insert: fix the auto id retry won't cast the datum to origin type (pi…

…ngcap#29997) (pingcap#30019)

executor/insert_common.go

@@ -756,7 +756,10 @@ func (e *InsertValues) adjustAutoIncrementDatum(ctx context.Context, d types.Dat
 	if retryInfo.Retrying {
 		id, ok := retryInfo.GetCurrAutoIncrementID()
 		if ok {
-			d.SetAutoID(id, c.Flag)
+			err := setDatumAutoIDAndCast(e.ctx, &d, id, c)
+			if err != nil {
+				return types.Datum{}, err
+			}
 			return d, nil
 		}
 	}
@@ -829,7 +832,10 @@ func (e *InsertValues) adjustAutoRandomDatum(ctx context.Context, d types.Datum,
 	if retryInfo.Retrying {
 		autoRandomID, ok := retryInfo.GetCurrAutoRandomID()
 		if ok {
-			d.SetAutoID(autoRandomID, c.Flag)
+			err := setDatumAutoIDAndCast(e.ctx, &d, autoRandomID, c)
+			if err != nil {
+				return types.Datum{}, err
+			}
 			return d, nil
 		}
 	}
@@ -855,7 +861,10 @@ func (e *InsertValues) adjustAutoRandomDatum(ctx context.Context, d types.Datum,
 			return types.Datum{}, err
 		}
 		e.ctx.GetSessionVars().StmtCtx.InsertID = uint64(recordID)
-		d.SetAutoID(recordID, c.Flag)
+		err = setDatumAutoIDAndCast(e.ctx, &d, recordID, c)
+		if err != nil {
+			return types.Datum{}, err
+		}
 		retryInfo.AddAutoRandomID(recordID)
 		return d, nil
 	}

executor/insert_test.go

@@ -1326,3 +1326,33 @@ func (s *testSuite9) TestIssue26762(c *C) {
 	_, err = tk.Exec("insert into t1 values('2020-02-31');")
 	c.Assert(err.Error(), Equals, `[table:1366]Incorrect date value: '2020-02-31' for column 'c1' at row 1`)
 }
+
+// TestInsertIssue29892 test the double type with auto_increment problem, just leverage the serial test suite.
+func (s *testAutoRandomSuite) TestInsertIssue29892(c *C) {
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec(`use test`)
+
+	tk.MustExec("set global tidb_txn_mode='optimistic';")
+	tk.MustExec("set global tidb_disable_txn_auto_retry=false;")
+	tk.MustExec("drop table if exists t")
+	tk.MustExec("create table t(a double auto_increment key, b int)")
+	tk.MustExec("insert into t values (146576794, 1)")
+
+	tk1 := testkit.NewTestKit(c, s.store)
+	tk1.MustExec(`use test`)
+	tk1.MustExec("begin")
+	tk1.MustExec("insert into t(b) select 1")
+
+	tk2 := testkit.NewTestKit(c, s.store)
+	tk2.MustExec(`use test`)
+	tk2.MustExec("begin")
+	tk2.MustExec("insert into t values (146576795, 1)")
+	tk2.MustExec("insert into t values (146576796, 1)")
+	tk2.MustExec("commit")
+
+	// since the origin auto-id (146576795) is cached in retryInfo, it will be fetched again to do the retry again,
+	// which will duplicate with what has been inserted in tk1.
+	_, err := tk1.Exec("commit")
+	c.Assert(err, NotNil)
+	c.Assert(strings.Contains(err.Error(), "Write conflict"), Equals, true)
+}

types/datum.go

@@ -365,6 +365,7 @@ func (d *Datum) GetRaw() []byte {
 }
 
 // SetAutoID set the auto increment ID according to its int flag.
+// Don't use it directly, useless wrapped with setDatumAutoIDAndCast.
 func (d *Datum) SetAutoID(id int64, flag uint) {
 	if mysql.HasUnsignedFlag(flag) {
 		d.SetUint64(uint64(id))