2020-02-16 标签:sql,语句,技巧,按月,统计,数据,结构,如下,qty,date,13,2005,01,17,15,19,25,105

表结构如下: qty date ---------------------------------------------- 13 2005/01/17 15 2005/01/19 3 2005/01/25 105 2005/01/27 1 2005/01/31 352 2005/02/03 12