utils.py 文件源码

def __delitem__(self, key):
    if self.read_only:
      return
    query = """DELETE FROM {tb} WHERE {cond};"""
    if isinstance(key, (tuple, list, Iterator, np.ndarray)):
      key = [str(k) for k in key]
    else:
      key = [str(key)]
    # ====== check if key in cache ====== #
    db_key = []
    for k in key:
      if k in self.current_cache:
        del self.current_cache[k]
      else:
        db_key.append(k)
    # ====== remove key from db ====== #
    self.cursor.execute(
        query.format(tb=self._current_table,
                     cond='key IN ("%s")' % ', '.join(db_key)))
    self.connection.commit()