Question

我的Oracle数据库中有一个名为ID的列，它是一个字符串，其值为859188_1,859188_2,859188_3，...，859188_n。＆＃39; _＆＃39;之后的值是批号，即1,2,3，...，n。我需要根据此批号选择最小ID。这里的最小值是859188_1。

Answer 1

...试

 select id
 from yourTable
 where to_number(regexp_substr(ID, '[^_]+$')) =
   (select min(to_number(regexp_substr(t2.ID, '[^_]+$')))
    from yourTable t2
   )

Answer 2

您需要根据 _之后部分选择最小值。

如果 - 在您的示例中 - 前六个字符都相同，您只需执行以下操作：

select min(id) keep (dense_rank first order by length(id) asc, id asc) as min_id from t;

Answer 3

也许是这样的......

with
     inputs ( id ) as (
       select '100_1'  from dual union all
       select '100_3'  from dual union all
       select '100_12' from dual union all
       select '101_3'  from dual union all
       select '101_5'  from dual union all
       select '101_9'  from dual
     )
-- end of test data; solution (SQL query) begins below this line
select   min(id) keep (dense_rank first 
                       order by to_number(substr(id, instr(id, '_') + 1))) as id
from     inputs
group by substr(id, 1, instr(id, '_') - 1)
;

ID
-----
100_1
101_3

Oracle SQL查询从包含批次编号的字符串中查找最小值

3 个答案: