Question

我有一张表，上面有这样的数据：

Id     | Version | isLive
-------+---------+-------
comp1  |   2     | true     
comp1  |   3     | true     
comp1  |   4     | false    
comp1  |   1     | true      
comp2  |   4     | true      
comp2  |   1     | false

我想获取每个ID具有最高版本号的行。因此，每个ID只能有一行。

select id 
from mytable 
group by id

这将随机返回数据。

Answer 1

来自here

SELECT * FROM (SELECT * FROM MyTbl ORDER BY version ) WHERE rownum = 1;

Answer 2

这是您想要的吗？

         select id,max(distinct version) from 
         mytable 
        group by id order by id

Answer 3

如何？

SQL> with test (id, version, islive) as
  2    (select 'comp1', 2, 'true'  from dual union all
  3     select 'comp1', 3, 'true'  from dual union all
  4     select 'comp1', 4, 'false' from dual union all
  5     select 'comp1', 1, 'true'  from dual union all
  6     select 'comp2', 4, 'true'  from dual union all
  7     select 'comp2', 1, 'false' from dual
  8    )
  9  select id, version, islive
 10  from (select id, version, islive,
 11          row_number() over (partition by id order by version desc) rn
 12        from test
 13       )
 14  where rn = 1;

ID       VERSION ISLIV
----- ---------- -----
comp1          4 false
comp2          4 true

SQL>

SQL从具有最高版本值的行中获取数据

3 个答案: