{"id":658,"date":"2018-05-30T12:51:50","date_gmt":"2018-05-30T04:51:50","guid":{"rendered":"https:\/\/blog.freesilo.com\/?p=658"},"modified":"2018-05-30T12:51:50","modified_gmt":"2018-05-30T04:51:50","slug":"sql%e8%af%ad%e5%8f%a5%e5%8e%bb%e6%8e%89%e9%87%8d%e5%a4%8d%e8%ae%b0%e5%bd%95%ef%bc%8c%e8%8e%b7%e5%8f%96%e9%87%8d%e5%a4%8d%e8%ae%b0%e5%bd%95","status":"publish","type":"post","link":"https:\/\/freesilo.com\/?p=658","title":{"rendered":"SQL\u8bed\u53e5\u53bb\u6389\u91cd\u590d\u8bb0\u5f55\uff0c\u83b7\u53d6\u91cd\u590d\u8bb0\u5f55"},"content":{"rendered":"<pre class=\"brush: sql; title: ; notranslate\" title=\"\">\r\n--\u6309\u7167\u67d0\u51e0\u4e2a\u5b57\u6bb5\u540d\u79f0\u67e5\u627e\u8868\u4e2d\u5b58\u5728\u8fd9\u51e0\u4e2a\u5b57\u6bb5\u7684\u91cd\u590d\u6570\u636e\u5e76\u6309\u7167\u63d2\u5165\u7684\u65f6\u95f4\u5148\u540e\u8fdb\u884c\u5220\u9664\uff0c\r\n\u6761\u4ef6\u53d6\u51b3\u4e8eorder by \u548crow_num\r\n--\u65b9\u6cd5\u4e00\u6309\u7167\u591a\u6761\u4ef6\u91cd\u590d\u5904\u7406\uff1a\r\ndelete tmp from(\r\nselect row_num=row_number() over(partition by \u5b57\u6bb5\uff0c\u5b57\u6bb5 order by \u65f6\u95f4 desc)\r\n    from \u8868 where \u65f6\u95f4&gt; getdate()-1\r\n) tmp\r\nwhere row_num &gt; 1 \r\n\r\n--\u65b9\u6cd5\u4e8c\u6309\u7167\u5355\u4e00\u6761\u4ef6\u8fdb\u884c\u53bb\u91cd\uff1a\r\ndelete from \u8868 where \u4e3b\u952eID not in(\r\nselect max(\u4e3b\u952eID) from \u8868 \r\ngroup by \u9700\u8981\u53bb\u91cd\u7684\u5b57\u6bb5 \r\nhaving count(\u9700\u8981\u53bb\u91cd\u7684\u5b57\u6bb5)&gt;=1\r\n)\r\n--\u6ce8\u610f\uff1a\u4e3a\u63d0\u9ad8\u6548\u7387\u5982\u4e0a\u4e24\u4e2a\u65b9\u6cd5\u90fd\u53ef\u4ee5\u4f7f\u7528\u4e34\u65f6\u8868\uff0cnot in\u4e2d\u7684\u8868\u53ef\u4ee5\u5148\u63d0\u53d6\u4e34\u65f6\u8868#tmp\uff0c\r\n--\u7136\u540e\u91c7\u7528not exists\u6765\u6267\u884c\uff0c\u4e3a\u907f\u514d\u6570\u91cf\u8fc7\u5927\uff0c\u53ef\u6279\u91cf\u7528Top\u63a7\u5236\u5220\u9664\u91cf\r\ndelete top(2) from \u8868 \r\n        where  not exists (select \u4e3b\u952eID\r\n  from #tmp where #tmp.\u4e3b\u952eID=\u8868.\u4e3b\u952eID) \r\n\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>&#8211;\u6309\u7167\u67d0\u51e0\u4e2a\u5b57\u6bb5\u540d\u79f0\u67e5\u627e\u8868\u4e2d\u5b58\u5728\u8fd9\u51e0\u4e2a\u5b57\u6bb5\u7684\u91cd\u590d\u6570\u636e\u5e76\u6309\u7167\u63d2\u5165\u7684\u65f6\u95f4\u5148\u540e\u8fdb\u884c\u5220&#8230;<br \/><a class=\"read-more-button\" href=\"https:\/\/freesilo.com\/?p=658\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":["post-658","post","type-post","status-publish","format-standard","hentry","category-sql"],"_links":{"self":[{"href":"https:\/\/freesilo.com\/index.php?rest_route=\/wp\/v2\/posts\/658","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/freesilo.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/freesilo.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/freesilo.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/freesilo.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=658"}],"version-history":[{"count":3,"href":"https:\/\/freesilo.com\/index.php?rest_route=\/wp\/v2\/posts\/658\/revisions"}],"predecessor-version":[{"id":664,"href":"https:\/\/freesilo.com\/index.php?rest_route=\/wp\/v2\/posts\/658\/revisions\/664"}],"wp:attachment":[{"href":"https:\/\/freesilo.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=658"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/freesilo.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=658"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/freesilo.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=658"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}