mounter(ticdc): default value convert to the correct data type (#10804)…

… (#10829)

close #10803

cdc/entry/mounter.go

@@ -342,7 +342,7 @@ func parseJob(v []byte, startTs, CRTs uint64) (*timodel.Job, error) {
 }
 
 func datum2Column(
-	tableInfo *model.TableInfo, datums map[int64]types.Datum,
+	tableInfo *model.TableInfo, datums map[int64]types.Datum, tz *time.Location,
 ) ([]*model.Column, []types.Datum, []*timodel.ColumnInfo, []rowcodec.ColInfo, error) {
 	cols := make([]*model.Column, len(tableInfo.RowColumnsOffset))
 	rawCols := make([]types.Datum, len(tableInfo.RowColumnsOffset))
@@ -374,7 +374,7 @@ func datum2Column(
 		if exist {
 			colValue, size, warn, err = formatColVal(colDatums, colInfo)
 		} else {
-			colDatums, colValue, size, warn, err = getDefaultOrZeroValue(colInfo)
+			colDatums, colValue, size, warn, err = getDefaultOrZeroValue(colInfo, tz)
 		}
 		if err != nil {
 			return nil, nil, nil, nil, errors.Trace(err)
@@ -508,7 +508,7 @@ func (m *mounter) mountRowKVEntry(tableInfo *model.TableInfo, row *rowKVEntry, d
 	if row.PreRowExist {
 		// FIXME(leoppro): using pre table info to mounter pre column datum
 		// the pre column and current column in one event may using different table info
-		preCols, preRawCols, columnInfos, extendColumnInfos, err = datum2Column(tableInfo, row.PreRow)
+		preCols, preRawCols, columnInfos, extendColumnInfos, err = datum2Column(tableInfo, row.PreRow, m.tz)
 		if err != nil {
 			return nil, rawRow, errors.Trace(err)
 		}
@@ -537,7 +537,7 @@ func (m *mounter) mountRowKVEntry(tableInfo *model.TableInfo, row *rowKVEntry, d
 		current uint32
 	)
 	if row.RowExist {
-		cols, rawCols, columnInfos, extendColumnInfos, err = datum2Column(tableInfo, row.Row)
+		cols, rawCols, columnInfos, extendColumnInfos, err = datum2Column(tableInfo, row.Row, m.tz)
 		if err != nil {
 			return nil, rawRow, errors.Trace(err)
 		}
@@ -704,20 +704,28 @@ func formatColVal(datum types.Datum, col *timodel.ColumnInfo) (
 // https://github.com/golang/go/blob/go1.17.4/src/database/sql/driver/types.go#L236
 // Supported type is: nil, basic type(Int, Int8,..., Float32, Float64, String), Slice(uint8), other types not support
 // TODO: Check default expr support
-func getDefaultOrZeroValue(col *timodel.ColumnInfo) (types.Datum, any, int, string, error) {
-	var d types.Datum
+func getDefaultOrZeroValue(
+	col *timodel.ColumnInfo, tz *time.Location,
+) (types.Datum, any, int, string, error) {
+	var (
+		d   types.Datum
+		err error
+	)
 	// NOTICE: SHOULD use OriginDefaultValue here, more info pls ref to
 	// https://github.com/pingcap/tiflow/issues/4048
 	// FIXME: Too many corner cases may hit here, like type truncate, timezone
 	// (1) If this column is uk(no pk), will cause data inconsistency in Scenarios(2)
 	// (2) If not fix here, will cause data inconsistency in Scenarios(3) directly
 	// Ref: https://github.com/pingcap/tidb/blob/d2c352980a43bb593db81fd1db996f47af596d91/table/column.go#L489
 	if col.GetOriginDefaultValue() != nil {
-		d = types.NewDatum(col.GetOriginDefaultValue())
-		return d, d.GetValue(), sizeOfDatum(d), "", nil
-	}
-
-	if !mysql.HasNotNullFlag(col.GetFlag()) {
+		datum := types.NewDatum(col.GetOriginDefaultValue())
+		sctx := new(stmtctx.StatementContext)
+		sctx.TimeZone = tz
+		d, err = datum.ConvertTo(sctx, &col.FieldType)
+		if err != nil {
+			return d, d.GetValue(), sizeOfDatum(d), "", errors.Trace(err)
+		}
+	} else if !mysql.HasNotNullFlag(col.GetFlag()) {
 		// NOTICE: NotNullCheck need do after OriginDefaultValue check, as when TiDB meet "amend + add column default xxx",
 		// ref: https://github.com/pingcap/ticdc/issues/3929
 		// must use null if TiDB not write the column value when default value is null