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标题: mysql 使用distinct查询数据为零 [打印本页]

作者: zhangdong    时间: 2015-11-5 20:03
标题: mysql 使用distinct查询数据为零
mysql 使用distinct查询数据为零

症状:
mysql> select count(distinct mac) from tvservice.mtv_account where openTime between '2015-10-29 00:00:00' and '2015-10-29 23:59:59';
+---------------------+
| count(distinct mac) |
+---------------------+
|                   0 |
+---------------------+
1 row in set (0.42 sec)


原因:是distinct bug的问题

帖子:http://dinglin.iteye.com/blog/1982176

解决方法:
tmp_table_size=1024M
max_heap_table_size=512M


帖子:http://blog.csdn.net/a351945755/article/details/23457389





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