- row copy and row events are now handled by a single routine which prioritizes events over rowcopy

- Supporting `--throttle-file-flag`
- Printing status
- Supporting transactional table syntax
- code cleanup; refactoring
- proper use of atomic where required
- iterations are in changelog (erm... maybe too much)
- `LOCK TABLES`, `UNLOCK TABLES` working

go/base/context.go

@@ -7,6 +7,8 @@ package base
 
 import (
 	"fmt"
+	"strings"
+	"sync/atomic"
 	"time"
 
 	"github.com/github/gh-osc/go/mysql"
@@ -36,7 +38,7 @@ type MigrationContext struct {
 	CountTableRows                      bool
 	RowsEstimate                        int64
 	UsedRowsEstimateMethod              RowsEstimateMethod
-	ChunkSize                           int
+	ChunkSize                           int64
 	OriginalBinlogFormat                string
 	OriginalBinlogRowImage              string
 	AllowedRunningOnMaster              bool
@@ -52,6 +54,8 @@ type MigrationContext struct {
 	RowCopyStartTime                    time.Time
 	CurrentLag                          int64
 	MaxLagMillisecondsThrottleThreshold int64
+	ThrottleFlagFile                    string
+	TotalRowsCopied                     int64
 
 	IsThrottled      func() bool
 	CanStopStreaming func() bool
@@ -107,3 +111,33 @@ func (this *MigrationContext) HasMigrationRange() bool {
 func (this *MigrationContext) MaxRetries() int {
 	return maxRetries
 }
+
+func (this *MigrationContext) IsTransactionalTable() bool {
+	switch strings.ToLower(this.TableEngine) {
+	case "innodb":
+		{
+			return true
+		}
+	case "tokudb":
+		{
+			return true
+		}
+	}
+	return false
+}
+
+// ElapsedTime returns time since very beginning of the process
+func (this *MigrationContext) ElapsedTime() time.Duration {
+	return time.Now().Sub(this.StartTime)
+}
+
+// ElapsedRowCopyTime returns time since starting to copy chunks of rows
+func (this *MigrationContext) ElapsedRowCopyTime() time.Duration {
+	return time.Now().Sub(this.RowCopyStartTime)
+}
+
+// GetTotalRowsCopied returns the accurate number of rows being copied (affected)
+// This is not exactly the same as the rows being iterated via chunks, but potentially close enough
+func (this *MigrationContext) GetTotalRowsCopied() int64 {
+	return atomic.LoadInt64(&this.TotalRowsCopied)
+}

go/binlog/gomysql_reader.go

@@ -120,65 +120,3 @@ func (this *GoMySQLReader) StreamEvents(canStopStreaming func() bool, entriesCha
 
 	return nil
 }
-
-// ReadEntries will read binlog entries from parsed text output of `mysqlbinlog` utility
-func (this *GoMySQLReader) ReadEntries(logFile string, startPos uint64, stopPos uint64) (entries [](*BinlogEntry), err error) {
-	this.currentCoordinates.LogFile = logFile
-	// Start sync with sepcified binlog file and position
-	streamer, err := this.binlogSyncer.StartSync(gomysql.Position{logFile, uint32(startPos)})
-	if err != nil {
-		return entries, err
-	}
-
-	for {
-		ev, err := streamer.GetEvent()
-		if err != nil {
-			return entries, err
-		}
-		this.currentCoordinates.LogPos = int64(ev.Header.LogPos)
-		if rotateEvent, ok := ev.Event.(*replication.RotateEvent); ok {
-			this.currentCoordinates.LogFile = string(rotateEvent.NextLogName)
-			log.Infof("rotate to next log name: %s", rotateEvent.NextLogName)
-		} else if tableMapEvent, ok := ev.Event.(*replication.TableMapEvent); ok {
-			// Actually not being used, since Table is available in RowsEvent.
-			// Keeping this here in case I'm wrong about this. Sometime in the near
-			// future I should remove this.
-			this.tableMap[tableMapEvent.TableID] = string(tableMapEvent.Table)
-		} else if rowsEvent, ok := ev.Event.(*replication.RowsEvent); ok {
-			dml := ToEventDML(ev.Header.EventType.String())
-			if dml == NotDML {
-				return entries, fmt.Errorf("Unknown DML type: %s", ev.Header.EventType.String())
-			}
-			for i, row := range rowsEvent.Rows {
-				if dml == UpdateDML && i%2 == 1 {
-					// An update has two rows (WHERE+SET)
-					// We do both at the same time
-					continue
-				}
-				binlogEntry := NewBinlogEntryAt(this.currentCoordinates)
-				binlogEntry.DmlEvent = NewBinlogDMLEvent(
-					string(rowsEvent.Table.Schema),
-					string(rowsEvent.Table.Table),
-					dml,
-				)
-				switch dml {
-				case InsertDML:
-					{
-						binlogEntry.DmlEvent.NewColumnValues = sql.ToColumnValues(row)
-					}
-				case UpdateDML:
-					{
-						binlogEntry.DmlEvent.WhereColumnValues = sql.ToColumnValues(row)
-						binlogEntry.DmlEvent.NewColumnValues = sql.ToColumnValues(rowsEvent.Rows[i+1])
-					}
-				case DeleteDML:
-					{
-						binlogEntry.DmlEvent.WhereColumnValues = sql.ToColumnValues(row)
-					}
-				}
-			}
-		}
-	}
-	log.Debugf("done")
-	return entries, err
-}

go/cmd/gh-osc/main.go

@@ -35,7 +35,8 @@ func main() {
 	flag.BoolVar(&migrationContext.CountTableRows, "exact-rowcount", false, "actually count table rows as opposed to estimate them (results in more accurate progress estimation)")
 	flag.BoolVar(&migrationContext.AllowedRunningOnMaster, "allow-on-master", false, "allow this migration to run directly on master. Preferably it would run on a replica")
 
-	flag.IntVar(&migrationContext.ChunkSize, "chunk-size", 1000, "amount of rows to handle in each iteration")
+	flag.Int64Var(&migrationContext.ChunkSize, "chunk-size", 1000, "amount of rows to handle in each iteration")
+	flag.StringVar(&migrationContext.ThrottleFlagFile, "throttle-flag-file", "", "operation pauses when this file exists")
 
 	quiet := flag.Bool("quiet", false, "quiet")
 	verbose := flag.Bool("verbose", false, "verbose")

go/logic/applier.go

@@ -8,6 +8,7 @@ package logic
 import (
 	gosql "database/sql"
 	"fmt"
+	"sync/atomic"
 	"time"
 
 	"github.com/github/gh-osc/go/base"
@@ -255,9 +256,9 @@ func (this *Applier) ReadMigrationRangeValues() error {
 	return nil
 }
 
-// IterationIsComplete lets us know when the copy-iteration phase is complete, i.e.
+// __unused_IterationIsComplete lets us know when the copy-iteration phase is complete, i.e.
 // we've exhausted all rows
-func (this *Applier) IterationIsComplete() (bool, error) {
+func (this *Applier) __unused_IterationIsComplete() (bool, error) {
 	if !this.migrationContext.HasMigrationRange() {
 		return false, nil
 	}
@@ -298,7 +299,11 @@ func (this *Applier) IterationIsComplete() (bool, error) {
 	return !moreRowsFound, nil
 }
 
-func (this *Applier) CalculateNextIterationRangeEndValues() error {
+// CalculateNextIterationRangeEndValues reads the next-iteration-range-end unique key values,
+// which will be used for copying the next chunk of rows. Ir returns "false" if there is
+// no further chunk to work through, i.e. we're past the last chunk and are done with
+// itrating the range (and this done with copying row chunks)
+func (this *Applier) CalculateNextIterationRangeEndValues() (hasFurtherRange bool, err error) {
 	this.migrationContext.MigrationIterationRangeMinValues = this.migrationContext.MigrationIterationRangeMaxValues
 	if this.migrationContext.MigrationIterationRangeMinValues == nil {
 		this.migrationContext.MigrationIterationRangeMinValues = this.migrationContext.MigrationRangeMinValues
@@ -313,23 +318,22 @@ func (this *Applier) CalculateNextIterationRangeEndValues() error {
 		fmt.Sprintf("iteration:%d", this.migrationContext.Iteration),
 	)
 	if err != nil {
-		return err
+		return hasFurtherRange, err
 	}
 	rows, err := this.db.Query(query, explodedArgs...)
 	if err != nil {
-		return err
+		return hasFurtherRange, err
 	}
 	iterationRangeMaxValues := sql.NewColumnValues(len(this.migrationContext.UniqueKey.Columns))
-	iterationRangeEndFound := false
 	for rows.Next() {
 		if err = rows.Scan(iterationRangeMaxValues.ValuesPointers...); err != nil {
-			return err
+			return hasFurtherRange, err
 		}
-		iterationRangeEndFound = true
+		hasFurtherRange = true
 	}
-	if !iterationRangeEndFound {
+	if !hasFurtherRange {
 		log.Debugf("Iteration complete: cannot find iteration end")
-		return nil
+		return hasFurtherRange, nil
 	}
 	this.migrationContext.MigrationIterationRangeMaxValues = iterationRangeMaxValues
 	log.Debugf(
@@ -339,10 +343,13 @@ func (this *Applier) CalculateNextIterationRangeEndValues() error {
 		this.migrationContext.Iteration,
 		this.migrationContext.ChunkSize,
 	)
-	return nil
+	return hasFurtherRange, nil
 }
 
-func (this *Applier) ApplyIterationInsertQuery() error {
+func (this *Applier) ApplyIterationInsertQuery() (chunkSize int64, rowsAffected int64, duration time.Duration, err error) {
+	startTime := time.Now()
+	chunkSize = atomic.LoadInt64(&this.migrationContext.ChunkSize)
+
 	query, explodedArgs, err := sql.BuildRangeInsertPreparedQuery(
 		this.migrationContext.DatabaseName,
 		this.migrationContext.OriginalTableName,
@@ -353,44 +360,55 @@ func (this *Applier) ApplyIterationInsertQuery() error {
 		this.migrationContext.MigrationIterationRangeMinValues.AbstractValues(),
 		this.migrationContext.MigrationIterationRangeMaxValues.AbstractValues(),
 		this.migrationContext.Iteration == 0,
+		this.migrationContext.IsTransactionalTable(),
 	)
 	if err != nil {
-		return err
+		return chunkSize, rowsAffected, duration, err
 	}
-	if _, err := sqlutils.Exec(this.db, query, explodedArgs...); err != nil {
-		return err
+	sqlResult, err := sqlutils.Exec(this.db, query, explodedArgs...)
+	if err != nil {
+		return chunkSize, rowsAffected, duration, err
 	}
+	rowsAffected, _ = sqlResult.RowsAffected()
+	duration = time.Now().Sub(startTime)
+	this.WriteChangelog(
+		fmt.Sprintf("copy iteration %d", this.migrationContext.Iteration),
+		fmt.Sprintf("chunk: %d; affected: %d; duration: %d", chunkSize, rowsAffected, duration),
+	)
 	log.Debugf(
 		"Issued INSERT on range: [%s]..[%s]; iteration: %d; chunk-size: %d",
 		this.migrationContext.MigrationIterationRangeMinValues,
 		this.migrationContext.MigrationIterationRangeMaxValues,
 		this.migrationContext.Iteration,
-		this.migrationContext.ChunkSize)
+		chunkSize)
+	return chunkSize, rowsAffected, duration, nil
+}
+
+// LockTables
+func (this *Applier) LockTables() error {
+	query := fmt.Sprintf(`lock /* gh-osc */ tables %s.%s write, %s.%s write, %s.%s write`,
+		sql.EscapeName(this.migrationContext.DatabaseName),
+		sql.EscapeName(this.migrationContext.OriginalTableName),
+		sql.EscapeName(this.migrationContext.DatabaseName),
+		sql.EscapeName(this.migrationContext.GetGhostTableName()),
+		sql.EscapeName(this.migrationContext.DatabaseName),
+		sql.EscapeName(this.migrationContext.GetChangelogTableName()),
+	)
+	log.Infof("Locking tables")
+	if _, err := sqlutils.ExecNoPrepare(this.db, query); err != nil {
+		return err
+	}
+	log.Infof("Tables locked")
 	return nil
 }
 
-// IterateTable
-func (this *Applier) IterateTable(uniqueKey *sql.UniqueKey) error {
-	query, err := sql.BuildUniqueKeyMinValuesPreparedQuery(this.migrationContext.DatabaseName, this.migrationContext.OriginalTableName, uniqueKey.Columns)
-	if err != nil {
+// UnlockTables
+func (this *Applier) UnlockTables() error {
+	query := `unlock /* gh-osc */ tables`
+	log.Infof("Unlocking tables")
+	if _, err := sqlutils.ExecNoPrepare(this.db, query); err != nil {
 		return err
 	}
-	columnValues := sql.NewColumnValues(len(uniqueKey.Columns))
-
-	rows, err := this.db.Query(query)
-	if err != nil {
-		return err
-	}
-	for rows.Next() {
-		if err = rows.Scan(columnValues.ValuesPointers...); err != nil {
-			return err
-		}
-	}
-	log.Debugf("column values: %s", columnValues)
-	query = `insert into test.sample_data_dump (category, ts) values (?, ?)`
-	if _, err := sqlutils.Exec(this.db, query, columnValues.AbstractValues()...); err != nil {
-		return err
-	}
-
+	log.Infof("Tables unlocked")
 	return nil
 }

go/logic/migrator.go

@@ -7,6 +7,7 @@ package logic
 
 import (
 	"fmt"
+	"os"
 	"sync/atomic"
 	"time"
 
@@ -16,6 +17,19 @@ import (
 	"github.com/outbrain/golib/log"
 )
 
+type ChangelogState string
+
+const (
+	TablesInPlace              ChangelogState = "TablesInPlace"
+	AllEventsUpToLockProcessed                = "AllEventsUpToLockProcessed"
+)
+
+type tableWriteFunc func() error
+
+const (
+	applyEventsQueueBuffer = 100
+)
+
 // Migrator is the main schema migration flow manager.
 type Migrator struct {
 	inspector        *Inspector
@@ -24,12 +38,24 @@ type Migrator struct {
 	migrationContext *base.MigrationContext
 
 	tablesInPlace              chan bool
+	rowCopyComplete            chan bool
+	allEventsUpToLockProcessed chan bool
+
+	// copyRowsQueue should not be buffered; if buffered some non-damaging but
+	//  excessive work happens at the end of the iteration as new copy-jobs arrive befroe realizing the copy is complete
+	copyRowsQueue    chan tableWriteFunc
+	applyEventsQueue chan tableWriteFunc
 }
 
 func NewMigrator() *Migrator {
 	migrator := &Migrator{
 		migrationContext:           base.GetMigrationContext(),
 		tablesInPlace:              make(chan bool),
+		rowCopyComplete:            make(chan bool),
+		allEventsUpToLockProcessed: make(chan bool),
+
+		copyRowsQueue:    make(chan tableWriteFunc),
+		applyEventsQueue: make(chan tableWriteFunc, applyEventsQueueBuffer),
 	}
 	migrator.migrationContext.IsThrottled = func() bool {
 		return migrator.shouldThrottle()
@@ -43,6 +69,11 @@ func (this *Migrator) shouldThrottle() bool {
 	shouldThrottle := false
 	if time.Duration(lag) > time.Duration(this.migrationContext.MaxLagMillisecondsThrottleThreshold)*time.Millisecond {
 		shouldThrottle = true
+	} else if this.migrationContext.ThrottleFlagFile != "" {
+		if _, err := os.Stat(this.migrationContext.ThrottleFlagFile); err == nil {
+			//Throttle file defined and exists!
+			shouldThrottle = true
+		}
 	}
 	return shouldThrottle
 }
@@ -62,6 +93,10 @@ func (this *Migrator) onChangelogStateEvent(dmlEvent *binlog.BinlogDMLEvent) (er
 		{
 			this.tablesInPlace <- true
 		}
+	case AllEventsUpToLockProcessed:
+		{
+			this.allEventsUpToLockProcessed <- true
+		}
 	default:
 		{
 			return fmt.Errorf("Unknown changelog state: %+v", changelogState)
@@ -83,12 +118,13 @@ func (this *Migrator) onChangelogHeartbeatEvent(dmlEvent *binlog.BinlogDMLEvent)
 	lag := time.Now().Sub(heartbeatTime)
 
 	atomic.StoreInt64(&this.migrationContext.CurrentLag, int64(lag))
-	log.Debugf("---- - - - - - lag %+v", lag)
 
 	return nil
 }
 
 func (this *Migrator) Migrate() (err error) {
+	this.migrationContext.StartTime = time.Now()
+
 	this.inspector = NewInspector()
 	if err := this.inspector.InitDBConnections(); err != nil {
 		return err
@@ -109,6 +145,97 @@ func (this *Migrator) Migrate() (err error) {
 	}
 	log.Infof("Master found to be %+v", this.migrationContext.MasterConnectionConfig.Key)
 
+	if err := this.initiateStreaming(); err != nil {
+		return err
+	}
+	if err := this.initiateApplier(); err != nil {
+		return err
+	}
+
+	log.Debugf("Waiting for tables to be in place")
+	<-this.tablesInPlace
+	log.Debugf("Tables are in place")
+	// Yay! We now know the Ghost and Changelog tables are good to examine!
+	// When running on replica, this means the replica has those tables. When running
+	// on master this is always true, of course, and yet it also implies this knowledge
+	// is in the binlogs.
+
+	this.migrationContext.UniqueKey = uniqueKeys[0] // TODO. Need to wait on replica till the ghost table exists and get shared keys
+	if err := this.applier.ReadMigrationRangeValues(); err != nil {
+		return err
+	}
+	go this.initiateStatus()
+	go this.executeWriteFuncs()
+	go this.iterateChunks()
+
+	log.Debugf("Operating until row copy is complete")
+	<-this.rowCopyComplete
+	log.Debugf("Row copy complete")
+	this.printStatus()
+
+	throttleMigration(
+		this.migrationContext,
+		func() {
+			log.Debugf("throttling before LOCK TABLES")
+		},
+		nil,
+		func() {
+			log.Debugf("done throttling")
+		},
+	)
+	// TODO retries!!
+	this.applier.LockTables()
+	this.applier.WriteChangelog("state", string(AllEventsUpToLockProcessed))
+	log.Debugf("Waiting for events up to lock")
+	<-this.allEventsUpToLockProcessed
+	log.Debugf("Done waiting for events up to lock")
+	// TODO retries!!
+	this.applier.UnlockTables()
+
+	return nil
+}
+
+func (this *Migrator) initiateStatus() error {
+	this.printStatus()
+	statusTick := time.Tick(1 * time.Second)
+	for range statusTick {
+		go this.printStatus()
+	}
+
+	return nil
+}
+
+func (this *Migrator) printStatus() {
+	elapsedTime := this.migrationContext.ElapsedTime()
+	elapsedSeconds := int64(elapsedTime.Seconds())
+	totalRowsCopied := this.migrationContext.GetTotalRowsCopied()
+	rowsEstimate := this.migrationContext.RowsEstimate
+	progressPct := 100.0 * float64(totalRowsCopied) / float64(rowsEstimate)
+
+	shouldPrintStatus := false
+	if elapsedSeconds <= 60 {
+		shouldPrintStatus = true
+	} else if progressPct >= 99.0 {
+		shouldPrintStatus = true
+	} else if progressPct >= 95.0 {
+		shouldPrintStatus = (elapsedSeconds%5 == 0)
+	} else if elapsedSeconds <= 120 {
+		shouldPrintStatus = (elapsedSeconds%5 == 0)
+	} else {
+		shouldPrintStatus = (elapsedSeconds%30 == 0)
+	}
+	if !shouldPrintStatus {
+		return
+	}
+
+	status := fmt.Sprintf("Copy: %d/%d %.1f%% Backlog: %d/%d Elapsed: %+v(copy), %+v(total) ETA: N/A",
+		totalRowsCopied, rowsEstimate, progressPct,
+		len(this.applyEventsQueue), cap(this.applyEventsQueue),
+		this.migrationContext.ElapsedRowCopyTime(), elapsedTime)
+	fmt.Println(status)
+}
+
+func (this *Migrator) initiateStreaming() error {
 	this.eventsStreamer = NewEventsStreamer()
 	if err := this.eventsStreamer.InitDBConnections(); err != nil {
 		return err
@@ -133,7 +260,10 @@ func (this *Migrator) Migrate() (err error) {
 		log.Debugf("Beginning streaming")
 		this.eventsStreamer.StreamEvents(func() bool { return this.canStopStreaming() })
 	}()
+	return nil
+}
 
+func (this *Migrator) initiateApplier() error {
 	this.applier = NewApplier()
 	if err := this.applier.InitDBConnections(); err != nil {
 		return err
@@ -153,48 +283,73 @@ func (this *Migrator) Migrate() (err error) {
 
 	this.applier.WriteChangelog("state", string(TablesInPlace))
 	this.applier.InitiateHeartbeat()
-
-	<-this.tablesInPlace
-	// Yay! We now know the Ghost and Changelog tables are good to examine!
-	// When running on replica, this means the replica has those tables. When running
-	// on master this is always true, of course, and yet it also implies this knowledge
-	// is in the binlogs.
-
-	this.migrationContext.UniqueKey = uniqueKeys[0] // TODO. Need to wait on replica till the ghost table exists and get shared keys
-	if err := this.applier.ReadMigrationRangeValues(); err != nil {
-		return err
+	return nil
 }
+
+func (this *Migrator) iterateChunks() error {
+	this.migrationContext.RowCopyStartTime = time.Now()
+	terminateRowIteration := func(err error) error {
+		this.rowCopyComplete <- true
+		return log.Errore(err)
+	}
+	for {
+		copyRowsFunc := func() error {
+			hasFurtherRange, err := this.applier.CalculateNextIterationRangeEndValues()
+			if err != nil {
+				return terminateRowIteration(err)
+			}
+			if !hasFurtherRange {
+				return terminateRowIteration(nil)
+			}
+			_, rowsAffected, _, err := this.applier.ApplyIterationInsertQuery()
+			if err != nil {
+				return terminateRowIteration(err)
+			}
+			atomic.AddInt64(&this.migrationContext.TotalRowsCopied, rowsAffected)
+			this.migrationContext.Iteration++
+			return nil
+		}
+		this.copyRowsQueue <- copyRowsFunc
+	}
+	return nil
+}
+
+func (this *Migrator) executeWriteFuncs() error {
 	for {
 		throttleMigration(
 			this.migrationContext,
 			func() {
-				log.Debugf("throttling rowcopy")
+				log.Debugf("throttling writes")
 			},
 			nil,
 			func() {
-				log.Debugf("done throttling rowcopy")
+				log.Debugf("done throttling writes")
 			},
 		)
-		isComplete, err := this.applier.IterationIsComplete()
-		if err != nil {
-			return err
+		// We give higher priority to event processing, then secondary priority to
+		// rowcopy
+		select {
+		case applyEventFunc := <-this.applyEventsQueue:
+			{
+				retryOperation(applyEventFunc, this.migrationContext.MaxRetries())
+			}
+		default:
+			{
+				select {
+				case copyRowsFunc := <-this.copyRowsQueue:
+					{
+						retryOperation(copyRowsFunc, this.migrationContext.MaxRetries())
+					}
+				default:
+					{
+						// Hmmmmm... nothing in the queue; no events, but also no row copy.
+						// This is possible upon load. Let's just sleep it over.
+						log.Debugf("Getting nothing in the write queue. Sleeping...")
+						time.Sleep(time.Second)
 					}
-		if isComplete {
-			break
 				}
-		if err = this.applier.CalculateNextIterationRangeEndValues(); err != nil {
-			return err
 			}
-		if err = this.applier.ApplyIterationInsertQuery(); err != nil {
-			return err
 		}
-		this.migrationContext.Iteration++
 	}
-	// temporary wait:
-	heartbeatTick := time.Tick(10 * time.Second)
-	for range heartbeatTick {
-		return nil
-	}
-
 	return nil
 }

go/sql/builder.go

@@ -128,7 +128,7 @@ func BuildRangePreparedComparison(columns []string, args []interface{}, comparis
 	return BuildRangeComparison(columns, values, args, comparisonSign)
 }
 
-func BuildRangeInsertQuery(databaseName, originalTableName, ghostTableName string, sharedColumns []string, uniqueKey string, uniqueKeyColumns, rangeStartValues, rangeEndValues []string, rangeStartArgs, rangeEndArgs []interface{}, includeRangeStartValues bool) (result string, explodedArgs []interface{}, err error) {
+func BuildRangeInsertQuery(databaseName, originalTableName, ghostTableName string, sharedColumns []string, uniqueKey string, uniqueKeyColumns, rangeStartValues, rangeEndValues []string, rangeStartArgs, rangeEndArgs []interface{}, includeRangeStartValues bool, transactionalTable bool) (result string, explodedArgs []interface{}, err error) {
 	if len(sharedColumns) == 0 {
 		return "", explodedArgs, fmt.Errorf("Got 0 shared columns in BuildRangeInsertQuery")
 	}
@@ -155,28 +155,32 @@ func BuildRangeInsertQuery(databaseName, originalTableName, ghostTableName strin
 		return "", explodedArgs, err
 	}
 	explodedArgs = append(explodedArgs, rangeExplodedArgs...)
+	transactionalClause := ""
+	if transactionalTable {
+		transactionalClause = "lock in share mode"
+	}
 	result = fmt.Sprintf(`
       insert /* gh-osc %s.%s */ ignore into %s.%s (%s)
       (select %s from %s.%s force index (%s)
-        where (%s and %s)
+        where (%s and %s) %s
       )
     `, databaseName, originalTableName, databaseName, ghostTableName, sharedColumnsListing,
 		sharedColumnsListing, databaseName, originalTableName, uniqueKey,
-		rangeStartComparison, rangeEndComparison)
+		rangeStartComparison, rangeEndComparison, transactionalClause)
 	return result, explodedArgs, nil
 }
 
-func BuildRangeInsertPreparedQuery(databaseName, originalTableName, ghostTableName string, sharedColumns []string, uniqueKey string, uniqueKeyColumns []string, rangeStartArgs, rangeEndArgs []interface{}, includeRangeStartValues bool) (result string, explodedArgs []interface{}, err error) {
+func BuildRangeInsertPreparedQuery(databaseName, originalTableName, ghostTableName string, sharedColumns []string, uniqueKey string, uniqueKeyColumns []string, rangeStartArgs, rangeEndArgs []interface{}, includeRangeStartValues bool, transactionalTable bool) (result string, explodedArgs []interface{}, err error) {
 	rangeStartValues := make([]string, len(uniqueKeyColumns), len(uniqueKeyColumns))
 	rangeEndValues := make([]string, len(uniqueKeyColumns), len(uniqueKeyColumns))
 	for i := range uniqueKeyColumns {
 		rangeStartValues[i] = "?"
 		rangeEndValues[i] = "?"
 	}
-	return BuildRangeInsertQuery(databaseName, originalTableName, ghostTableName, sharedColumns, uniqueKey, uniqueKeyColumns, rangeStartValues, rangeEndValues, rangeStartArgs, rangeEndArgs, includeRangeStartValues)
+	return BuildRangeInsertQuery(databaseName, originalTableName, ghostTableName, sharedColumns, uniqueKey, uniqueKeyColumns, rangeStartValues, rangeEndValues, rangeStartArgs, rangeEndArgs, includeRangeStartValues, transactionalTable)
 }
 
-func BuildUniqueKeyRangeEndPreparedQuery(databaseName, tableName string, uniqueKeyColumns []string, rangeStartArgs, rangeEndArgs []interface{}, chunkSize int, hint string) (result string, explodedArgs []interface{}, err error) {
+func BuildUniqueKeyRangeEndPreparedQuery(databaseName, tableName string, uniqueKeyColumns []string, rangeStartArgs, rangeEndArgs []interface{}, chunkSize int64, hint string) (result string, explodedArgs []interface{}, err error) {
 	if len(uniqueKeyColumns) == 0 {
 		return "", explodedArgs, fmt.Errorf("Got 0 columns in BuildUniqueKeyRangeEndPreparedQuery")
 	}