{"id":1601,"date":"2011-03-12T03:02:51","date_gmt":"2011-03-12T03:02:51","guid":{"rendered":"http:\/\/enjoyasp.net\/?p=1601"},"modified":"2011-06-17T00:48:34","modified_gmt":"2011-06-17T00:48:34","slug":"sql%e8%af%ad%e5%8f%a5%e6%89%a7%e8%a1%8c%e9%a1%ba%e5%ba%8f","status":"publish","type":"post","link":"https:\/\/enjoyasp.net\/index.php\/2011\/03\/12\/sql%e8%af%ad%e5%8f%a5%e6%89%a7%e8%a1%8c%e9%a1%ba%e5%ba%8f\/","title":{"rendered":"SQL\u8bed\u53e5\u6267\u884c\u987a\u5e8f"},"content":{"rendered":"<pre escaped=\"true\" lang=\"tsql\">\r\n 1\uff0cFROM\u9636\u6bb5\r\n   1)\u4eceFROM\u6267\u884c\uff0c\u5bf9\u4e8eJOIN\uff0c\u4e24\u8868\u8fdb\u884c\u4ea4\u53c9\u8fde\u63a5\uff0c\u6c42\u7b1b\u5361\u5c14\u79ef\u5f97\u5230\u4e00\u4e2a\u7ed3\u679c\u96c6\u3002\r\n   2)\u6839\u636eON\u6761\u4ef6\uff0c\u5bf9\u7ed3\u679c\u96c6\u4e0d\u6ee1\u8db3\u6761\u4ef6\u7684\u8bb0\u5f55\u53bb\u9664\r\n   3)\u82e5\u6709\u5916\u8fde\u63a5\uff0c\u5982LEFT,RIGHT\u7b49\uff0c\u518d\u5c06\u6ee1\u8db3\u6761\u4ef6\u7684\u52a0\u5165\u5230\u7ed3\u679c\u96c6\u4e2d\r\n   4)\u6267\u884cAPPLY,PIVOT,UNPIVOT\u7b49\u8868\u8fbe\u5f0f\r\n2\uff0cWHERE\u9636\u6bb5\uff1a\u5bf9\u4e8e1\u6b65\u9aa4\u5f97\u5230\u7684\u865a\u8868\uff0c\u5c06where\u6761\u4ef6\u4e3atrue\u7684\u4fdd\u7559\u4e0b\u6765\r\n3\uff0cGROUP BY \u9636\u6bb5 \u5bf9\u865a\u62df\u8868\u8fdb\u884c\u5206\u7ec4\r\n4\uff0cHAVING\u9636\u6bb5\uff0c\u5bf9\u5206\u7ec4\u540e\u7684\u865a\u62df\u8868\u8fdb\u884c\u7b5b\u9009\r\n5\uff0cSELECT\/UPDATE\/DELETE\u9636\u6bb5\uff0c\u6295\u5f71\u53d6\u5f97\u5217\u6570\u636e,\u82e5\u6709TOP,\u5219\u4f1a\u6839\u636eORDER BY \u5b50\u53e5\u6765\u9009\u62e9\u6307\u5b9a\u6570\u91cf\u7684\u884c\r\n6\uff0cORDER BY \u9636\u6bb5 \u5bf9\u4e0a\u8ff0\u7ed3\u679c\u8fdb\u884c\u6392\u5e8f\uff0c\u8fd4\u56de\u6e38\u6807\r\n\r\n\u7531\u4e0a\u77e5\uff1a1\uff0cGROUP BY \u662fHAVING\u7684\u57fa\u7840\uff0c\u9700\u8981\u5148\u6267\u884cGROUP BY \u518d\u6267\u884cHAVING\r\n        2, WHERE\u6bd4SELECT\u5148\u6267\u884c\uff0c\u6545\u5728SELECT\u4e2d\u6307\u5b9a\u7684\u865a\u5217\u5728WHERE\u6761\u4ef6\u4e2d\u4e0d\u53ef\u7528\uff0c\u800cSELECT\u6bd4ORDER BY \u5148\u6267\u884c\uff0c\u6545\u5728SELECT\u4e2d\u6307\u5b9a\u7684\u865a\u5217\u5728ORDER BY\u6761\u4ef6\u4e2d\u53ef\u4ee5\u4f7f\u7528\r\n     SELECT f.UserName,SUM(amount) amo --amo:\u865a\u5217\uff0c\u6307\u5728\u539f\u6709\u8868\u4e2d\u4e0d\u5b58\u5728\u7684\u5217\r\n     FROM bdOrder\r\n     ORDER BY amo\r\n       3\uff0c\u82e5\u4f7f\u7528ORDER BY\uff0c\u5219\u8fd4\u56de\u7684\u662f\u4e00\u4e2a\u6e38\u6807\uff0c\u4e0d\u80fd\u7528\u5728FROM\u540e\u9762\uff0c\u56e0\u4e3aFROM\u540e\u9762\u8ddf\u7684\u662f\u7ed3\u679c\u96c6\r\n        SELECT * FROM ( SELECT * FROM frmuser ORDER BY Account )f \u8fd9\u6837\u662f\u9519\u8bef\u7684\r\n       \u4f8b\u5916\uff1a\u53ef\u901a\u8fc7\u52a0TOP\u89e3\u51b3\r\n    SELECT * FROM ( SELECT TOP * FROM frmuser ORDER BY Account )f\r\n4\uff1a\u5f53Select\u672a\u4f7f\u7528Distinct\u65f6\uff0cOrder By\u53ef\u4f7f\u7528Select\u4e4b\u524d\u7684\u5b57\u6bb5\uff0c\u5373\uff1a\u5373\u4f7f\u5728Select\u4e2d\u4e0d\u5b58\u5728\uff0c\u4f46\u5728\u8868\u4e2d\u5b58\u5728\u7684\u5b57\u6bb5\uff0cOrder By\u4e5f\u53ef\u5f15\u7528\u5f53Select\u4f7f\u7528Distinct\u65f6\uff0cOrder By\u53ea\u80fd\u4f7f\u7528Select\u4e2d\u7684\u5b57\u6bb5\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>1\uff0cFROM\u9636\u6bb5 1)\u4eceFROM\u6267\u884c\uff0c\u5bf9\u4e8eJOIN\uff0c\u4e24\u8868\u8fdb\u884c\u4ea4\u53c9\u8fde\u63a5\uff0c\u6c42\u7b1b\u5361\u5c14\u79ef\u5f97\u5230\u4e00\u4e2a\u7ed3\u679c\u96c6\u3002 2)\u6839\u636eON [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[36],"tags":[],"class_list":["post-1601","post","type-post","status-publish","format-standard","hentry","category-sql-server"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/posts\/1601","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/comments?post=1601"}],"version-history":[{"count":0,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/posts\/1601\/revisions"}],"wp:attachment":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/media?parent=1601"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/categories?post=1601"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/tags?post=1601"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}