code: func (h *BindHandle) AddDropInvalidBindTask(invalidBindRecord *BindRecord) {
  	key := invalidBindRecord.OriginalSQL + ":" + invalidBindRecord.Db
  	if _, ok := h.invalidBindRecordMap.Value.Load().(map[string]*invalidBindRecordMap)[key]; ok {
  		return
  	}
  	h.invalidBindRecordMap.Lock()
  	defer h.invalidBindRecordMap.Unlock()
  	if _, ok := h.invalidBindRecordMap.Value.Load().(map[string]*invalidBindRecordMap)[key]; ok {
  		return
  	}
  	newMap := copyInvalidBindRecordMap(h.invalidBindRecordMap.Value.Load().(map[string]*invalidBindRecordMap))
  	newMap[key] = &invalidBindRecordMap{
  		bindRecord: invalidBindRecord,
  	}
  	h.invalidBindRecordMap.Store(newMap)
  }
docs: // AddDropInvalidBindTask add bindRecord to invalidBindRecordMap when the bindRecord need to be deleted.