table: Revert "table: fix the issue that the default value for BIT column is wrong (#57303)"

pkg/ddl/ddl_api.go

@@ -64,7 +64,6 @@ import (
 	"github.com/pingcap/tidb/pkg/util/dbterror"
 	"github.com/pingcap/tidb/pkg/util/domainutil"
 	"github.com/pingcap/tidb/pkg/util/hack"
-	"github.com/pingcap/tidb/pkg/util/intest"
 	"github.com/pingcap/tidb/pkg/util/logutil"
 	"github.com/pingcap/tidb/pkg/util/mathutil"
 	"github.com/pingcap/tidb/pkg/util/memory"
@@ -1032,21 +1031,6 @@ func checkColumnDefaultValue(ctx sessionctx.Context, col *table.Column, value in
 			}
 		}
 	}
-	if value != nil && col.GetType() == mysql.TypeBit {
-		v, ok := value.(string)
-		if !ok {
-			return hasDefaultValue, value, types.ErrInvalidDefault.GenWithStackByArgs(col.Name.O)
-		}
-
-		uintVal, err := types.BinaryLiteral(v).ToInt(ctx.GetSessionVars().StmtCtx)
-		if err != nil {
-			return hasDefaultValue, value, types.ErrInvalidDefault.GenWithStackByArgs(col.Name.O)
-		}
-		intest.Assert(col.GetFlen() > 0 && col.GetFlen() <= 64)
-		if col.GetFlen() < 64 && uintVal >= 1<<(uint64(col.GetFlen())) {
-			return hasDefaultValue, value, types.ErrInvalidDefault.GenWithStackByArgs(col.Name.O)
-		}
-	}
 	return hasDefaultValue, value, nil
 }
 
@@ -5299,14 +5283,13 @@ func SetDefaultValue(ctx sessionctx.Context, col *table.Column, option *ast.Colu
 		}
 		col.DefaultIsExpr = isSeqExpr
 	}
-	if !col.DefaultIsExpr {
-		if hasDefaultValue, value, err = checkColumnDefaultValue(ctx, col, value); err != nil {
-			return hasDefaultValue, errors.Trace(err)
-		}
-		value, err = convertTimestampDefaultValToUTC(ctx, value, col)
-		if err != nil {
-			return hasDefaultValue, errors.Trace(err)
-		}
+
+	if hasDefaultValue, value, err = checkColumnDefaultValue(ctx, col, value); err != nil {
+		return hasDefaultValue, errors.Trace(err)
+	}
+	value, err = convertTimestampDefaultValToUTC(ctx, value, col)
+	if err != nil {
+		return hasDefaultValue, errors.Trace(err)
 	}
 	err = setDefaultValueWithBinaryPadding(col, value)
 	if err != nil {

pkg/executor/test/writetest/write_test.go

@@ -1300,7 +1300,7 @@ func TestIssue18681(t *testing.T) {
 	tk := testkit.NewTestKit(t, store)
 	tk.MustExec("use test")
 	createSQL := `drop table if exists load_data_test;
-		create table load_data_test (a bit(1),b bit(1),c bit(1),d bit(1),e bit(32),f bit(1));`
+		create table load_data_test (a bit(1),b bit(1),c bit(1),d bit(1));`
 	tk.MustExec(createSQL)
 	tk.MustExec("load data local infile '/tmp/nonexistence.csv' ignore into table load_data_test")
 	ctx := tk.Session().(sessionctx.Context)
@@ -1310,7 +1310,7 @@ func TestIssue18681(t *testing.T) {
 	require.NotNil(t, ld)
 
 	deleteSQL := "delete from load_data_test"
-	selectSQL := "select bin(a), bin(b), bin(c), bin(d), bin(e), bin(f) from load_data_test;"
+	selectSQL := "select bin(a), bin(b), bin(c), bin(d) from load_data_test;"
 	ctx.GetSessionVars().StmtCtx.DupKeyAsWarning = true
 	ctx.GetSessionVars().StmtCtx.BadNullAsWarning = true
 	ctx.GetSessionVars().StmtCtx.NoDefaultAsWarning = true
@@ -1322,7 +1322,7 @@ func TestIssue18681(t *testing.T) {
 	}()
 	sc.IgnoreTruncate.Store(false)
 	tests := []testCase{
-		{[]byte("true\tfalse\t0\t1\tb'1'\tb'1'\n"), []string{"1|1|1|1|1100010001001110011000100100111|1"}, "Records: 1  Deleted: 0  Skipped: 0  Warnings: 5"},
+		{[]byte("true\tfalse\t0\t1\n"), []string{"1|0|0|1"}, "Records: 1  Deleted: 0  Skipped: 0  Warnings: 0"},
 	}
 	checkCases(tests, ld, t, tk, ctx, selectSQL, deleteSQL)
 	require.Equal(t, uint16(0), sc.WarningCount())

pkg/types/datum.go

@@ -1576,13 +1576,38 @@ func (d *Datum) ConvertToMysqlYear(sc *stmtctx.StatementContext, target *FieldTy
 	return ret, errors.Trace(err)
 }
 
+func (d *Datum) convertStringToMysqlBit(sc *stmtctx.StatementContext) (uint64, error) {
+	bitStr, err := ParseBitStr(BinaryLiteral(d.b).ToString())
+	if err != nil {
+		// It cannot be converted to bit type, so we need to convert it to int type.
+		return BinaryLiteral(d.b).ToInt(sc)
+	}
+	return bitStr.ToInt(sc)
+}
+
 func (d *Datum) convertToMysqlBit(sc *stmtctx.StatementContext, target *FieldType) (Datum, error) {
 	var ret Datum
 	var uintValue uint64
 	var err error
 	switch d.k {
-	case KindString, KindBytes:
+	case KindBytes:
 		uintValue, err = BinaryLiteral(d.b).ToInt(sc)
+	case KindString:
+		// For single bit value, we take string like "true", "1" as 1, and "false", "0" as 0,
+		// this behavior is not documented in MySQL, but it behaves so, for more information, see issue #18681
+		s := BinaryLiteral(d.b).ToString()
+		if target.GetFlen() == 1 {
+			switch strings.ToLower(s) {
+			case "true", "1":
+				uintValue = 1
+			case "false", "0":
+				uintValue = 0
+			default:
+				uintValue, err = d.convertStringToMysqlBit(sc)
+			}
+		} else {
+			uintValue, err = d.convertStringToMysqlBit(sc)
+		}
 	case KindInt64:
 		// if input kind is int64 (signed), when trans to bit, we need to treat it as unsigned
 		d.k = KindUint64

pkg/types/datum_test.go

@@ -527,37 +527,24 @@ func prepareCompareDatums() ([]Datum, []Datum) {
 
 func TestStringToMysqlBit(t *testing.T) {
 	tests := []struct {
-		a         Datum
-		out       []byte
-		flen      int
-		truncated bool
+		a   Datum
+		out []byte
 	}{
-		{NewStringDatum("true"), []byte{1}, 1, true},
-		{NewStringDatum("true"), []byte{0x74, 0x72, 0x75, 0x65}, 32, false},
-		{NewStringDatum("false"), []byte{0x1}, 1, true},
-		{NewStringDatum("false"), []byte{0x66, 0x61, 0x6c, 0x73, 0x65}, 40, false},
-		{NewStringDatum("1"), []byte{1}, 1, true},
-		{NewStringDatum("1"), []byte{0x31}, 8, false},
-		{NewStringDatum("0"), []byte{1}, 1, true},
-		{NewStringDatum("0"), []byte{0x30}, 8, false},
-		{NewStringDatum("b'1'"), []byte{0x62, 0x27, 0x31, 0x27}, 32, false},
-		{NewStringDatum("b'0'"), []byte{0x62, 0x27, 0x30, 0x27}, 32, false},
+		{NewStringDatum("true"), []byte{1}},
+		{NewStringDatum("false"), []byte{0}},
+		{NewStringDatum("1"), []byte{1}},
+		{NewStringDatum("0"), []byte{0}},
+		{NewStringDatum("b'1'"), []byte{1}},
+		{NewStringDatum("b'0'"), []byte{0}},
 	}
 	sc := stmtctx.NewStmtCtx()
 	sc.IgnoreTruncate.Store(true)
+	tp := NewFieldType(mysql.TypeBit)
+	tp.SetFlen(1)
 	for _, tt := range tests {
-		t.Run(fmt.Sprintf("%s %d %t", tt.a.GetString(), tt.flen, tt.truncated), func(t *testing.T) {
-			tp := NewFieldType(mysql.TypeBit)
-			tp.SetFlen(tt.flen)
-
-			bin, err := tt.a.convertToMysqlBit(sc, tp)
-			if tt.truncated {
-				require.Contains(t, err.Error(), "Data Too Long")
-			} else {
-				require.NoError(t, err)
-			}
-			require.Equal(t, tt.out, bin.b)
-		})
+		bin, err := tt.a.convertToMysqlBit(nil, tp)
+		require.NoError(t, err)
+		require.Equal(t, tt.out, bin.b)
 	}
 }
 

tests/integrationtest/r/ddl/column.result

@@ -65,15 +65,3 @@ t	CREATE TABLE `t` (
   `a` decimal(10,0) DEFAULT NULL,
   `b` decimal(10,0) DEFAULT NULL
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin
-drop table if exists t;
-create table t(a bit(2) default b'111');
-Error 1067 (42000): Invalid default value for 'a'
-create table t(a bit(65) default b'111');
-Error 1439 (42000): Display width out of range for column 'a' (max = 64)
-create table t(a bit(64) default b'1111111111111111111111111111111111111111111111111111111111111111');
-drop table t;
-create table t(a bit(3) default b'111');
-drop table t;
-create table t(a bit(3) default b'000111');
-drop table t;
-create table t(a bit(32) default b'1111111111111111111111111111111');

tests/integrationtest/r/table/tables.result

@@ -6,9 +6,3 @@ select count(distinct(_tidb_rowid>>48)) from shard_t;
 count(distinct(_tidb_rowid>>48))
 4
 set @@tidb_shard_allocate_step=default;
-drop table if exists t;
-create table t(a bit(32) default b'1100010001001110011000100100111');
-insert into t values ();
-select hex(a) from t;
-hex(a)
-62273127

tests/integrationtest/t/ddl/column.test

@@ -22,17 +22,3 @@ show create table t2;
 drop table if exists t;
 create table t(a decimal(0,0), b decimal(0));
 show create table t;
-
-# TestTooLongDefaultValueForBit
-drop table if exists t;
--- error 1067
-create table t(a bit(2) default b'111');
--- error 1439
-create table t(a bit(65) default b'111');
-create table t(a bit(64) default b'1111111111111111111111111111111111111111111111111111111111111111');
-drop table t;
-create table t(a bit(3) default b'111');
-drop table t;
-create table t(a bit(3) default b'000111');
-drop table t;
-create table t(a bit(32) default b'1111111111111111111111111111111');

tests/integrationtest/t/table/tables.test

@@ -5,9 +5,3 @@ set @@tidb_shard_allocate_step=3;
 insert into shard_t values (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (11);
 select count(distinct(_tidb_rowid>>48)) from shard_t;
 set @@tidb_shard_allocate_step=default;
-
-# TestInsertBitDefaultValue
-drop table if exists t;
-create table t(a bit(32) default b'1100010001001110011000100100111');
-insert into t values ();
-select hex(a) from t;