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  • 关于优化sql查询的一个方法。

    select * from gmvcsbase.base_file file,gmvcsbase.base_user user,gmvcsbase.base_department dep,gmvcsbase.base_workstation work
    where file.police_id=user.police_id and user.dep_code=dep.code and file.workstation_sid=work.sid and file.capture_time>='2013-10-30'
    AND file.capture_time<='2014-03-19 23:59:59' ORDER BY file.id DESC LIMIT 0,20

    select * from gmvcsbase.base_file file,gmvcsbase.base_user user,gmvcsbase.base_department dep, gmvcsbase.base_workstation work,
    (
    select file.id
    from gmvcsbase.base_file file,gmvcsbase.base_user user,gmvcsbase.base_department dep, gmvcsbase.base_workstation work
    where file.police_id=user.police_id and user.dep_code=dep.code and file.workstation_sid=work.sid and file.capture_time>='2013-11-30'
    AND file.capture_time<='2014-03-19 23:59:59'
    ORDER BY file.import_time DESC LIMIT 0,20
    ) as t
    where file.police_id=user.police_id and user.dep_code=dep.code and file.workstation_sid=work.sid and file.id=t.id
    ORDER BY file.import_time DESC

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  • 原文地址:https://www.cnblogs.com/zenghansen/p/3611375.html
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