executor: fix a bug that can not insert null into a not null column in the empty SQL mode (#21237)

executor/executor.go

@@ -1686,9 +1686,9 @@ func ResetContextOfStmt(ctx sessionctx.Context, s ast.StmtNode) (err error) {
 		sc.InInsertStmt = true
 		// For insert statement (not for update statement), disabling the StrictSQLMode
 		// should make TruncateAsWarning and DividedByZeroAsWarning,
-		// but should not make DupKeyAsWarning or BadNullAsWarning,
+		// but should not make DupKeyAsWarning.
 		sc.DupKeyAsWarning = stmt.IgnoreErr
-		sc.BadNullAsWarning = stmt.IgnoreErr
+		sc.BadNullAsWarning = !vars.StrictSQLMode || stmt.IgnoreErr
 		sc.IgnoreNoPartition = stmt.IgnoreErr
 		sc.TruncateAsWarning = !vars.StrictSQLMode || stmt.IgnoreErr
 		sc.DividedByZeroAsWarning = !vars.StrictSQLMode || stmt.IgnoreErr

executor/executor_test.go

@@ -2120,14 +2120,14 @@ func (s *testSuiteP2) TestSQLMode(c *C) {
 	tk.MustExec("set sql_mode = ''")
 	tk.MustExec("insert t values ()")
 	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1364 Field 'a' doesn't have a default value"))
-	_, err = tk.Exec("insert t values (null)")
-	c.Check(err, NotNil)
+	tk.MustExec("insert t values (null)")
+	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1048 Column 'a' cannot be null"))
 	tk.MustExec("insert ignore t values (null)")
 	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1048 Column 'a' cannot be null"))
 	tk.MustExec("insert t select null")
 	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1048 Column 'a' cannot be null"))
 	tk.MustExec("insert t values (1000)")
-	tk.MustQuery("select * from t order by a").Check(testkit.Rows("0", "0", "0", "127"))
+	tk.MustQuery("select * from t order by a").Check(testkit.Rows("0", "0", "0", "0", "127"))
 
 	tk.MustExec("insert tdouble values (10.23)")
 	tk.MustQuery("select * from tdouble").Check(testkit.Rows("9.99"))

executor/insert_common.go

@@ -417,10 +417,6 @@ func insertRowsFromSelect(ctx context.Context, base insertCommon) error {
 	rows := make([][]types.Datum, 0, chk.Capacity())
 
 	sessVars := e.ctx.GetSessionVars()
-	if !sessVars.StrictSQLMode {
-		// If StrictSQLMode is disabled and it is a insert-select statement, it also handle BadNullAsWarning.
-		sessVars.StmtCtx.BadNullAsWarning = true
-	}
 	batchInsert := sessVars.BatchInsert && !sessVars.InTxn() && config.GetGlobalConfig().EnableBatchDML
 	batchSize := sessVars.DMLBatchSize
 	memUsageOfRows := int64(0)

executor/write_test.go

@@ -735,8 +735,8 @@ commit;`
 	tk.MustQuery(`SELECT * FROM t1 order by f1;`).Check(testkit.Rows("1 0", "2 2"))
 
 	tk.MustExec(`SET sql_mode='';`)
-	_, err = tk.Exec(`INSERT t1 VALUES (1, 1) ON DUPLICATE KEY UPDATE f2 = null;`)
-	c.Assert(err, NotNil)
+	tk.MustExec(`INSERT t1 VALUES (1, 1) ON DUPLICATE KEY UPDATE f2 = null;`)
+	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1048 Column 'f2' cannot be null"))
 	tk.MustQuery(`SELECT * FROM t1 order by f1;`).Check(testkit.Rows("1 0", "2 2"))
 }
 

expression/integration_test.go

@@ -3106,6 +3106,17 @@ func (s *testIntegrationSuite2) TestBuiltin(c *C) {
 	result.Check(testkit.Rows("0"))
 }
 
+func (s *testIntegrationSuite2) TestIssue11648(c *C) {
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists t")
+	tk.MustExec("create table t (id int NOT NULL DEFAULT 8);")
+	tk.MustExec("SET sql_mode = '';")
+	tk.MustExec("insert into t values (1), (NULL), (2);")
+	tk.MustQuery("show warnings").Check(testkit.Rows("Warning 1048 Column 'id' cannot be null"))
+	tk.MustQuery("select * from t").Check(testkit.Rows("1", "0", "2"))
+}
+
 func (s *testIntegrationSuite) TestInfoBuiltin(c *C) {
 	defer s.cleanEnv(c)
 	tk := testkit.NewTestKit(c, s.store)

table/column.go

@@ -567,14 +567,14 @@ func getColDefaultValueFromNil(ctx sessionctx.Context, col *model.ColumnInfo) (t
 	}
 	vars := ctx.GetSessionVars()
 	sc := vars.StmtCtx
-	if sc.BadNullAsWarning {
-		sc.AppendWarning(ErrColumnCantNull.FastGenByArgs(col.Name))
-		return GetZeroValue(col), nil
-	}
 	if !vars.StrictSQLMode {
 		sc.AppendWarning(ErrNoDefaultValue.FastGenByArgs(col.Name))
 		return GetZeroValue(col), nil
 	}
+	if sc.BadNullAsWarning {
+		sc.AppendWarning(ErrColumnCantNull.FastGenByArgs(col.Name))
+		return GetZeroValue(col), nil
+	}
 	return types.Datum{}, ErrNoDefaultValue.FastGenByArgs(col.Name)
 }