*: disable insert null to not-null column for single-row insertion in non-strict mode | tidb-test=pr/2410

pkg/ddl/reorg.go

@@ -112,8 +112,9 @@ func reorgTypeFlagsWithSQLMode(mode mysql.SQLMode) types.Flags {
 
 func reorgErrLevelsWithSQLMode(mode mysql.SQLMode) errctx.LevelMap {
 	return errctx.LevelMap{
-		errctx.ErrGroupTruncate: errctx.ResolveErrLevel(false, !mode.HasStrictMode()),
-		errctx.ErrGroupBadNull:  errctx.ResolveErrLevel(false, !mode.HasStrictMode()),
+		errctx.ErrGroupTruncate:  errctx.ResolveErrLevel(false, !mode.HasStrictMode()),
+		errctx.ErrGroupBadNull:   errctx.ResolveErrLevel(false, !mode.HasStrictMode()),
+		errctx.ErrGroupNoDefault: errctx.ResolveErrLevel(false, !mode.HasStrictMode()),
 		errctx.ErrGroupDividedByZero: errctx.ResolveErrLevel(
 			!mode.HasErrorForDivisionByZeroMode(),
 			!mode.HasStrictMode(),

pkg/errctx/context.go

@@ -187,6 +187,8 @@ const (
 	ErrGroupDupKey
 	// ErrGroupBadNull is the group of bad null errors
 	ErrGroupBadNull
+	// ErrGroupNoDefault is the group of no default value errors
+	ErrGroupNoDefault
 	// ErrGroupDividedByZero is the group of divided by zero errors
 	ErrGroupDividedByZero
 	// ErrGroupAutoIncReadFailed is the group of auto increment read failed errors
@@ -214,6 +216,8 @@ func init() {
 		ErrGroupBadNull: {
 			errno.ErrBadNull,
 			errno.ErrWarnNullToNotnull,
+		},
+		ErrGroupNoDefault: {
 			errno.ErrNoDefaultForField,
 		},
 		ErrGroupDividedByZero: {

pkg/executor/BUILD.bazel

@@ -432,6 +432,7 @@ go_test(
         "//pkg/store/helper",
         "//pkg/store/mockstore",
         "//pkg/store/mockstore/unistore",
+        "//pkg/table",
         "//pkg/table/tables",
         "//pkg/tablecodec",
         "//pkg/testkit",

pkg/executor/executor.go

@@ -1967,7 +1967,11 @@ func ResetContextOfStmt(ctx sessionctx.Context, s ast.StmtNode) (err error) {
 			errLevels[errctx.ErrGroupAutoIncReadFailed] = errctx.LevelWarn
 			errLevels[errctx.ErrGroupNoMatchedPartition] = errctx.LevelWarn
 		}
-		errLevels[errctx.ErrGroupBadNull] = errctx.ResolveErrLevel(false, !strictSQLMode || stmt.IgnoreErr)
+		// For single-row INSERT statements, ignore non-strict mode
+		// See https://dev.mysql.com/doc/refman/5.7/en/constraint-invalid-data.html
+		isSingleInsert := len(stmt.Lists) == 1
+		errLevels[errctx.ErrGroupBadNull] = errctx.ResolveErrLevel(false, (!strictSQLMode && !isSingleInsert) || stmt.IgnoreErr)
+		errLevels[errctx.ErrGroupNoDefault] = errctx.ResolveErrLevel(false, !strictSQLMode || stmt.IgnoreErr)
 		errLevels[errctx.ErrGroupDividedByZero] = errctx.ResolveErrLevel(
 			!vars.SQLMode.HasErrorForDivisionByZeroMode(),
 			!strictSQLMode || stmt.IgnoreErr,
@@ -2112,6 +2116,7 @@ func ResetUpdateStmtCtx(sc *stmtctx.StatementContext, stmt *ast.UpdateStmt, vars
 	errLevels := sc.ErrLevels()
 	errLevels[errctx.ErrGroupDupKey] = errctx.ResolveErrLevel(false, stmt.IgnoreErr)
 	errLevels[errctx.ErrGroupBadNull] = errctx.ResolveErrLevel(false, !strictSQLMode || stmt.IgnoreErr)
+	errLevels[errctx.ErrGroupNoDefault] = errLevels[errctx.ErrGroupBadNull]
 	errLevels[errctx.ErrGroupDividedByZero] = errctx.ResolveErrLevel(
 		!vars.SQLMode.HasErrorForDivisionByZeroMode(),
 		!strictSQLMode || stmt.IgnoreErr,
@@ -2133,6 +2138,7 @@ func ResetDeleteStmtCtx(sc *stmtctx.StatementContext, stmt *ast.DeleteStmt, vars
 	errLevels := sc.ErrLevels()
 	errLevels[errctx.ErrGroupDupKey] = errctx.ResolveErrLevel(false, stmt.IgnoreErr)
 	errLevels[errctx.ErrGroupBadNull] = errctx.ResolveErrLevel(false, !strictSQLMode || stmt.IgnoreErr)
+	errLevels[errctx.ErrGroupNoDefault] = errLevels[errctx.ErrGroupBadNull]
 	errLevels[errctx.ErrGroupDividedByZero] = errctx.ResolveErrLevel(
 		!vars.SQLMode.HasErrorForDivisionByZeroMode(),
 		!strictSQLMode || stmt.IgnoreErr,

pkg/executor/executor_pkg_test.go

@@ -346,6 +346,7 @@ func TestErrLevelsForResetStmtContext(t *testing.T) {
 				l[errctx.ErrGroupTruncate] = errctx.LevelError
 				l[errctx.ErrGroupDupKey] = errctx.LevelError
 				l[errctx.ErrGroupBadNull] = errctx.LevelError
+				l[errctx.ErrGroupNoDefault] = errctx.LevelError
 				l[errctx.ErrGroupDividedByZero] = errctx.LevelError
 				l[errctx.ErrGroupAutoIncReadFailed] = errctx.LevelError
 				l[errctx.ErrGroupNoMatchedPartition] = errctx.LevelError
@@ -360,6 +361,7 @@ func TestErrLevelsForResetStmtContext(t *testing.T) {
 				l[errctx.ErrGroupTruncate] = errctx.LevelWarn
 				l[errctx.ErrGroupDupKey] = errctx.LevelError
 				l[errctx.ErrGroupBadNull] = errctx.LevelWarn
+				l[errctx.ErrGroupNoDefault] = errctx.LevelWarn
 				l[errctx.ErrGroupDividedByZero] = errctx.LevelWarn
 				l[errctx.ErrGroupAutoIncReadFailed] = errctx.LevelError
 				l[errctx.ErrGroupNoMatchedPartition] = errctx.LevelError
@@ -374,6 +376,7 @@ func TestErrLevelsForResetStmtContext(t *testing.T) {
 				l[errctx.ErrGroupTruncate] = errctx.LevelWarn
 				l[errctx.ErrGroupDupKey] = errctx.LevelWarn
 				l[errctx.ErrGroupBadNull] = errctx.LevelWarn
+				l[errctx.ErrGroupNoDefault] = errctx.LevelWarn
 				l[errctx.ErrGroupDividedByZero] = errctx.LevelWarn
 				l[errctx.ErrGroupAutoIncReadFailed] = errctx.LevelWarn
 				l[errctx.ErrGroupNoMatchedPartition] = errctx.LevelWarn
@@ -388,6 +391,7 @@ func TestErrLevelsForResetStmtContext(t *testing.T) {
 				l[errctx.ErrGroupTruncate] = errctx.LevelWarn
 				l[errctx.ErrGroupDupKey] = errctx.LevelWarn
 				l[errctx.ErrGroupBadNull] = errctx.LevelWarn
+				l[errctx.ErrGroupNoDefault] = errctx.LevelWarn
 				l[errctx.ErrGroupDividedByZero] = errctx.LevelWarn
 				l[errctx.ErrGroupAutoIncReadFailed] = errctx.LevelError
 				l[errctx.ErrGroupNoMatchedPartition] = errctx.LevelWarn
@@ -402,6 +406,7 @@ func TestErrLevelsForResetStmtContext(t *testing.T) {
 				l[errctx.ErrGroupTruncate] = errctx.LevelWarn
 				l[errctx.ErrGroupDupKey] = errctx.LevelWarn
 				l[errctx.ErrGroupBadNull] = errctx.LevelWarn
+				l[errctx.ErrGroupNoDefault] = errctx.LevelWarn
 				l[errctx.ErrGroupDividedByZero] = errctx.LevelWarn
 				l[errctx.ErrGroupAutoIncReadFailed] = errctx.LevelError
 				l[errctx.ErrGroupNoMatchedPartition] = errctx.LevelError
@@ -416,6 +421,7 @@ func TestErrLevelsForResetStmtContext(t *testing.T) {
 				l[errctx.ErrGroupTruncate] = errctx.LevelError
 				l[errctx.ErrGroupDupKey] = errctx.LevelError
 				l[errctx.ErrGroupBadNull] = errctx.LevelError
+				l[errctx.ErrGroupNoDefault] = errctx.LevelError
 				l[errctx.ErrGroupDividedByZero] = errctx.LevelIgnore
 				l[errctx.ErrGroupAutoIncReadFailed] = errctx.LevelError
 				l[errctx.ErrGroupNoMatchedPartition] = errctx.LevelError
@@ -430,6 +436,7 @@ func TestErrLevelsForResetStmtContext(t *testing.T) {
 				l[errctx.ErrGroupTruncate] = errctx.LevelWarn
 				l[errctx.ErrGroupDupKey] = errctx.LevelError
 				l[errctx.ErrGroupBadNull] = errctx.LevelError
+				l[errctx.ErrGroupNoDefault] = errctx.LevelError
 				l[errctx.ErrGroupDividedByZero] = errctx.LevelWarn
 				l[errctx.ErrGroupAutoIncReadFailed] = errctx.LevelError
 				l[errctx.ErrGroupNoMatchedPartition] = errctx.LevelError
@@ -444,6 +451,7 @@ func TestErrLevelsForResetStmtContext(t *testing.T) {
 				l[errctx.ErrGroupTruncate] = errctx.LevelWarn
 				l[errctx.ErrGroupDupKey] = errctx.LevelError
 				l[errctx.ErrGroupBadNull] = errctx.LevelError
+				l[errctx.ErrGroupNoDefault] = errctx.LevelError
 				l[errctx.ErrGroupDividedByZero] = errctx.LevelWarn
 				l[errctx.ErrGroupAutoIncReadFailed] = errctx.LevelError
 				l[errctx.ErrGroupNoMatchedPartition] = errctx.LevelError
@@ -458,6 +466,7 @@ func TestErrLevelsForResetStmtContext(t *testing.T) {
 				l[errctx.ErrGroupTruncate] = errctx.LevelError
 				l[errctx.ErrGroupDupKey] = errctx.LevelError
 				l[errctx.ErrGroupBadNull] = errctx.LevelError
+				l[errctx.ErrGroupNoDefault] = errctx.LevelError
 				l[errctx.ErrGroupDividedByZero] = errctx.LevelWarn
 				l[errctx.ErrGroupAutoIncReadFailed] = errctx.LevelError
 				l[errctx.ErrGroupNoMatchedPartition] = errctx.LevelWarn
@@ -472,6 +481,7 @@ func TestErrLevelsForResetStmtContext(t *testing.T) {
 				l[errctx.ErrGroupTruncate] = errctx.LevelError
 				l[errctx.ErrGroupDupKey] = errctx.LevelError
 				l[errctx.ErrGroupBadNull] = errctx.LevelError
+				l[errctx.ErrGroupNoDefault] = errctx.LevelError
 				l[errctx.ErrGroupDividedByZero] = errctx.LevelWarn
 				l[errctx.ErrGroupAutoIncReadFailed] = errctx.LevelError
 				l[errctx.ErrGroupNoMatchedPartition] = errctx.LevelWarn

pkg/executor/insert_test.go

@@ -24,6 +24,7 @@ import (
 	"github.com/pingcap/tidb/pkg/executor"
 	"github.com/pingcap/tidb/pkg/meta/autoid"
 	"github.com/pingcap/tidb/pkg/sessionctx/variable"
+	"github.com/pingcap/tidb/pkg/table"
 	"github.com/pingcap/tidb/pkg/testkit"
 	"github.com/pingcap/tidb/pkg/util"
 	"github.com/pingcap/tidb/pkg/util/execdetails"
@@ -592,3 +593,30 @@ func TestInsertLockUnchangedKeys(t *testing.T) {
 		}
 	}
 }
+
+func TestInsertNullInNonStrictMode(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+	tk.MustExec("create table t1 (id int primary key, col1 varchar(10) not null default '')")
+	tk.MustExec("create table t2 (id int primary key, col1 varchar(10))")
+	tk.MustExec("insert into t2 values (1, null)")
+	tk.MustExec("insert ignore into t1 values(5, null)")
+
+	tk.MustExec("set session sql_mode = ''")
+
+	err := tk.ExecToErr("insert into t1 values(1, null)")
+	require.EqualError(t, err, table.ErrColumnCantNull.GenWithStackByArgs("col1").Error())
+
+	err = tk.ExecToErr("insert into t1 set id = 1, col1 = null")
+	require.EqualError(t, err, table.ErrColumnCantNull.GenWithStackByArgs("col1").Error())
+
+	err = tk.ExecToErr("insert t1 VALUES (5, 5) ON DUPLICATE KEY UPDATE col1 = null")
+	require.EqualError(t, err, table.ErrColumnCantNull.GenWithStackByArgs("col1").Error())
+
+	tk.MustExec("insert into t1 select * from t2")
+	tk.MustExec("insert into t1 values(2, null), (3, 3), (4, 4)")
+	tk.MustExec("update t1 set col1 = null where id = 3")
+	tk.MustExec("insert ignore t1 VALUES (4, 4) ON DUPLICATE KEY UPDATE col1 = null")
+	tk.MustQuery("select * from t1").Check(testkit.RowsWithSep("|", "1|", "2|", "3|", "4|", "5|"))
+}

pkg/executor/load_data.go

@@ -153,6 +153,7 @@ func setNonRestrictiveFlags(stmtCtx *stmtctx.StatementContext) {
 	levels := stmtCtx.ErrLevels()
 	levels[errctx.ErrGroupDupKey] = errctx.LevelWarn
 	levels[errctx.ErrGroupBadNull] = errctx.LevelWarn
+	levels[errctx.ErrGroupNoDefault] = errctx.LevelWarn
 	stmtCtx.SetErrLevels(levels)
 	stmtCtx.SetTypeFlags(stmtCtx.TypeFlags().WithTruncateAsWarning(true))
 }

pkg/executor/test/writetest/write_test.go

@@ -240,6 +240,7 @@ func TestIssue18681(t *testing.T) {
 	levels := ctx.GetSessionVars().StmtCtx.ErrLevels()
 	levels[errctx.ErrGroupDupKey] = errctx.LevelWarn
 	levels[errctx.ErrGroupBadNull] = errctx.LevelWarn
+	levels[errctx.ErrGroupNoDefault] = errctx.LevelWarn
 
 	sc := ctx.GetSessionVars().StmtCtx
 	oldTypeFlags := sc.TypeFlags()

pkg/expression/builtin_miscellaneous_vec_test.go

@@ -154,6 +154,7 @@ func TestSleepVectorized(t *testing.T) {
 	// non-strict model
 	var levels errctx.LevelMap
 	levels[errctx.ErrGroupBadNull] = errctx.LevelWarn
+	levels[errctx.ErrGroupNoDefault] = errctx.LevelWarn
 	sessVars.StmtCtx.SetErrLevels(levels)
 	input.AppendFloat64(0, 1)
 	err = vecEvalType(ctx, f, types.ETInt, input, result)
@@ -188,6 +189,7 @@ func TestSleepVectorized(t *testing.T) {
 
 	// for error case under the strict model
 	levels[errctx.ErrGroupBadNull] = errctx.LevelError
+	levels[errctx.ErrGroupNoDefault] = errctx.LevelError
 	sessVars.StmtCtx.SetErrLevels(levels)
 	input.Reset()
 	input.AppendNull(0)

pkg/expression/contextsession/sessionctx_test.go

@@ -54,7 +54,11 @@ func TestSessionEvalContextBasic(t *testing.T) {
 	ctx.ResetSessionAndStmtTimeZone(time.FixedZone("UTC+11", 11*3600))
 	vars.SQLMode = mysql.ModeStrictTransTables | mysql.ModeNoZeroDate
 	sc.SetTypeFlags(types.FlagIgnoreInvalidDateErr | types.FlagSkipUTF8Check)
-	sc.SetErrLevels(errctx.LevelMap{errctx.ErrGroupDupKey: errctx.LevelWarn, errctx.ErrGroupBadNull: errctx.LevelIgnore})
+	sc.SetErrLevels(errctx.LevelMap{
+		errctx.ErrGroupDupKey:    errctx.LevelWarn,
+		errctx.ErrGroupBadNull:   errctx.LevelIgnore,
+		errctx.ErrGroupNoDefault: errctx.LevelIgnore,
+	})
 	vars.CurrentDB = "db1"
 	vars.MaxAllowedPacket = 123456
 

pkg/expression/contextstatic/evalctx_test.go

@@ -110,6 +110,7 @@ func getEvalCtxOptionsForTest(t *testing.T) ([]StaticEvalCtxOption, *evalCtxOpti
 		WithTypeFlags(types.FlagAllowNegativeToUnsigned | types.FlagSkipASCIICheck),
 		WithErrLevelMap(errctx.LevelMap{
 			errctx.ErrGroupBadNull:       errctx.LevelError,
+			errctx.ErrGroupNoDefault:     errctx.LevelError,
 			errctx.ErrGroupDividedByZero: errctx.LevelWarn,
 		}),
 		WithLocation(loc),
@@ -143,6 +144,7 @@ func checkOptionsStaticEvalCtx(t *testing.T, ctx *StaticEvalContext, s *evalCtxO
 	)
 	require.Equal(t, errctx.NewContextWithLevels(errctx.LevelMap{
 		errctx.ErrGroupBadNull:       errctx.LevelError,
+		errctx.ErrGroupNoDefault:     errctx.LevelError,
 		errctx.ErrGroupDividedByZero: errctx.LevelWarn,
 	}, ctx), ctx.ErrCtx())
 	require.Same(t, s.loc, ctx.Location())

pkg/expression/evaluator_test.go

@@ -109,6 +109,7 @@ func TestSleep(t *testing.T) {
 	// non-strict model
 	var levels errctx.LevelMap
 	levels[errctx.ErrGroupBadNull] = errctx.LevelWarn
+	levels[errctx.ErrGroupNoDefault] = errctx.LevelWarn
 	sessVars.StmtCtx.SetErrLevels(levels)
 	d := make([]types.Datum, 1)
 	f, err := fc.getFunction(ctx, datumsToConstants(d))
@@ -129,6 +130,7 @@ func TestSleep(t *testing.T) {
 
 	// for error case under the strict model
 	levels[errctx.ErrGroupBadNull] = errctx.LevelError
+	levels[errctx.ErrGroupNoDefault] = errctx.LevelError
 	sessVars.StmtCtx.SetErrLevels(levels)
 	d[0].SetNull()
 	_, err = fc.getFunction(ctx, datumsToConstants(d))

pkg/lightning/backend/kv/session.go

@@ -327,6 +327,7 @@ func NewSession(options *encode.SessionOptions, logger log.Logger) *Session {
 
 	errLevels := vars.StmtCtx.ErrLevels()
 	errLevels[errctx.ErrGroupBadNull] = errctx.ResolveErrLevel(false, !sqlMode.HasStrictMode())
+	errLevels[errctx.ErrGroupNoDefault] = errctx.ResolveErrLevel(false, !sqlMode.HasStrictMode())
 	errLevels[errctx.ErrGroupDividedByZero] =
 		errctx.ResolveErrLevel(!sqlMode.HasErrorForDivisionByZeroMode(), !sqlMode.HasStrictMode())
 	vars.StmtCtx.SetErrLevels(errLevels)

pkg/lightning/errormanager/errormanager.go

@@ -150,7 +150,7 @@ const (
 	`
 
 	insertIntoConflictErrorData = `
-		INSERT INTO %s.` + ConflictErrorTableName + `
+		INSERT IGNORE INTO %s.` + ConflictErrorTableName + `
 		(task_id, table_name, index_name, key_data, row_data, raw_key, raw_value, raw_handle, raw_row, kv_type)
 		VALUES
 	`

pkg/table/column.go

@@ -506,7 +506,10 @@ func (c *Column) CheckNotNull(data *types.Datum, rowCntInLoadData uint64) error
 // error is ErrWarnNullToNotnull.
 // Otherwise, the error is ErrColumnCantNull.
 // If BadNullAsWarning is true, it will append the error as a warning, else return the error.
-func (c *Column) HandleBadNull(ec errctx.Context, d *types.Datum, rowCntInLoadData uint64) error {
+func (c *Column) HandleBadNull(
+	ec errctx.Context,
+	d *types.Datum,
+	rowCntInLoadData uint64) error {
 	if err := c.CheckNotNull(d, rowCntInLoadData); err != nil {
 		if ec.HandleError(err) == nil {
 			*d = GetZeroValue(c.ToInfo())
@@ -549,7 +552,7 @@ func GetColOriginDefaultValueWithoutStrictSQLMode(ctx expression.BuildContext, c
 // But CheckNoDefaultValueForInsert logic should only check before insert.
 func CheckNoDefaultValueForInsert(sc *stmtctx.StatementContext, col *model.ColumnInfo) error {
 	if mysql.HasNoDefaultValueFlag(col.GetFlag()) && !col.DefaultIsExpr && col.GetDefaultValue() == nil && col.GetType() != mysql.TypeEnum {
-		ignoreErr := sc.ErrGroupLevel(errctx.ErrGroupBadNull) != errctx.LevelError
+		ignoreErr := sc.ErrGroupLevel(errctx.ErrGroupNoDefault) != errctx.LevelError
 		if !ignoreErr {
 			return ErrNoDefaultValue.GenWithStackByArgs(col.Name)
 		}

pkg/table/column_test.go

@@ -484,7 +484,7 @@ func TestGetDefaultValue(t *testing.T) {
 			ctx.GetSessionVars().SQLMode = mysql.DelSQLMode(defaultMode, mysql.ModeStrictAllTables|mysql.ModeStrictTransTables)
 		}
 		levels := sc.ErrLevels()
-		levels[errctx.ErrGroupBadNull] = errctx.ResolveErrLevel(false, !tt.strict)
+		levels[errctx.ErrGroupNoDefault] = errctx.ResolveErrLevel(false, !tt.strict)
 		sc.SetErrLevels(levels)
 		val, err := GetColDefaultValue(ctx, tt.colInfo)
 		if err != nil {
@@ -506,7 +506,7 @@ func TestGetDefaultValue(t *testing.T) {
 			ctx.GetSessionVars().SQLMode = mysql.DelSQLMode(defaultMode, mysql.ModeStrictAllTables|mysql.ModeStrictTransTables)
 		}
 		levels := sc.ErrLevels()
-		levels[errctx.ErrGroupBadNull] = errctx.ResolveErrLevel(false, !tt.strict)
+		levels[errctx.ErrGroupNoDefault] = errctx.ResolveErrLevel(false, !tt.strict)
 		sc.SetErrLevels(levels)
 		val, err := GetColOriginDefaultValue(ctx, tt.colInfo)
 		if err != nil {

tests/integrationtest/r/executor/insert.result

@@ -947,7 +947,10 @@ ab
 
 ab			ab		
 ab  	ab
-ab	ab
+ab
+
+	ab
+
 select length(v), length(c) from vctt;
 length(v)	length(c)
 4	4
@@ -1713,7 +1716,7 @@ insert into t(name, b) values("chb", 3);
 Error 1062 (23000): Duplicate entry 'ch' for key 't.PRIMARY'
 insert into t(name, b) values("测试", 3);
 insert into t(name, b) values("测试", 3);
-Error 1062 (23000): Duplicate entry '�' for key 't.PRIMARY'
+Error 1062 (23000): Duplicate entry '�' for key 't.PRIMARY'
 drop table if exists t;
 create table t (i int unique key);
 insert into t values (1),(2);
@@ -1866,9 +1869,7 @@ f1	f2
 2	2
 SET sql_mode='';
 INSERT t1 VALUES (1, 1) ON DUPLICATE KEY UPDATE f2 = null;
-show warnings;
-Level	Code	Message
-Warning	1048	Column 'f2' cannot be null
+Error 1048 (23000): Column 'f2' cannot be null
 SELECT * FROM t1 order by f1;
 f1	f2
 1	0

tests/integrationtest/t/executor/insert.test

@@ -1407,8 +1407,8 @@ show warnings;
 SELECT * FROM t1 order by f1;
 
 SET sql_mode='';
+-- error 1048
 INSERT t1 VALUES (1, 1) ON DUPLICATE KEY UPDATE f2 = null;
-show warnings;
 SELECT * FROM t1 order by f1;
 set sql_mode=default;