code: func (w *worker) handleUpdateJobError(t *meta.Meta, job *model.Job, err error) error {
  	if err == nil {
  		return nil
  	}
  	if kv.ErrEntryTooLarge.Equal(err) {
  		logutil.Logger(w.logCtx).Warn("[ddl] update DDL job failed", zap.String("job", job.String()), zap.Error(err))
  		// Reduce this txn entry size.
  		job.BinlogInfo.Clean()
  		job.Error = toTError(err)
  		job.SchemaState = model.StateNone
  		job.State = model.JobStateCancelled
  		err = w.finishDDLJob(t, job)
  	}
  	return errors.Trace(err)
  }
docs: // handleUpdateJobError handles the too large DDL job.