GTID and other go/mysql and vstreamer optimizations

go/mysql/binlog/rbr.go

@@ -164,11 +164,9 @@ func printTimestamp(v uint32) *bytes.Buffer {
 	}
 
 	t := time.Unix(int64(v), 0).UTC()
-	year, month, day := t.Date()
-	hour, minute, second := t.Clock()
 
 	result := &bytes.Buffer{}
-	fmt.Fprintf(result, "%04d-%02d-%02d %02d:%02d:%02d", year, int(month), day, hour, minute, second)
+	result.Write(t.AppendFormat(nil, sqltypes.TimestampFormat))
 	return result
 }
 

go/mysql/binlog/rbr_test.go

@@ -23,6 +23,8 @@ import (
 
 	"vitess.io/vitess/go/sqltypes"
 	querypb "vitess.io/vitess/go/vt/proto/query"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestCellLengthAndData(t *testing.T) {
@@ -557,3 +559,10 @@ func TestCellLengthAndData(t *testing.T) {
 		}
 	}
 }
+
+func TestPrintTimestamp(t *testing.T) {
+	var timestamp uint32 = 1741794544
+
+	result := printTimestamp(timestamp).String()
+	assert.Equal(t, "2025-03-12 15:49:04", result)
+}

go/mysql/binlog_event.go

@@ -111,7 +111,7 @@ type BinlogEvent interface {
 	// GTID returns the GTID from the event, and if this event
 	// also serves as a BEGIN statement.
 	// This is only valid if IsGTID() returns true.
-	GTID(BinlogFormat) (replication.GTID, bool, error)
+	GTID(BinlogFormat) (gtid replication.GTID, hasBegin bool, lastCommitted int64, sequenceNumber int64, err error)
 	// Query returns a Query struct representing data from a QUERY_EVENT.
 	// This is only valid if IsQuery() returns true.
 	Query(BinlogFormat) (Query, error)

go/mysql/binlog_event_filepos.go

@@ -40,8 +40,8 @@ func newFilePosBinlogEvent(buf []byte) *filePosBinlogEvent {
 	return &filePosBinlogEvent{binlogEvent: binlogEvent(buf)}
 }
 
-func (*filePosBinlogEvent) GTID(BinlogFormat) (replication.GTID, bool, error) {
-	return nil, false, nil
+func (*filePosBinlogEvent) GTID(BinlogFormat) (replication.GTID, bool, int64, int64, error) {
+	return nil, false, 0, 0, nil
 }
 
 // IsSemiSyncAckRequested implements BinlogEvent.IsSemiSyncAckRequested().
@@ -224,8 +224,8 @@ func (ev filePosFakeEvent) Format() (BinlogFormat, error) {
 	return BinlogFormat{}, nil
 }
 
-func (ev filePosFakeEvent) GTID(BinlogFormat) (replication.GTID, bool, error) {
-	return nil, false, nil
+func (ev filePosFakeEvent) GTID(BinlogFormat) (replication.GTID, bool, int64, int64, error) {
+	return nil, false, 0, 0, nil
 }
 
 func (ev filePosFakeEvent) Query(BinlogFormat) (Query, error) {
@@ -304,6 +304,6 @@ func (ev filePosGTIDEvent) StripChecksum(f BinlogFormat) (BinlogEvent, []byte, e
 	return ev, nil, nil
 }
 
-func (ev filePosGTIDEvent) GTID(BinlogFormat) (replication.GTID, bool, error) {
-	return ev.gtid, false, nil
+func (ev filePosGTIDEvent) GTID(BinlogFormat) (replication.GTID, bool, int64, int64, error) {
+	return ev.gtid, false, 0, 0, nil
 }

go/mysql/binlog_event_make_test.go

@@ -159,7 +159,7 @@ func TestMariadDBGTIDEVent(t *testing.T) {
 	event, _, err := event.StripChecksum(f)
 	require.NoError(t, err, "StripChecksum failed: %v", err)
 
-	gtid, hasBegin, err := event.GTID(f)
+	gtid, hasBegin, _, _, err := event.GTID(f)
 	require.NoError(t, err, "NewMariaDBGTIDEvent().GTID() returned error: %v", err)
 	require.True(t, hasBegin, "NewMariaDBGTIDEvent() didn't store hasBegin properly.")
 
@@ -178,7 +178,7 @@ func TestMariadDBGTIDEVent(t *testing.T) {
 	event, _, err = event.StripChecksum(f)
 	require.NoError(t, err, "StripChecksum failed: %v", err)
 
-	gtid, hasBegin, err = event.GTID(f)
+	gtid, hasBegin, _, _, err = event.GTID(f)
 	require.NoError(t, err, "NewMariaDBGTIDEvent().GTID() returned error: %v", err)
 	require.False(t, hasBegin, "NewMariaDBGTIDEvent() didn't store hasBegin properly.")
 

go/mysql/binlog_event_mariadb.go

@@ -60,17 +60,18 @@ func (ev mariadbBinlogEvent) IsGTID() bool {
 //	8         sequence number
 //	4         domain ID
 //	1         flags2
-func (ev mariadbBinlogEvent) GTID(f BinlogFormat) (replication.GTID, bool, error) {
+func (ev mariadbBinlogEvent) GTID(f BinlogFormat) (replication.GTID, bool, int64, int64, error) {
 	const FLStandalone = 1
 
 	data := ev.Bytes()[f.HeaderLength:]
 	flags2 := data[8+4]
 
-	return replication.MariadbGTID{
+	gtid := replication.MariadbGTID{
 		Sequence: binary.LittleEndian.Uint64(data[:8]),
 		Domain:   binary.LittleEndian.Uint32(data[8 : 8+4]),
 		Server:   ev.ServerID(),
-	}, flags2&FLStandalone == 0, nil
+	}
+	return gtid, flags2&FLStandalone == 0, 0, 0, nil
 }
 
 // PreviousGTIDs implements BinlogEvent.PreviousGTIDs().

go/mysql/binlog_event_mariadb_test.go

@@ -60,7 +60,7 @@ func TestMariadbNotBeginGTID(t *testing.T) {
 	require.NoError(t, err)
 
 	input := mariadbBinlogEvent{binlogEvent: binlogEvent(mariadbStandaloneGTIDEvent)}
-	_, got, err := input.GTID(f)
+	_, got, _, _, err := input.GTID(f)
 	require.NoError(t, err)
 	assert.False(t, got, "%#v", input)
 }
@@ -70,7 +70,7 @@ func TestMariadbIsBeginGTID(t *testing.T) {
 	require.NoError(t, err)
 
 	input := mariadbBinlogEvent{binlogEvent: binlogEvent(mariadbBeginGTIDEvent)}
-	_, got, err := input.GTID(f)
+	_, got, _, _, err := input.GTID(f)
 	require.NoError(t, err)
 	assert.True(t, got, "%#v", input)
 }
@@ -81,7 +81,7 @@ func TestMariadbStandaloneBinlogEventGTID(t *testing.T) {
 
 	input := mariadbBinlogEvent{binlogEvent: binlogEvent(mariadbStandaloneGTIDEvent)}
 	want := replication.MariadbGTID{Domain: 0, Server: 62344, Sequence: 9}
-	got, hasBegin, err := input.GTID(f)
+	got, hasBegin, _, _, err := input.GTID(f)
 	assert.NoError(t, err)
 	assert.False(t, hasBegin)
 	assert.Equal(t, want, got)
@@ -93,7 +93,7 @@ func TestMariadbBinlogEventGTID(t *testing.T) {
 
 	input := mariadbBinlogEvent{binlogEvent: binlogEvent(mariadbBeginGTIDEvent)}
 	want := replication.MariadbGTID{Domain: 0, Server: 62344, Sequence: 10}
-	got, hasBegin, err := input.GTID(f)
+	got, hasBegin, _, _, err := input.GTID(f)
 	assert.NoError(t, err)
 	assert.True(t, hasBegin)
 	assert.Equal(t, want, got)

go/mysql/binlog_event_mysql56.go

@@ -60,12 +60,27 @@ func (ev mysql56BinlogEvent) IsGTID() bool {
 //	1         flags
 //	16        SID (server UUID)
 //	8         GNO (sequence number, signed int)
-func (ev mysql56BinlogEvent) GTID(f BinlogFormat) (replication.GTID, bool, error) {
+//	1         lt_type
+//	8         last_committed
+//	8         sequence_number
+func (ev mysql56BinlogEvent) GTID(f BinlogFormat) (gtid replication.GTID, hasBegin bool, lastCommitted int64, sequenceNumber int64, err error) {
 	data := ev.Bytes()[f.HeaderLength:]
 	var sid replication.SID
-	copy(sid[:], data[1:1+16])
-	gno := int64(binary.LittleEndian.Uint64(data[1+16 : 1+16+8]))
-	return replication.Mysql56GTID{Server: sid, Sequence: gno}, false /* hasBegin */, nil
+	pos := 1
+	copy(sid[:], data[pos:pos+16])
+	pos += 16 // end of SID
+	gno := int64(binary.LittleEndian.Uint64(data[pos : pos+8]))
+	pos += 8 // end of GNO
+	pos += 1 // end of lt_type
+	if len(data) >= pos+8 {
+		lastCommitted = int64(binary.LittleEndian.Uint64(data[pos : pos+8]))
+	}
+	pos += 8 // end of last_committed
+	if len(data) >= pos+8 {
+		sequenceNumber = int64(binary.LittleEndian.Uint64(data[pos : pos+8]))
+	}
+	// pos += 8 // end of sequence_number
+	return replication.Mysql56GTID{Server: sid, Sequence: gno}, false /* hasBegin */, lastCommitted, sequenceNumber, nil
 }
 
 // PreviousGTIDs implements BinlogEvent.PreviousGTIDs().

go/mysql/binlog_event_mysql56_test.go

@@ -34,7 +34,7 @@ import (
 // Sample event data for MySQL 5.6.
 var (
 	mysql56FormatEvent             = NewMysql56BinlogEvent([]byte{0x78, 0x4e, 0x49, 0x55, 0xf, 0x64, 0x0, 0x0, 0x0, 0x74, 0x0, 0x0, 0x0, 0x78, 0x0, 0x0, 0x0, 0x1, 0x0, 0x4, 0x0, 0x35, 0x2e, 0x36, 0x2e, 0x32, 0x34, 0x2d, 0x6c, 0x6f, 0x67, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x78, 0x4e, 0x49, 0x55, 0x13, 0x38, 0xd, 0x0, 0x8, 0x0, 0x12, 0x0, 0x4, 0x4, 0x4, 0x4, 0x12, 0x0, 0x0, 0x5c, 0x0, 0x4, 0x1a, 0x8, 0x0, 0x0, 0x0, 0x8, 0x8, 0x8, 0x2, 0x0, 0x0, 0x0, 0xa, 0xa, 0xa, 0x19, 0x19, 0x0, 0x1, 0x18, 0x4a, 0xf, 0xca})
-	mysql56GTIDEvent               = NewMysql56BinlogEvent([]byte{0xff, 0x4e, 0x49, 0x55, 0x21, 0x64, 0x0, 0x0, 0x0, 0x30, 0x0, 0x0, 0x0, 0xf5, 0x2, 0x0, 0x0, 0x0, 0x0, 0x1, 0x43, 0x91, 0x92, 0xbd, 0xf3, 0x7c, 0x11, 0xe4, 0xbb, 0xeb, 0x2, 0x42, 0xac, 0x11, 0x3, 0x5a, 0x4, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x48, 0x45, 0x82, 0x27})
+	mysql56GTIDEvent               = NewMysql56BinlogEvent([]byte{0xff, 0x4e, 0x49, 0x55, 0x21, 0x64, 0x0, 0x0, 0x0, 0x30, 0x0, 0x0, 0x0, 0xf5, 0x2, 0x0, 0x0, 0x0, 0x0, 0x1, 0x43, 0x91, 0x92, 0xbd, 0xf3, 0x7c, 0x11, 0xe4, 0xbb, 0xeb, 0x2, 0x42, 0xac, 0x11, 0x3, 0x5a, 0x4, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 /* lt_type: */, 0x0 /* last_committed: */, 0x7, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 /* sequence_number: */, 0x9, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x48, 0x45, 0x82, 0x27})
 	mysql56QueryEvent              = NewMysql56BinlogEvent([]byte{0xff, 0x4e, 0x49, 0x55, 0x2, 0x64, 0x0, 0x0, 0x0, 0x77, 0x0, 0x0, 0x0, 0xdb, 0x3, 0x0, 0x0, 0x0, 0x0, 0x3d, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x4, 0x0, 0x0, 0x21, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0, 0x20, 0x0, 0x0, 0x0, 0x0, 0x0, 0x6, 0x3, 0x73, 0x74, 0x64, 0x4, 0x8, 0x0, 0x8, 0x0, 0x21, 0x0, 0xc, 0x1, 0x74, 0x65, 0x73, 0x74, 0x0, 0x74, 0x65, 0x73, 0x74, 0x0, 0x69, 0x6e, 0x73, 0x65, 0x72, 0x74, 0x20, 0x69, 0x6e, 0x74, 0x6f, 0x20, 0x74, 0x65, 0x73, 0x74, 0x5f, 0x74, 0x61, 0x62, 0x6c, 0x65, 0x20, 0x28, 0x6d, 0x73, 0x67, 0x29, 0x20, 0x76, 0x61, 0x6c, 0x75, 0x65, 0x73, 0x20, 0x28, 0x27, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x27, 0x29, 0x92, 0x12, 0x79, 0xc3})
 	mysql56SemiSyncNoAckQueryEvent = NewMysql56BinlogEvent([]byte{0xef, 0x00, 0xff, 0x4e, 0x49, 0x55, 0x2, 0x64, 0x0, 0x0, 0x0, 0x77, 0x0, 0x0, 0x0, 0xdb, 0x3, 0x0, 0x0, 0x0, 0x0, 0x3d, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x4, 0x0, 0x0, 0x21, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0, 0x20, 0x0, 0x0, 0x0, 0x0, 0x0, 0x6, 0x3, 0x73, 0x74, 0x64, 0x4, 0x8, 0x0, 0x8, 0x0, 0x21, 0x0, 0xc, 0x1, 0x74, 0x65, 0x73, 0x74, 0x0, 0x74, 0x65, 0x73, 0x74, 0x0, 0x69, 0x6e, 0x73, 0x65, 0x72, 0x74, 0x20, 0x69, 0x6e, 0x74, 0x6f, 0x20, 0x74, 0x65, 0x73, 0x74, 0x5f, 0x74, 0x61, 0x62, 0x6c, 0x65, 0x20, 0x28, 0x6d, 0x73, 0x67, 0x29, 0x20, 0x76, 0x61, 0x6c, 0x75, 0x65, 0x73, 0x20, 0x28, 0x27, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x27, 0x29, 0x92, 0x12, 0x79, 0xc3})
 	mysql56SemiSyncAckQueryEvent   = NewMysql56BinlogEvent([]byte{0xef, 0x01, 0xff, 0x4e, 0x49, 0x55, 0x2, 0x64, 0x0, 0x0, 0x0, 0x77, 0x0, 0x0, 0x0, 0xdb, 0x3, 0x0, 0x0, 0x0, 0x0, 0x3d, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x4, 0x0, 0x0, 0x21, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0, 0x20, 0x0, 0x0, 0x0, 0x0, 0x0, 0x6, 0x3, 0x73, 0x74, 0x64, 0x4, 0x8, 0x0, 0x8, 0x0, 0x21, 0x0, 0xc, 0x1, 0x74, 0x65, 0x73, 0x74, 0x0, 0x74, 0x65, 0x73, 0x74, 0x0, 0x69, 0x6e, 0x73, 0x65, 0x72, 0x74, 0x20, 0x69, 0x6e, 0x74, 0x6f, 0x20, 0x74, 0x65, 0x73, 0x74, 0x5f, 0x74, 0x61, 0x62, 0x6c, 0x65, 0x20, 0x28, 0x6d, 0x73, 0x67, 0x29, 0x20, 0x76, 0x61, 0x6c, 0x75, 0x65, 0x73, 0x20, 0x28, 0x27, 0x68, 0x65, 0x6c, 0x6c, 0x6f, 0x27, 0x29, 0x92, 0x12, 0x79, 0xc3})
@@ -90,10 +90,12 @@ func TestMysql56GTID(t *testing.T) {
 		Server:   replication.SID{0x43, 0x91, 0x92, 0xbd, 0xf3, 0x7c, 0x11, 0xe4, 0xbb, 0xeb, 0x2, 0x42, 0xac, 0x11, 0x3, 0x5a},
 		Sequence: 4,
 	}
-	got, hasBegin, err := input.GTID(format)
+	got, hasBegin, lastCommitted, sequenceNumber, err := input.GTID(format)
 	require.NoError(t, err, "GTID() error: %v", err)
 	assert.False(t, hasBegin, "GTID() returned hasBegin")
 	assert.Equal(t, want, got, "GTID() = %#v, want %#v", got, want)
+	assert.Equal(t, int64(7), lastCommitted)
+	assert.Equal(t, int64(9), sequenceNumber)
 }
 
 func TestMysql56DecodeTransactionPayload(t *testing.T) {

go/mysql/endtoend/replication_test.go

@@ -230,7 +230,7 @@ func TestRowReplicationWithRealDatabase(t *testing.T) {
 		switch {
 		case be.IsGTID():
 			// We expect one of these at least.
-			gtid, hasBegin, err := be.GTID(f)
+			gtid, hasBegin, _, _, err := be.GTID(f)
 			if err != nil {
 				t.Fatalf("GTID event is broken: %v", err)
 			}

go/mysql/replication/filepos_gtid.go

@@ -69,6 +69,10 @@ func (gtid FilePosGTID) Flavor() string {
 	return FilePosFlavorID
 }
 
+func (gtid FilePosGTID) Empty() bool {
+	return gtid.File == ""
+}
+
 // SequenceDomain implements GTID.SequenceDomain().
 func (gtid FilePosGTID) SequenceDomain() any {
 	return nil
@@ -137,6 +141,11 @@ func (gtid FilePosGTID) AddGTID(other GTID) GTIDSet {
 	return filePosOther
 }
 
+// AddGTIDInPlace implements GTIDSet.AddGTIDInPlace().
+func (gtid FilePosGTID) AddGTIDInPlace(other GTID) GTIDSet {
+	return gtid.AddGTID(other)
+}
+
 // Union implements GTIDSet.Union().
 func (gtid FilePosGTID) Union(other GTIDSet) GTIDSet {
 	filePosOther, ok := other.(FilePosGTID)
@@ -147,6 +156,13 @@ func (gtid FilePosGTID) Union(other GTIDSet) GTIDSet {
 	return filePosOther
 }
 
+// Union implements GTIDSet.Union().
+func (gtid FilePosGTID) UnionInPlace(other GTIDSet) GTIDSet {
+	gtid = gtid.Union(other).(FilePosGTID)
+
+	return gtid
+}
+
 // Last returns last filePosition
 // For filePos based GTID we have only one position
 // here we will just return the current filePos

go/mysql/replication/gtid_set.go

@@ -34,6 +34,9 @@ type GTIDSet interface {
 	// registered in the transactionSetParsers map.
 	Flavor() string
 
+	// Empty returns true when the GTID has no entries
+	Empty() bool
+
 	// ContainsGTID returns true if the set contains the specified transaction.
 	ContainsGTID(GTID) bool
 
@@ -47,9 +50,15 @@ type GTIDSet interface {
 	// AddGTID returns a new GTIDSet that is expanded to contain the given GTID.
 	AddGTID(GTID) GTIDSet
 
+	// AddGTID returns a new GTIDSet that is expanded to contain the given GTID, modifying the receiver GTID set
+	AddGTIDInPlace(GTID) GTIDSet
+
 	// Union returns a union of the receiver GTIDSet and the supplied GTIDSet.
 	Union(GTIDSet) GTIDSet
 
+	// UnionInPlace returns a union of the receiver GTIDSet and the supplied GTIDSet, modifying the receiver GTID set
+	UnionInPlace(GTIDSet) GTIDSet
+
 	// Union returns a union of the receiver GTIDSet and the supplied GTIDSet.
 	Last() string
 }

go/mysql/replication/gtid_test.go

@@ -177,19 +177,22 @@ type fakeGTID struct {
 func (f fakeGTID) String() string    { return f.value }
 func (f fakeGTID) Last() string      { panic("not implemented") }
 func (f fakeGTID) Flavor() string    { return f.flavor }
+func (f fakeGTID) Empty() bool       { return false }
 func (fakeGTID) SourceServer() any   { return int(1) }
 func (fakeGTID) SequenceNumber() any { return int(1) }
 func (fakeGTID) SequenceDomain() any { return int(1) }
 func (f fakeGTID) GTIDSet() GTIDSet  { return nil }
 
-func (fakeGTID) ContainsGTID(GTID) bool  { return false }
-func (fakeGTID) Contains(GTIDSet) bool   { return false }
-func (f fakeGTID) Union(GTIDSet) GTIDSet { return f }
+func (fakeGTID) ContainsGTID(GTID) bool         { return false }
+func (fakeGTID) Contains(GTIDSet) bool          { return false }
+func (f fakeGTID) Union(GTIDSet) GTIDSet        { return f }
+func (f fakeGTID) UnionInPlace(GTIDSet) GTIDSet { return f }
 func (f fakeGTID) Equal(other GTIDSet) bool {
 	otherFake, ok := other.(fakeGTID)
 	if !ok {
 		return false
 	}
 	return f == otherFake
 }
-func (fakeGTID) AddGTID(GTID) GTIDSet { return nil }
+func (fakeGTID) AddGTID(GTID) GTIDSet        { return nil }
+func (fakeGTID) AddGTIDInPlace(GTID) GTIDSet { return nil }

go/mysql/replication/mariadb_gtid.go

@@ -148,6 +148,10 @@ func (gtidSet MariadbGTIDSet) Flavor() string {
 	return MariadbFlavorID
 }
 
+func (gtidSet MariadbGTIDSet) Empty() bool {
+	return len(gtidSet) == 0
+}
+
 // ContainsGTID implements GTIDSet.ContainsGTID().
 func (gtidSet MariadbGTIDSet) ContainsGTID(other GTID) bool {
 	if other == nil {
@@ -216,6 +220,19 @@ func (gtidSet MariadbGTIDSet) AddGTID(other GTID) GTIDSet {
 	return newSet
 }
 
+// AddGTID implements GTIDSet.AddGTID().
+func (gtidSet MariadbGTIDSet) AddGTIDInPlace(other GTID) GTIDSet {
+	if other == nil {
+		return gtidSet
+	}
+	mdbOther, ok := other.(MariadbGTID)
+	if !ok {
+		return gtidSet
+	}
+	gtidSet.addGTID(mdbOther)
+	return gtidSet
+}
+
 // Union implements GTIDSet.Union(). This is a pure method, and does not mutate the receiver.
 func (gtidSet MariadbGTIDSet) Union(other GTIDSet) GTIDSet {
 	if gtidSet == nil && other != nil {
@@ -237,6 +254,13 @@ func (gtidSet MariadbGTIDSet) Union(other GTIDSet) GTIDSet {
 	return newSet
 }
 
+// Union implements GTIDSet.Union().
+func (gtid MariadbGTIDSet) UnionInPlace(other GTIDSet) GTIDSet {
+	gtid = gtid.Union(other).(MariadbGTIDSet)
+
+	return gtid
+}
+
 // Last returns the last gtid
 func (gtidSet MariadbGTIDSet) Last() string {
 	// Sort domains so the string format is deterministic.

go/mysql/replication/mysql56_gtid.go

@@ -33,6 +33,10 @@ var (
 	ErrExpectMysql56Flavor = vterrors.Errorf(vtrpc.Code_INVALID_ARGUMENT, "expected MySQL GTID position but found a different or invalid format.")
 )
 
+func ParseMysql56GTID(s string) (GTID, error) {
+	return parseMysql56GTID(s)
+}
+
 // parseMysql56GTID is registered as a GTID parser.
 func parseMysql56GTID(s string) (GTID, error) {
 	// Split into parts.
@@ -94,8 +98,7 @@ func ParseSID(s string) (sid SID, err error) {
 type Mysql56GTID struct {
 	// Server is the SID of the server that originally committed the transaction.
 	Server SID
-	// Sequence is the sequence number of the transaction within a given Server's
-	// scope.
+	// Sequence is the sequence number of the transaction within a given Server's scope.
 	Sequence int64
 }
 
@@ -126,7 +129,9 @@ func (gtid Mysql56GTID) SequenceNumber() any {
 
 // GTIDSet implements GTID.GTIDSet().
 func (gtid Mysql56GTID) GTIDSet() GTIDSet {
-	return Mysql56GTIDSet{}.AddGTID(gtid)
+	return Mysql56GTIDSet{
+		gtid.Server: []interval{{start: gtid.Sequence, end: gtid.Sequence}},
+	}
 }
 
 func init() {