2. 接1。第一个参数可以是year, quater, month, week, day, hour, minute, second, millisecond, 也可以简写成y, m等 3. Click house中uniqExact和distinct功能相同 4. 对df进行遍历:iterrows() 是将df迭代为(index, series)对; itertuples() 是将df迭代为元组;iteritems() 是将df迭代为(列名,ser ...