table, executor: set a real enum as the default enum value (#8469) (#…

…8476)

executor/write_test.go

@@ -1680,3 +1680,11 @@ func (s *testSuite) TestRebaseIfNeeded(c *C) {
 	tk.MustExec(`insert into t (b) values (6);`)
 	tk.MustQuery(`select a from t where b = 6;`).Check(testkit.Rows("30003"))
 }
+
+func (s *testSuite) TestDefEnumInsert(c *C) {
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec("use test")
+	tk.MustExec("create table test (id int, prescription_type enum('a','b','c','d','e','f') NOT NULL, primary key(id));")
+	tk.MustExec("insert into test (id)  values (1)")
+	tk.MustQuery("select prescription_type from test").Check(testkit.Rows("a"))
+}

table/column.go

@@ -341,7 +341,11 @@ func getColDefaultValueFromNil(ctx sessionctx.Context, col *model.ColumnInfo) (t
 	if col.Tp == mysql.TypeEnum {
 		// For enum type, if no default value and not null is set,
 		// the default value is the first element of the enum list
-		return types.NewDatum(col.FieldType.Elems[0]), nil
+		defEnum, err := types.ParseEnumValue(col.FieldType.Elems, 1)
+		if err != nil {
+			return types.Datum{}, err
+		}
+		return types.NewMysqlEnumDatum(defEnum), nil
 	}
 	if mysql.HasAutoIncrementFlag(col.Flag) {
 		// Auto increment column doesn't has default value and we should not return error.

table/column_test.go

@@ -301,7 +301,7 @@ func (t *testTableSuite) TestGetDefaultValue(c *C) {
 				},
 			},
 			false,
-			types.NewStringDatum("abc"),
+			types.NewMysqlEnumDatum(types.Enum{Name: "abc", Value: 1}),
 			nil,
 		},
 		{

types/datum.go

@@ -1724,6 +1724,12 @@ func NewMysqlBitDatum(b BinaryLiteral) (d Datum) {
 	return d
 }
 
+// NewMysqlEnumDatum creates a new MysqlEnum Datum for a Enum value.
+func NewMysqlEnumDatum(e Enum) (d Datum) {
+	d.SetMysqlEnum(e)
+	return d
+}
+
 // MakeDatums creates datum slice from interfaces.
 func MakeDatums(args ...interface{}) []Datum {
 	datums := make([]Datum, len(args))