{"id":78054,"date":"2024-10-16T11:25:16","date_gmt":"2024-10-16T03:25:16","guid":{"rendered":"https:\/\/server.hk\/cnblog\/78054\/"},"modified":"2024-10-16T11:25:17","modified_gmt":"2024-10-16T03:25:17","slug":"mysql%e6%8c%87%e4%bb%a4-condition%ef%bc%88%e6%a2%9d%e4%bb%b6%ef%bc%89","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/78054\/","title":{"rendered":"MySQL\u6307\u4ee4: CONDITION\uff08\u689d\u4ef6\uff09"},"content":{"rendered":"<h1 id=\"mysql%e6%8c%87%e4%bb%a4-condition%ef%bc%88%e6%a2%9d%e4%bb%b6%ef%bc%89-zPZTNvMvDG\">MySQL\u6307\u4ee4: CONDITION\uff08\u689d\u4ef6\uff09<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0cMySQL\u662f\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u95dc\u806f\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u3002\u5b83\u63d0\u4f9b\u4e86\u591a\u7a2e\u6307\u4ee4\u4f86\u64cd\u4f5c\u548c\u67e5\u8a62\u6578\u64da\uff0c\u5176\u4e2d\u300c\u689d\u4ef6\u300d\u6307\u4ee4\u662f\u975e\u5e38\u91cd\u8981\u7684\u4e00\u90e8\u5206\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0eMySQL\u4e2d\u7684\u689d\u4ef6\u6307\u4ee4\uff0c\u5e6b\u52a9\u8b80\u8005\u66f4\u597d\u5730\u7406\u89e3\u5176\u7528\u6cd5\u53ca\u61c9\u7528\u5834\u666f\u3002<\/p>\n<h2 id=\"%e4%bb%80%e9%ba%bc%e6%98%af%e6%a2%9d%e4%bb%b6%e6%8c%87%e4%bb%a4%ef%bc%9f-zPZTNvMvDG\">\u4ec0\u9ebc\u662f\u689d\u4ef6\u6307\u4ee4\uff1f<\/h2>\n<p>\u689d\u4ef6\u6307\u4ee4\u4e3b\u8981\u7528\u65bc\u5728\u67e5\u8a62\u4e2d\u8a2d\u7f6e\u904e\u6ffe\u689d\u4ef6\uff0c\u4ee5\u4fbf\u5f9e\u6578\u64da\u5eab\u4e2d\u6aa2\u7d22\u7279\u5b9a\u7684\u6578\u64da\u3002\u9019\u4e9b\u689d\u4ef6\u901a\u5e38\u4f7f\u7528\u5728 <code>WHERE<\/code> \u5b50\u53e5\u4e2d\uff0c\u4e26\u4e14\u53ef\u4ee5\u7d50\u5408\u591a\u500b\u689d\u4ef6\u4f86\u9032\u884c\u8907\u96dc\u7684\u67e5\u8a62\u3002<\/p>\n<h2 id=\"%e5%9f%ba%e6%9c%ac%e8%aa%9e%e6%b3%95-zPZTNvMvDG\">\u57fa\u672c\u8a9e\u6cd5<\/h2>\n<p>MySQL\u7684\u57fa\u672c\u689d\u4ef6\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> \u53ef\u4ee5\u662f\u4efb\u4f55\u6709\u6548\u7684\u689d\u4ef6\u8868\u9054\u5f0f\uff0c\u4f8b\u5982\u6bd4\u8f03\u904b\u7b97\u7b26\uff08\u5982 =, &gt;, =, &lt;=, \uff09\u6216\u908f\u8f2f\u904b\u7b97\u7b26\uff08\u5982 AND, OR, NOT\uff09\u3002<\/p>\n<h2 id=\"%e5%b8%b8%e8%a6%8b%e7%9a%84%e6%a2%9d%e4%bb%b6%e9%81%8b%e7%ae%97%e7%ac%a6-zPZTNvMvDG\">\u5e38\u898b\u7684\u689d\u4ef6\u904b\u7b97\u7b26<\/h2>\n<ul>\n<li><strong>=<\/strong>: \u7b49\u65bc<\/li>\n<li><strong>!=<\/strong>: \u4e0d\u7b49\u65bc<\/li>\n<li><strong>&gt;<\/strong>: \u5927\u65bc<\/li>\n<li><strong>&lt;<\/strong>: \u5c0f\u65bc<\/li>\n<li><strong>&gt;=<\/strong>: \u5927\u65bc\u6216\u7b49\u65bc<\/li>\n<li><strong>&lt;=<\/strong>: \u5c0f\u65bc\u6216\u7b49\u65bc<\/li>\n<li><strong>BETWEEN<\/strong>: \u5728\u7bc4\u570d\u5167<\/li>\n<li><strong>LIKE<\/strong>: \u6a21\u7cca\u5339\u914d<\/li>\n<li><strong>IN<\/strong>: \u5728\u6307\u5b9a\u7684\u96c6\u5408\u4e2d<\/li>\n<\/ul>\n<h2 id=\"%e4%bd%bf%e7%94%a8%e7%af%84%e4%be%8b-zPZTNvMvDG\">\u4f7f\u7528\u7bc4\u4f8b<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u4e9b\u4f7f\u7528\u689d\u4ef6\u6307\u4ee4\u7684\u7bc4\u4f8b\uff1a<\/p>\n<h3 id=\"1-%e5%9f%ba%e6%9c%ac%e6%9f%a5%e8%a9%a2-zPZTNvMvDG\">1. \u57fa\u672c\u67e5\u8a62<\/h3>\n<pre><code>SELECT * FROM employees\nWHERE age &gt; 30;<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u5e74\u9f61\u5927\u65bc30\u7684\u54e1\u5de5\u8a18\u9304\u3002<\/p>\n<h3 id=\"2-%e4%bd%bf%e7%94%a8and%e5%92%8cor-zPZTNvMvDG\">2. \u4f7f\u7528AND\u548cOR<\/h3>\n<pre><code>SELECT * FROM employees\nWHERE age &gt; 30 AND department = 'Sales';<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u5e74\u9f61\u5927\u65bc30\u4e14\u90e8\u9580\u70ba\u300c\u92b7\u552e\u300d\u7684\u54e1\u5de5\u8a18\u9304\u3002<\/p>\n<pre><code>SELECT * FROM employees\nWHERE age &lt; 25 OR department = 'HR';<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u5e74\u9f61\u5c0f\u65bc25\u6216\u90e8\u9580\u70ba\u300c\u4eba\u529b\u8cc7\u6e90\u300d\u7684\u54e1\u5de5\u8a18\u9304\u3002<\/p>\n<h3 id=\"3-%e4%bd%bf%e7%94%a8like%e9%80%b2%e8%a1%8c%e6%a8%a1%e7%b3%8a%e6%9f%a5%e8%a9%a2-zPZTNvMvDG\">3. \u4f7f\u7528LIKE\u9032\u884c\u6a21\u7cca\u67e5\u8a62<\/h3>\n<pre><code>SELECT * FROM employees\nWHERE name LIKE 'J%';<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u540d\u5b57\u4ee5\u300cJ\u300d\u958b\u982d\u7684\u54e1\u5de5\u8a18\u9304\u3002<\/p>\n<h3 id=\"4-%e4%bd%bf%e7%94%a8between%e6%9f%a5%e8%a9%a2%e7%af%84%e5%9c%8d-zPZTNvMvDG\">4. \u4f7f\u7528BETWEEN\u67e5\u8a62\u7bc4\u570d<\/h3>\n<pre><code>SELECT * FROM employees\nWHERE salary BETWEEN 30000 AND 50000;<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u85aa\u6c34\u572830000\u523050000\u4e4b\u9593\u7684\u54e1\u5de5\u8a18\u9304\u3002<\/p>\n<h2 id=\"%e7%b5%90%e8%ab%96-zPZTNvMvDG\">\u7d50\u8ad6<\/h2>\n<p>MySQL\u4e2d\u7684\u689d\u4ef6\u6307\u4ee4\u662f\u6578\u64da\u67e5\u8a62\u4e2d\u4e0d\u53ef\u6216\u7f3a\u7684\u4e00\u90e8\u5206\u3002\u901a\u904e\u9748\u6d3b\u904b\u7528\u5404\u7a2e\u689d\u4ef6\u904b\u7b97\u7b26\uff0c\u4f7f\u7528\u8005\u53ef\u4ee5\u7cbe\u78ba\u5730\u6aa2\u7d22\u6240\u9700\u7684\u6578\u64da\uff0c\u5f9e\u800c\u63d0\u9ad8\u6578\u64da\u8655\u7406\u7684\u6548\u7387\u3002\u7121\u8ad6\u662f\u5728\u65e5\u5e38\u7684\u6578\u64da\u7ba1\u7406\u9084\u662f\u8907\u96dc\u7684\u6578\u64da\u5206\u6790\u4e2d\uff0c\u638c\u63e1\u9019\u4e9b\u689d\u4ef6\u6307\u4ee4\u90fd\u5c07\u5927\u5927\u63d0\u5347\u5de5\u4f5c\u6548\u7387\u3002<\/p>\n<p>\u5982\u679c\u60a8\u5c0d\u65bc\u6578\u64da\u5eab\u7ba1\u7406\u6709\u9032\u4e00\u6b65\u7684\u9700\u6c42\uff0c\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u4f86\u642d\u5efa\u60a8\u7684\u6578\u64da\u5eab\u74b0\u5883\uff0c\u4eab\u53d7\u66f4\u9ad8\u6548\u7684\u6578\u64da\u8655\u7406\u80fd\u529b\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3MySQL\u6307\u4ee4\u4e2d\u7684CONDITION\uff08\u689d\u4ef6\uff09\u7528\u6cd5\uff0c\u638c\u63e1\u5982\u4f55\u5728\u67e5\u8a62\u4e2d\u8a2d\u7f6e\u689d\u4ef6\u4ee5\u7be9\u9078\u6578\u64da\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-78054","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78054","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=78054"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78054\/revisions"}],"predecessor-version":[{"id":78055,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78054\/revisions\/78055"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=78054"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=78054"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=78054"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}