mysql - 如何在mysql中两次选择1个表中的同一列

Question

如何仅使用 1 个表选择 1 列两次，问题是我必须将 1 列分成 2 个返回

例如:表日志

TIMELOGS   11:00 , 12:12 , 13:00 , 17:01 , 17:05 , 17:10

TIMEMODE     0    ,   0     ,  0    ,   1    ,   1     ,   1

输出应该是

IN   11:00 , 12:12 , 13:00

OUT   17:01, 17:05 , 17:10

如何将这些组合到查询中

Select TIMELOGS as IN FROM table_logs where TIMEMODE = 0;

和

Select TIMELOGS as OUT FROM table_logs where TIMEMODE = 1; 

Answer 1

如果我理解正确的话，您想要枚举 0 和 1，然后按其分组:

select max(case when mode = 0 then time end),
       max(case when mode = 1 then time end)
from (select l.*,
             (@rn := if(@m = mode, @rn + 1,
                        if(@m := mode, 1, 1)
                       )
             ) as rn
      from logs l cross join
           (select @rn := 0, @m := -1) params
      order by mode, time
     ) l
group by rn;