- 【TiDB 版本】:3.0.7
- 【问题描述】:
执行sql语句:
select from_unixtime(a.created_time,‘%Y-%m-%d’)
from yop_user a
where a.username = ‘test’
UNION
select from_unixtime(a.created_time,‘%Y-%m-%d’)
from yop_user a
where a.username = ‘test’;
执行sql语句:
select from_unixtime(a.created_time,‘%Y-%m-%d’)
from yop_user a
where a.username = ‘test’
UNION
select from_unixtime(a.created_time,‘%Y-%m-%d’)
from yop_user a
where a.username = ‘test’;
麻烦加以描述,如果和预期不符合,麻烦提供下面 union 操作拆解为 2 个 SQL 结果验证是否符合预期。
两条sql是一样的,截图中第一条是单条sql执行结果
麻烦发一下两次 SQL 分别结果截图,以及 explain analyze 截图。
select from_unixtime(a.created_time,’%Y-%m-%d’) from yop_user a where a.username = ‘test’ UNION select from_unixtime(a.created_time,’%Y-%m-%d’) from yop_user a where a.username = ‘test’;
select from_unixtime(a.created_time,’%Y-%m-%d’) from yop_user a where a.username = ‘test’
explain analyze select from_unixtime(a.created_time,’%Y-%m-%d’) from yop_user a where a.username = ‘test’ UNION select from_unixtime(a.created_time,’%Y-%m-%d’) from yop_user a where a.username = ‘test’;
explain select from_unixtime(a.created_time,’%Y-%m-%d’) from yop_user a where a.username = ‘test’
稍等,确认一下