restore: don't restore auto id if the table doesn't has it. (#420)

* restore: don't restore auto id if the table doesn't has it.

* restore: fix some bugs

* backup: don't alloc auto ID if the table doesn't need it

* restore: remove `table.NeedRebaseAutoID`

pkg/backup/client.go

@@ -268,8 +268,8 @@ func BuildBackupRangeAndSchema(
  switch {
  case tableInfo.IsSequence():
  globalAutoID, err = seqAlloc.NextGlobalAutoID(tableInfo.ID)
- case tableInfo.IsView():
- // no auto ID for views.
+ case tableInfo.IsView() || !utils.NeedAutoID(tableInfo):
+ // no auto ID for views or table without either rowID nor auto_increment ID.
  default:
  globalAutoID, err = idAlloc.NextGlobalAutoID(tableInfo.ID)
  }

pkg/restore/db.go

@@ -150,6 +150,7 @@ func (db *DB) CreateTable(ctx context.Context, table *utils.Table) error {
  }
  }
  restoreMetaSQL = fmt.Sprintf(setValFormat, table.Info.AutoIncID)
+ err = db.se.Execute(ctx, restoreMetaSQL)
  } else {
  var alterAutoIncIDFormat string
  switch {
@@ -163,9 +164,11 @@ func (db *DB) CreateTable(ctx context.Context, table *utils.Table) error {
  utils.EncloseName(table.Db.Name.O),
  utils.EncloseName(table.Info.Name.O),
  table.Info.AutoIncID)
+ if utils.NeedAutoID(table.Info) {
+ err = db.se.Execute(ctx, restoreMetaSQL)
+ }
  }
 
- err = db.se.Execute(ctx, restoreMetaSQL)
  if err != nil {
  log.Error("restore meta sql failed",
  zap.String("query", restoreMetaSQL),

pkg/utils/schema.go

@@ -40,6 +40,13 @@ func (tbl *Table) NoChecksum() bool {
  return tbl.Crc64Xor == 0 && tbl.TotalKvs == 0 && tbl.TotalBytes == 0
 }
 
+// NeedAutoID checks whether the table needs backing up with an autoid.
+func NeedAutoID(tblInfo *model.TableInfo) bool {
+ hasRowID := !tblInfo.PKIsHandle && !tblInfo.IsCommonHandle
+ hasAutoIncID := tblInfo.GetAutoIncrementColInfo() != nil
+ return hasRowID || hasAutoIncID
+}
+
 // Database wraps the schema and tables of a database.
 type Database struct {
  Info *model.DBInfo