需求背景
群组表
group
聊天记录表
按月分表,如
chat_message_2015_04
chat_message_2015_05
chat_message_2015_06
表结构
chatTime //message时间
groupID //组ID
需求描述
- 给定一个时间段,如当天/最近7天/当月/2015-04-12 ~ 2015-06-17,统计给定时间段内各个group的message数量
- 按照统计出来的message数量,对group进行排序与分页输出
回复内容:
需求背景
群组表
group
聊天记录表
按月分表,如
chat_message_2015_04
chat_message_2015_05
chat_message_2015_06
表结构
chatTime //message时间
groupID //组ID
需求描述
- 给定一个时间段,如当天/最近7天/当月/2015-04-12 ~ 2015-06-17,统计给定时间段内各个group的message数量
- 按照统计出来的message数量,对group进行排序与分页输出
1、UNION
2、若是innodb分表,则可以用merge处理。
直接搞一张专门针对统计数据用的汇总表
如果可能的话,不要采用分表的设计,采用表分区,这样就对于查询就不需要特殊处理了。规划好索引,性能应该不会有问题。

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