func (d *ddl) backfillColumn(ctx context.Context, t table.Table, columnInfo *model.ColumnInfo, handles []int64, reorgInfo *reorgInfo) error {
var defaultVal types.Datum
var err error
if columnInfo.DefaultValue != nil {
defaultVal, _, err = table.GetColDefaultValue(ctx, columnInfo)
if err != nil {
return errors.Trace(err)
}
} else if mysql.HasNotNullFlag(columnInfo.Flag) {
defaultVal = table.GetZeroValue(columnInfo)
}
colMap := make(map[int64]*types.FieldType)
for _, col := range t.Meta().Columns {
colMap[col.ID] = &col.FieldType
}
var endIdx int
for len(handles) > 0 {
if len(handles) >= defaultSmallBatchCnt {
endIdx = defaultSmallBatchCnt
} else {
endIdx = len(handles)
}
err = kv.RunInNewTxn(d.store, true, func(txn kv.Transaction) error {
if err := d.isReorgRunnable(txn, ddlJobFlag); err != nil {
return errors.Trace(err)
}
nextHandle, err1 := d.backfillColumnInTxn(t, columnInfo.ID, handles[:endIdx], colMap, defaultVal, txn)
if err1 != nil {
return errors.Trace(err1)
}
return errors.Trace(reorgInfo.UpdateHandle(txn, nextHandle))
})
if err != nil {
return errors.Trace(err)
}
handles = handles[endIdx:]
}
return nil
}
func (d *ddl) backfillColumnData(t table.Table, columnInfo *model.ColumnInfo, handles []int64, reorgInfo *reorgInfo) error {
var (
defaultVal types.Datum
err error
)
if columnInfo.DefaultValue != nil {
defaultVal, _, err = table.GetColDefaultValue(nil, columnInfo)
if err != nil {
return errors.Trace(err)
}
} else if mysql.HasNotNullFlag(columnInfo.Flag) {
defaultVal = table.GetZeroValue(columnInfo)
}
colMap := make(map[int64]*types.FieldType)
for _, col := range t.Meta().Columns {
colMap[col.ID] = &col.FieldType
}
for _, handle := range handles {
log.Info("[ddl] backfill column...", handle)
err := kv.RunInNewTxn(d.store, true, func(txn kv.Transaction) error {
if err := d.isReorgRunnable(txn); err != nil {
return errors.Trace(err)
}
rowKey := t.RecordKey(handle)
rowVal, err := txn.Get(rowKey)
if terror.ErrorEqual(err, kv.ErrNotExist) {
// If row doesn't exist, skip it.
return nil
}
if err != nil {
return errors.Trace(err)
}
rowColumns, err := tablecodec.DecodeRow(rowVal, colMap)
if err != nil {
return errors.Trace(err)
}
if _, ok := rowColumns[columnInfo.ID]; ok {
// The column is already added by update or insert statement, skip it.
return nil
}
newColumnIDs := make([]int64, 0, len(rowColumns)+1)
newRow := make([]types.Datum, 0, len(rowColumns)+1)
for colID, val := range rowColumns {
newColumnIDs = append(newColumnIDs, colID)
newRow = append(newRow, val)
}
newColumnIDs = append(newColumnIDs, columnInfo.ID)
newRow = append(newRow, defaultVal)
newRowVal, err := tablecodec.EncodeRow(newRow, newColumnIDs)
if err != nil {
return errors.Trace(err)
}
err = txn.Set(rowKey, newRowVal)
if err != nil {
return errors.Trace(err)
}
return errors.Trace(reorgInfo.UpdateHandle(txn, handle))
})
if err != nil {
return errors.Trace(err)
}
}
return nil
}