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  • mysql去除重复查询的SQL语句基本思路

    SELECT R.* FROM trans_flow  R, (SELECT order_no, MAX(status_time) AS status_time FROM trans_flow GROUP BY order_no) S 
    WHERE R.order_no = S.order_no AND R.status_time = S.status_time 
    ORDER BY R.status_time DESC 
    
    SELECT a.order_no,a.mem_no,c.card_no,c.card_holder,c.bank_name,c.branch_bank_name,a.flag, a.income_type_txt,a.amt,a.create_time FROM account_log a  
    JOIN (SELECT b.*,MAX(id) FROM account b GROUP BY b.mem_no) c 
    ON DATE_ADD(a.create_time, INTERVAL 7 DAY) < NOW() AND a.`mem_no` = c.mem_no  
    ORDER BY a.id DESC 

    解决思路:
    结构如下:
    type name guest       date
    1   aa       sa           20131101
    1   bb      dsf           20131102
    1   aa      wew         20131103
    我想按照name分组,按照date降序排列,希望的结果如下:
    type name guest   date
    1   aa       wew     20131103
    1   bb       dsf       20131102

    select R.* from tab  R, (select name, max(date) from tab group by name) S
    where R.name=S.name and R.date=S.date
    order by R.date desc

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  • 原文地址:https://www.cnblogs.com/simpledev/p/3966975.html
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