Do not rewrite the type description for CAST

go/test/endtoend/vtgate/misc_test.go

@@ -19,9 +19,10 @@ package vtgate
 import (
 	"context"
 	"fmt"
-	"github.com/google/go-cmp/cmp"
 	"testing"
 
+	"github.com/google/go-cmp/cmp"
+
 	"github.com/stretchr/testify/assert"
 
 	"github.com/stretchr/testify/require"
@@ -549,6 +550,14 @@ func TestShowColumns(t *testing.T) {
 	assertMatches(t, conn, "SHOW columns FROM `t5_null_vindex` in `ks`", expected)
 }
 
+func TestCastConvert(t *testing.T) {
+	conn, err := mysql.Connect(context.Background(), &vtParams)
+	require.NoError(t, err)
+	defer conn.Close()
+
+	assertMatches(t, conn, `SELECT CAST("test" AS CHAR(60))`, `[[VARCHAR("test")]]`)
+}
+
 func assertMatches(t *testing.T, conn *mysql.Conn, query, expected string) {
 	t.Helper()
 	qr := exec(t, conn, query)

go/vt/sqlparser/normalizer.go

@@ -73,6 +73,8 @@ func (nz *normalizer) WalkStatement(node SQLNode) (bool, error) {
 		// Common node types that never contain SQLVals or ListArgs but create a lot of object
 		// allocations.
 		return false, nil
+	case *ConvertType: // we should not rewrite the type description
+		return false, nil
 	}
 	return true, nil
 }
@@ -91,6 +93,9 @@ func (nz *normalizer) WalkSelect(node SQLNode) (bool, error) {
 	case OrderBy, GroupBy:
 		// do not make a bind var for order by column_position
 		return false, nil
+	case *ConvertType:
+		// we should not rewrite the type description
+		return false, nil
 	}
 	return true, nil
 }

go/vt/sqlparser/normalizer_test.go

@@ -195,6 +195,13 @@ func TestNormalize(t *testing.T) {
 		outbv: map[string]*querypb.BindVariable{
 			"bv1": sqltypes.TestBindVariable([]interface{}{1, []byte("2")}),
 		},
+	}, {
+		// Do not normalize cast/convert types
+		in:      `select CAST("test" AS CHAR(60))`,
+		outstmt: `select convert(:bv1, CHAR(60)) from dual`,
+		outbv: map[string]*querypb.BindVariable{
+			"bv1": sqltypes.StringBindVariable("test"),
+		},
 	}}
 	for _, tc := range testcases {
 		stmt, err := Parse(tc.in)