{"id":1421,"date":"2010-11-25T08:54:37","date_gmt":"2010-11-25T08:54:37","guid":{"rendered":"http:\/\/enjoyasp.net\/?p=1421"},"modified":"2010-11-25T08:54:37","modified_gmt":"2010-11-25T08:54:37","slug":"sql-server-%e4%b8%b4%e6%97%b6%e7%bb%93%e6%9e%9c%e9%9b%86%e4%b8%8e%e9%80%92%e5%bd%92-cte","status":"publish","type":"post","link":"https:\/\/enjoyasp.net\/index.php\/2010\/11\/25\/sql-server-%e4%b8%b4%e6%97%b6%e7%bb%93%e6%9e%9c%e9%9b%86%e4%b8%8e%e9%80%92%e5%bd%92-cte\/","title":{"rendered":"Sql Server \u4e34\u65f6\u7ed3\u679c\u96c6\u4e0e\u9012\u5f52-CTE"},"content":{"rendered":"<pre lang=\"tsql\">\r\nCTE: Common Table Express \u6307\u5b9a\u4e34\u65f6\u547d\u540d\u7684\u7ed3\u679c\u96c6\r\n\r\n1, \u5f53sql\u8bed\u53e5\u6bd4\u8f83\u5927\u65f6\uff0c\u53ef\u4ee5\u7528CTE\u5c06\u5c0f\u7ed3\u679c\u96c6\u62c6\u5206\uff0c\u4ee5\u4fbf\u9605\u8bfb\r\n    WITH mycre(id,name) AS ( select id ,name from mddepartment )\r\n    SELECT * FROM frmuser JOIN mycre ON frmuser.DepartmentID= mycre.id\r\n \u6ce8\uff1a1\uff09CTE \u4e4b\u540e\u5fc5\u987b\u76f4\u63a5\u4f7f\u7528\uff0c\u95f4\u9694sql\u8bed\u53e5\u5c31\u4f1a\u5931\u6548\r\n        2\uff09\u5728\u7528with\u65f6\u5e76\u4e0d\u4f1a\u6267\u884c\u67e5\u8be2\uff0c\u53ea\u662f\u51d1sql\u8bed\u53e5\uff0c\u53ea\u6709\u5f53with\u540e\u9762\u7684select *\u5f15\u7528cte\u65f6\u624d\u4f1a\u6267\u884c\r\n\r\n2\uff0c\u9012\u5f52\u4f7f\u7528\uff0c\u4f9d\u6b21\u5f15\u7528\u81ea\u8eab\u3002\u9012\u5f52 CTE \u5b9a\u4e49\u81f3\u5c11\u5fc5\u987b\u5305\u542b\u4e24\u4e2a CTE \u67e5\u8be2\u5b9a\u4e49\uff08\u4e00\u4e2a\u5b9a\u4f4d\u70b9\u6210\u5458\u548c\u4e00\u4e2a\u9012\u5f52\u6210\u5458\uff09\r\n WITH departments(id,Departname,depth) as(\r\n    SELECT id,Departname,1 depth FROM mdDepartment md\r\n    WHERE md.ParentID = 2   --\u627e\u5230\u5e7f\u544a\u5546\u52a1\u90e8\u7684\u76f4\u63a5\u5b50\u90e8\u95e8 \u5b9a\u4f4d\u70b9\u6210\u5458\uff0cdepth\u6307\u5b9a\u6df1\u5ea6\r\n    UNION ALL\r\n    SELECT md.id,md.Departname,depth+1 FROM mdDepartment md --\u627e\u5230\u5b50\u90e8\u95e8\u7684\u5b50\u90e8\u95e8 \u9012\u5f52\u6210\u5458\r\n    JOIN departments d ON md.ParentID = d.id\r\n   \r\n)\r\nSELECT * FROM departments\r\n    \u6ce8\uff1a1\uff09\u5b9a\u4f4d\u70b9\u6210\u5458\u4e4b\u95f4\u5fc5\u987b\u4f7f\u7528UNION ALL\u3001UNION\u3001INTERSECT\u3001EXCEPT\u96c6\u5408\u8fd0\u7b97\u7b26\uff0c\u6700\u540e\u4e00\u4e2a\u5b9a\u4f4d\u70b9\u6210\u5458\u4e0e\u9012\u5f52\u6210\u5458\u4e4b\u95f4\u5fc5\u987b\u4f7f\u7528UNION ALL\uff0c\u9012\u5f52\u6210\u5458\u4e4b\u95f4\u4e5f\u5fc5\u987b\u4f7f\u7528UNION ALL\u8fde\u63a5\uff0c\u5b9a\u4f4d\u70b9\u6210\u5458\u548c\u9012\u5f52\u6210\u5458\u4e2d\u7684\u5b57\u6bb5\u6570\u91cf\u548c\u7c7b\u578b\u5fc5\u987b\u5b8c\u5168\u4e00\u81f4\uff0c\u9012\u5f52\u6210\u5458\u7684FROM\u5b50\u53e5\u53ea\u80fd\u5f15\u7528\u4e00\u6b21CTE\u5bf9\u8c61\u3002\r\n           2\uff09\u9012\u5f52\u6210\u5458\u4e2d\u4e0d\u5141\u8bb8\u51fa\u73b0\u4e0b\u5217\u9879\r\n\u3000\u3000            SELECT DISTINCT\r\n\u3000\u3000            GROUP BY\r\n\u3000\u3000            HAVING\r\n\u3000\u3000            \u6807\u91cf\u805a\u5408\r\n\u3000\u3000            TOP\r\n\u3000\u3000            LEFT\u3001RIGHT\u3001OUTER JOIN(\u5141\u8bb8\u51fa\u73b0 INNER JOIN)\r\n\u3000\u3000            \u5b50\u67e5\u8be2\r\n\r\n<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>CTE: Common Table Express \u6307\u5b9a\u4e34\u65f6\u547d\u540d\u7684\u7ed3\u679c\u96c6 1, \u5f53sql\u8bed\u53e5\u6bd4\u8f83\u5927\u65f6\uff0c\u53ef\u4ee5\u7528C [&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-1421","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\/1421","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=1421"}],"version-history":[{"count":0,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/posts\/1421\/revisions"}],"wp:attachment":[{"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/media?parent=1421"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/categories?post=1421"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/enjoyasp.net\/index.php\/wp-json\/wp\/v2\/tags?post=1421"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}