{"id":160003,"date":"2024-11-03T19:28:17","date_gmt":"2024-11-03T11:28:17","guid":{"rendered":"https:\/\/server.hk\/cnblog\/160003\/"},"modified":"2024-11-03T19:28:18","modified_gmt":"2024-11-03T11:28:18","slug":"mssql-%e6%95%99%e7%a8%8b-sql-where-%e5%ad%90%e5%8f%a5-2","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/160003\/","title":{"rendered":"MSSQL \u6559\u7a0b SQL WHERE \u5b50\u53e5"},"content":{"rendered":"<h1 id=\"mssql-%e6%95%99%e7%a8%8b-sql-where-%e5%ad%90%e5%8f%a5-AlhqKOFdXO\">MSSQL \u6559\u7a0b SQL WHERE \u5b50\u53e5<\/h1>\n<p>\u5728\u8cc7\u6599\u5eab\u67e5\u8a62\u4e2d\uff0cSQL \u7684 WHERE \u5b50\u53e5\u662f\u4e00\u500b\u975e\u5e38\u91cd\u8981\u7684\u7d44\u4ef6\u3002\u5b83\u7528\u65bc\u904e\u6ffe\u67e5\u8a62\u7d50\u679c\uff0c\u78ba\u4fdd\u53ea\u8fd4\u56de\u7b26\u5408\u7279\u5b9a\u689d\u4ef6\u7684\u6578\u64da\u3002\u5728 Microsoft SQL Server\uff08MSSQL\uff09\u4e2d\uff0cWHERE \u5b50\u53e5\u7684\u4f7f\u7528\u65b9\u5f0f\u8207\u5176\u4ed6 SQL \u6578\u64da\u5eab\u7cfb\u7d71\u76f8\u4f3c\uff0c\u4f46\u4e5f\u6709\u5176\u7368\u7279\u4e4b\u8655\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e MSSQL \u4e2d\u7684 WHERE \u5b50\u53e5\uff0c\u5305\u62ec\u5176\u8a9e\u6cd5\u3001\u4f7f\u7528\u7bc4\u4f8b\u53ca\u6700\u4f73\u5be6\u8e10\u3002<\/p>\n<h2 id=\"where-%e5%ad%90%e5%8f%a5%e7%9a%84%e5%9f%ba%e6%9c%ac%e8%aa%9e%e6%b3%95-AlhqKOFdXO\">WHERE \u5b50\u53e5\u7684\u57fa\u672c\u8a9e\u6cd5<\/h2>\n<p>WHERE \u5b50\u53e5\u901a\u5e38\u8207 SELECT\u3001UPDATE \u6216 DELETE \u8a9e\u53e5\u4e00\u8d77\u4f7f\u7528\u3002\u5176\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT column1, column2, ...\nFROM table_name\nWHERE condition;<\/code><\/pre>\n<p>\u5728\u9019\u88e1\uff0c<code>condition<\/code> \u662f\u4e00\u500b\u8868\u9054\u5f0f\uff0c\u7528\u65bc\u6307\u5b9a\u8981\u904e\u6ffe\u7684\u689d\u4ef6\u3002\u53ea\u6709\u6eff\u8db3\u8a72\u689d\u4ef6\u7684\u8a18\u9304\u624d\u6703\u88ab\u8fd4\u56de\u6216\u5f71\u97ff\u3002<\/p>\n<h2 id=\"%e4%bd%bf%e7%94%a8-where-%e5%ad%90%e5%8f%a5%e7%9a%84%e7%af%84%e4%be%8b-AlhqKOFdXO\">\u4f7f\u7528 WHERE \u5b50\u53e5\u7684\u7bc4\u4f8b<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u4e9b\u4f7f\u7528 WHERE \u5b50\u53e5\u7684\u7bc4\u4f8b\uff1a<\/p>\n<h3 id=\"1-%e9%81%b8%e6%93%87%e7%89%b9%e5%ae%9a%e6%a2%9d%e4%bb%b6%e7%9a%84%e6%95%b8%e6%93%9a-AlhqKOFdXO\">1. \u9078\u64c7\u7279\u5b9a\u689d\u4ef6\u7684\u6578\u64da<\/h3>\n<p>\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba <code>Employees<\/code> \u7684\u8868\u683c\uff0c\u5305\u542b\u54e1\u5de5\u7684\u59d3\u540d\u548c\u5e74\u9f61\u3002\u6211\u5011\u60f3\u8981\u67e5\u8a62\u5e74\u9f61\u5927\u65bc 30 \u6b72\u7684\u54e1\u5de5\uff1a<\/p>\n<pre><code>SELECT Name, Age\nFROM Employees\nWHERE Age &gt; 30;<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u5e74\u9f61\u5927\u65bc 30 \u7684\u54e1\u5de5\u59d3\u540d\u548c\u5e74\u9f61\u3002<\/p>\n<h3 id=\"2-%e4%bd%bf%e7%94%a8%e5%a4%9a%e5%80%8b%e6%a2%9d%e4%bb%b6-AlhqKOFdXO\">2. \u4f7f\u7528\u591a\u500b\u689d\u4ef6<\/h3>\n<p>\u6211\u5011\u4e5f\u53ef\u4ee5\u4f7f\u7528 AND \u548c OR \u4f86\u7d44\u5408\u591a\u500b\u689d\u4ef6\u3002\u4f8b\u5982\uff0c\u67e5\u8a62\u5e74\u9f61\u5927\u65bc 30 \u4e14\u90e8\u9580\u70ba &#8216;Sales&#8217; \u7684\u54e1\u5de5\uff1a<\/p>\n<pre><code>SELECT Name, Age, Department\nFROM Employees\nWHERE Age &gt; 30 AND Department = 'Sales';<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u5e74\u9f61\u5927\u65bc 30 \u4e14\u5728\u92b7\u552e\u90e8\u9580\u5de5\u4f5c\u7684\u54e1\u5de5\u3002<\/p>\n<h3 id=\"3-%e4%bd%bf%e7%94%a8-like-%e9%80%b2%e8%a1%8c%e6%a8%a1%e7%b3%8a%e6%9f%a5%e8%a9%a2-AlhqKOFdXO\">3. \u4f7f\u7528 LIKE \u9032\u884c\u6a21\u7cca\u67e5\u8a62<\/h3>\n<p>\u5982\u679c\u6211\u5011\u60f3\u8981\u67e5\u8a62\u59d3\u540d\u4e2d\u5305\u542b &#8216;John&#8217; \u7684\u6240\u6709\u54e1\u5de5\uff0c\u53ef\u4ee5\u4f7f\u7528 LIKE \u95dc\u9375\u5b57\uff1a<\/p>\n<pre><code>SELECT Name, Age\nFROM Employees\nWHERE Name LIKE '%John%';<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u59d3\u540d\u4e2d\u5305\u542b &#8216;John&#8217; \u7684\u54e1\u5de5\u3002<\/p>\n<h2 id=\"where-%e5%ad%90%e5%8f%a5%e4%b8%ad%e7%9a%84-null-%e5%80%bc-AlhqKOFdXO\">WHERE \u5b50\u53e5\u4e2d\u7684 NULL \u503c<\/h2>\n<p>\u5728 MSSQL \u4e2d\uff0cNULL \u503c\u7684\u8655\u7406\u4e5f\u9700\u8981\u7279\u5225\u6ce8\u610f\u3002\u8981\u67e5\u8a62\u67d0\u500b\u6b04\u4f4d\u70ba NULL \u7684\u8a18\u9304\uff0c\u53ef\u4ee5\u4f7f\u7528 IS NULL\uff1a<\/p>\n<pre><code>SELECT Name, Age\nFROM Employees\nWHERE Department IS NULL;<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u90e8\u9580\u70ba NULL \u7684\u54e1\u5de5\u3002<\/p>\n<h2 id=\"%e6%9c%80%e4%bd%b3%e5%af%a6%e8%b8%90-AlhqKOFdXO\">\u6700\u4f73\u5be6\u8e10<\/h2>\n<ul>\n<li><strong>\u4f7f\u7528\u7d22\u5f15\uff1a<\/strong>\u5728 WHERE \u5b50\u53e5\u4e2d\u4f7f\u7528\u7684\u6b04\u4f4d\u61c9\u8003\u616e\u5efa\u7acb\u7d22\u5f15\uff0c\u4ee5\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u3002<\/li>\n<li><strong>\u907f\u514d\u4f7f\u7528 SELECT *\uff1a<\/strong>\u660e\u78ba\u6307\u5b9a\u6240\u9700\u7684\u6b04\u4f4d\uff0c\u9019\u6a23\u53ef\u4ee5\u6e1b\u5c11\u4e0d\u5fc5\u8981\u7684\u6578\u64da\u50b3\u8f38\u3002<\/li>\n<li><strong>\u4f7f\u7528\u62ec\u865f\uff1a<\/strong>\u5728\u8907\u96dc\u7684\u689d\u4ef6\u4e2d\u4f7f\u7528\u62ec\u865f\u4f86\u660e\u78ba\u904b\u7b97\u9806\u5e8f\uff0c\u907f\u514d\u908f\u8f2f\u932f\u8aa4\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b8%bd%e7%b5%90-AlhqKOFdXO\">\u7e3d\u7d50<\/h2>\n<p>WHERE \u5b50\u53e5\u662f MSSQL \u4e2d\u9032\u884c\u6578\u64da\u67e5\u8a62\u7684\u91cd\u8981\u5de5\u5177\uff0c\u80fd\u5920\u5e6b\u52a9\u7528\u6236\u7cbe\u78ba\u5730\u904e\u6ffe\u6240\u9700\u7684\u6578\u64da\u3002\u901a\u904e\u5408\u7406\u4f7f\u7528 WHERE \u5b50\u53e5\uff0c\u914d\u5408\u9069\u7576\u7684\u689d\u4ef6\u548c\u6700\u4f73\u5be6\u8e10\uff0c\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u6548\u7387\u548c\u6e96\u78ba\u6027\u3002\u82e5\u60a8\u9700\u8981\u9032\u4e00\u6b65\u4e86\u89e3\u5982\u4f55\u5728 <a href=\"https:\/\/server.hk\">\u9999\u6e2f\u4f3a\u670d\u5668<\/a> \u4e0a\u4f7f\u7528 MSSQL\uff0c\u6216\u5c0b\u627e\u5408\u9069\u7684 <a href=\"https:\/\/server.hk\">VPS<\/a> \u89e3\u6c7a\u65b9\u6848\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4ee5\u7372\u53d6\u66f4\u591a\u8cc7\u8a0a\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b66\u4e60MSSQL\u6559\u7a0b\u4e2d\u7684SQL WHERE\u5b50\u53e5\uff0c\u638c\u63e1\u5982\u4f55\u6709\u6548\u7b5b\u9009\u6570\u636e\uff0c\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\u548c\u51c6\u786e\u6027\u3002<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-160003","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/160003","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=160003"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/160003\/revisions"}],"predecessor-version":[{"id":160004,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/160003\/revisions\/160004"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=160003"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=160003"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=160003"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}