-	// validate type of default expression
-	if err = colDefault.CheckType(ctx); err != nil {
-		return err
+	// For enum literal defaults, use stricter validation than runtime conversion
+	if enumType, isEnum := col.Type.(sql.EnumType); isEnum && colDefault.IsLiteral() {
+		if err = validateEnumLiteralDefault(enumType, colDefault, col.Name, ctx); err != nil {
+			return err
+		}
+	} else {
+		// validate type of default expression
+		if err = colDefault.CheckType(ctx); err != nil {
+			return err
+		}
 	}
 
 	return nil
 }
 
+// validateEnumLiteralDefault validates enum literal defaults more strictly than runtime conversions
+// MySQL doesn't allow numeric index references for literal enum defaults
+func validateEnumLiteralDefault(enumType sql.EnumType, colDefault *sql.ColumnDefaultValue, columnName string, ctx *sql.Context) error {
+	val, err := colDefault.Expr.Eval(ctx, nil)
+	if err != nil {
+		return err
+	}
+
+	switch v := val.(type) {
+	case string:
+		// For string values, check if it's a direct enum value match
+		enumValues := enumType.Values()
+		for _, enumVal := range enumValues {
+			if enumVal == v {
+				return nil // Valid enum value
+			}
+		}
+		// String doesn't match any enum value, return appropriate error
+		if v == "" {
+			return sql.ErrIncompatibleDefaultType.New()
+		}
+		return sql.ErrInvalidColumnDefaultValue.New(columnName)
+	case int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64:
+		// MySQL doesn't allow numeric enum indices as literal defaults
+		return sql.ErrInvalidColumnDefaultValue.New(columnName)
+	default:
+		// Other types not supported for enum defaults
+		return sql.ErrIncompatibleDefaultType.New()
+	}
+}
+
 func stripTableNamesFromDefault(e *expression.Wrapper) (sql.Expression, transform.TreeIdentity, error) {
 	newDefault, ok := e.Unwrap().(*sql.ColumnDefaultValue)
 	if !ok {

sql/columndefault.go

@@ -227,12 +227,6 @@ func (e *ColumnDefaultValue) CheckType(ctx *Context) error {
 		if val == nil && !e.ReturnNil {
 			return ErrIncompatibleDefaultType.New()
 		}
-		
-		// For enum literal defaults, use stricter validation than runtime conversion
-		if enumType, isEnum := e.OutType.(EnumType); isEnum {
-			return e.validateEnumLiteralDefault(enumType, val)
-		}
-		
 		_, inRange, err := e.OutType.Convert(ctx, val)
 		if err != nil {
 			return ErrIncompatibleDefaultType.Wrap(err)
@@ -244,32 +238,6 @@ func (e *ColumnDefaultValue) CheckType(ctx *Context) error {
 	return nil
 }
 
-// validateEnumLiteralDefault validates enum literal defaults more strictly than runtime conversions
-// MySQL doesn't allow numeric index references for literal enum defaults
-func (e *ColumnDefaultValue) validateEnumLiteralDefault(enumType EnumType, val interface{}) error {
-	switch v := val.(type) {
-	case string:
-		// For string values, check if it's a direct enum value match
-		enumValues := enumType.Values()
-		for _, enumVal := range enumValues {
-			if enumVal == v {
-				return nil // Valid enum value
-			}
-		}
-		// String doesn't match any enum value, return appropriate error
-		if v == "" {
-			return ErrIncompatibleDefaultType.New()
-		}
-		return ErrInvalidColumnDefaultValue.New("(unknown)")
-	case int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64:
-		// MySQL doesn't allow numeric enum indices as literal defaults
-		return ErrInvalidColumnDefaultValue.New("(unknown)")
-	default:
-		// Other types not supported for enum defaults
-		return ErrIncompatibleDefaultType.New()
-	}
-}
-
 type UnresolvedColumnDefault struct {
 	ExprString string
 }