{"id":595,"date":"2020-09-21T11:56:12","date_gmt":"2020-09-21T03:56:12","guid":{"rendered":"http:\/\/pony.hk\/?p=595"},"modified":"2020-09-25T10:30:35","modified_gmt":"2020-09-25T02:30:35","slug":"mysql%e6%8c%89a-b-c-d%e5%9b%9b%e4%b8%aa%e5%ad%97%e6%ae%b5%e4%b8%ad%e7%9a%84%e6%9c%80%e5%b0%8f%e6%ad%a3%e6%95%b4%e6%95%b0%ef%bc%8c%e7%94%b1%e5%b0%8f%e5%88%b0%e5%a4%a7%e8%bf%9b%e8%a1%8c%e6%8e%92","status":"publish","type":"post","link":"https:\/\/lnmp.ivan.xin\/?p=595","title":{"rendered":"mysql\u6309a b c d\u56db\u4e2a\u5b57\u6bb5\u4e2d\u7684\u6700\u5c0f\u6b63\u6574\u6570\uff0c\u7531\u5c0f\u5230\u5927\u8fdb\u884c\u6392\u5e8f"},"content":{"rendered":"<p>\u9700\u6c42\uff1a\u7b2c\u4e00\u5f20\u56fe\u662f\u539f\u59cb\u6570\u636e\uff0c\u7b2c\u4e8c\u5f20\u56fe\u4e2d\u7684\u987a\u5e8f\u662f\u6309\u6211\u7684\u9700\u6c42\u7684\u6392\u5217\u7ed3\u679c\u3002\u597d\u6bd4\u865a\u62df\u51fa\u6765\u65b0\u7684\u4e00\u5217 e\uff0ce\u7684\u503c\u662fabcd\u4e2d\u7684\u6700\u5c0f\u6b63\u6574\u6570\uff0c\u7136\u540e\u6309e\u7684\u5927\u5c0f\u6392\u5e8f\u3002<\/p>\n<p><a href=\"http:\/\/pony.hk\/files\/2020\/09\/1.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-596\" src=\"http:\/\/pony.hk\/files\/2020\/09\/1-300x91.png\" alt=\"\" width=\"300\" height=\"91\" srcset=\"https:\/\/lnmp.ivan.xin\/files\/2020\/09\/1-300x91.png 300w, https:\/\/lnmp.ivan.xin\/files\/2020\/09\/1.png 361w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p><a href=\"http:\/\/pony.hk\/files\/2020\/09\/2.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-597\" src=\"http:\/\/pony.hk\/files\/2020\/09\/2-300x76.png\" alt=\"\" width=\"300\" height=\"76\" srcset=\"https:\/\/lnmp.ivan.xin\/files\/2020\/09\/2-300x76.png 300w, https:\/\/lnmp.ivan.xin\/files\/2020\/09\/2.png 433w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p>mysql\u7684\u8bed\u53e5\uff1a<\/p>\n<p>\u7b2c\u4e00\u79cd\uff1a<\/p>\n<blockquote><p>select *<br \/>\nfrom t1 a<br \/>\nleft join<br \/>\n(<br \/>\nselect id, min(a) minnum from<br \/>\n(select id, a a from t1 where a&gt;0<br \/>\nunion all<br \/>\nselect id, b a from t1 where b&gt;0<br \/>\nunion all<br \/>\nselect id, c a from t1 where c&gt;0<br \/>\nunion all<br \/>\nselect id, d a from t1 where d&gt;0<br \/>\n) t1<br \/>\ngroup by t1.id<br \/>\n) b<br \/>\non a.id=b.id<br \/>\norder by b.minnum asc, b.id asc;<\/p><\/blockquote>\n<p>\u7b2c\u4e8c\u79cd\uff0c\u6548\u7387\u66f4\u9ad8\uff1a<\/p>\n<blockquote><p>select a,b,c,d,least(if( a&gt;0, a ,100000000),if(b&gt;0,b,100000000),if(c&gt;0,c,100000000),if(d&gt;0,d,100000000)) as minVal from t1 order by minVal asc;<\/p><\/blockquote>\n","protected":false},"excerpt":{"rendered":"<p>\u9700\u6c42\uff1a\u7b2c\u4e00\u5f20\u56fe\u662f\u539f\u59cb\u6570\u636e\uff0c\u7b2c\u4e8c\u5f20\u56fe\u4e2d\u7684\u987a\u5e8f\u662f\u6309\u6211\u7684\u9700\u6c42\u7684\u6392\u5217\u7ed3\u679c\u3002\u597d\u6bd4\u865a\u62df\u51fa\u6765\u65b0\u7684\u4e00\u5217 e\uff0ce\u7684\u503c\u662fabcd\u4e2d...<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[15330],"tags":[],"class_list":["post-595","post","type-post","status-publish","format-standard","hentry","category-mysql"],"_links":{"self":[{"href":"https:\/\/lnmp.ivan.xin\/index.php?rest_route=\/wp\/v2\/posts\/595","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lnmp.ivan.xin\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lnmp.ivan.xin\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lnmp.ivan.xin\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/lnmp.ivan.xin\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=595"}],"version-history":[{"count":3,"href":"https:\/\/lnmp.ivan.xin\/index.php?rest_route=\/wp\/v2\/posts\/595\/revisions"}],"predecessor-version":[{"id":600,"href":"https:\/\/lnmp.ivan.xin\/index.php?rest_route=\/wp\/v2\/posts\/595\/revisions\/600"}],"wp:attachment":[{"href":"https:\/\/lnmp.ivan.xin\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=595"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lnmp.ivan.xin\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=595"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lnmp.ivan.xin\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=595"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}