Question

我需要进行一个查询，根据最后和最后一个搜索时间输出数据。让我解释一下表格：

id  key         comp    timestamp
1   keyword1    comp1   11-04-2015 23:56
2   keyword2    comp3   12-04-2015 23:56
3   keyword1    comp2   12-04-2015 00:56
4   keyword3    comp4   11-04-2015 23:56
5   keyword3    comp6   11-04-2015 23:56

现在输出应为：

keyword1    comp1   11-04-2015 23:56    comp2   12-04-2015 00:56

意味着我需要显示关键字1的最后搜索到的和最后搜索到的第二个comp名称...我真的很无奈在这种情况下如何继续....任何人都可以指导我这个......

Answer 1

select  r1.key
,       r1.comp
,       r1.timestamp
,       r2.key
,       r2.comp
,       r2.timestamp
from    (
        select  *
        from    YourTable
        where   `key` = 'keyword1'
        order by
                timestamp desc
        limit   1 -- First row
        ) r1
left join
        (
        select  *
        from    YourTable
        where   `key` = 'keyword1'
        order by
                timestamp desc
        limit   1, 1 -- Skip 1, take 1 --> second row
        ) r2
on      1=1

See it working at SQL Fiddle.

带有时间戳分组的mysql查询

1 个答案: