{"id":78772,"date":"2024-10-16T12:18:15","date_gmt":"2024-10-16T04:18:15","guid":{"rendered":"https:\/\/server.hk\/cnblog\/78772\/"},"modified":"2024-10-16T12:18:15","modified_gmt":"2024-10-16T04:18:15","slug":"mysql%e6%8c%87%e4%bb%a4-is-not-null%ef%bc%88%e4%b8%8d%e7%82%ba%e7%a9%ba%ef%bc%89","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/78772\/","title":{"rendered":"MySQL\u6307\u4ee4: IS NOT NULL\uff08\u4e0d\u70ba\u7a7a\uff09"},"content":{"rendered":"<h1 id=\"mysql%e6%8c%87%e4%bb%a4-is-not-null%ef%bc%88%e4%b8%8d%e7%82%ba%e7%a9%ba%ef%bc%89-GMLtECFKHE\">MySQL\u6307\u4ee4: IS NOT NULL\uff08\u4e0d\u70ba\u7a7a\uff09<\/h1>\n<p>\u5728\u8cc7\u6599\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cMySQL\u662f\u4e00\u500b\u5ee3\u6cdb\u4f7f\u7528\u7684\u95dc\u806f\u5f0f\u8cc7\u6599\u5eab\u7ba1\u7406\u7cfb\u7d71\u3002\u7576\u6211\u5011\u5728\u9032\u884c\u8cc7\u6599\u67e5\u8a62\u6642\uff0c\u5e38\u5e38\u9700\u8981\u6aa2\u67e5\u67d0\u4e9b\u6b04\u4f4d\u7684\u503c\u662f\u5426\u70ba\u7a7a\u3002\u9019\u6642\uff0cIS NOT NULL\u6307\u4ee4\u4fbf\u6210\u70ba\u4e00\u500b\u975e\u5e38\u91cd\u8981\u7684\u5de5\u5177\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0eIS NOT NULL\u7684\u7528\u6cd5\u53ca\u5176\u5728\u5be6\u969b\u61c9\u7528\u4e2d\u7684\u91cd\u8981\u6027\u3002<\/p>\n<h2 id=\"is-not-null%e7%9a%84%e5%9f%ba%e6%9c%ac%e6%a6%82%e5%bf%b5-GMLtECFKHE\">IS NOT NULL\u7684\u57fa\u672c\u6982\u5ff5<\/h2>\n<p>\u5728MySQL\u4e2d\uff0cNULL\u662f\u4e00\u500b\u7279\u6b8a\u7684\u6a19\u8a18\uff0c\u7528\u4f86\u8868\u793a\u7f3a\u5931\u6216\u672a\u77e5\u7684\u6578\u64da\u3002\u7576\u4e00\u500b\u6b04\u4f4d\u7684\u503c\u70baNULL\u6642\uff0c\u9019\u610f\u5473\u8457\u8a72\u6b04\u4f4d\u6c92\u6709\u4efb\u4f55\u6578\u64da\u3002\u76f8\u5c0d\u5730\uff0cIS NOT NULL\u6307\u4ee4\u7528\u4f86\u6aa2\u67e5\u67d0\u500b\u6b04\u4f4d\u7684\u503c\u662f\u5426\u4e0d\u70baNULL\uff0c\u4e5f\u5c31\u662f\u8aaa\uff0c\u8a72\u6b04\u4f4d\u5fc5\u9808\u6709\u6709\u6548\u7684\u6578\u64da\u3002<\/p>\n<h2 id=\"is-not-null%e7%9a%84%e8%aa%9e%e6%b3%95-GMLtECFKHE\">IS NOT NULL\u7684\u8a9e\u6cd5<\/h2>\n<p>IS NOT NULL\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT column1, column2, ...\nFROM table_name\nWHERE column_name IS NOT NULL;<\/code><\/pre>\n<p>\u5728\u9019\u6bb5\u8a9e\u6cd5\u4e2d\uff0c<code>column_name<\/code>\u662f\u4f60\u60f3\u8981\u6aa2\u67e5\u7684\u6b04\u4f4d\u540d\u7a31\uff0c\u800c<code>table_name<\/code>\u5247\u662f\u8cc7\u6599\u8868\u7684\u540d\u7a31\u3002\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u5728\u6307\u5b9a\u6b04\u4f4d\u4e2d\u4e0d\u70baNULL\u7684\u8a18\u9304\u3002<\/p>\n<h2 id=\"%e5%af%a6%e9%9a%9b%e6%87%89%e7%94%a8%e7%af%84%e4%be%8b-GMLtECFKHE\">\u5be6\u969b\u61c9\u7528\u7bc4\u4f8b<\/h2>\n<p>\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba<code>employees<\/code>\u7684\u8cc7\u6599\u8868\uff0c\u8a72\u8868\u5305\u542b\u4ee5\u4e0b\u6b04\u4f4d\uff1a<\/p>\n<ul>\n<li><code>id<\/code> &#8211; \u54e1\u5de5\u7de8\u865f<\/li>\n<li><code>name<\/code> &#8211; \u54e1\u5de5\u59d3\u540d<\/li>\n<li><code>email<\/code> &#8211; \u54e1\u5de5\u96fb\u5b50\u90f5\u4ef6<\/li>\n<li><code>phone<\/code> &#8211; \u54e1\u5de5\u96fb\u8a71<\/li>\n<\/ul>\n<p>\u5982\u679c\u6211\u5011\u60f3\u8981\u67e5\u8a62\u6240\u6709\u64c1\u6709\u96fb\u5b50\u90f5\u4ef6\u5730\u5740\u7684\u54e1\u5de5\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u67e5\u8a62\uff1a<\/p>\n<pre><code>SELECT id, name, email\nFROM employees\nWHERE email IS NOT NULL;<\/code><\/pre>\n<p>\u9019\u689d\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u96fb\u5b50\u90f5\u4ef6\u6b04\u4f4d\u4e0d\u70baNULL\u7684\u54e1\u5de5\u8a18\u9304\uff0c\u5e6b\u52a9\u6211\u5011\u5feb\u901f\u627e\u5230\u64c1\u6709\u6709\u6548\u96fb\u5b50\u90f5\u4ef6\u7684\u54e1\u5de5\u3002<\/p>\n<h2 id=\"is-not-null%e7%9a%84%e4%bd%bf%e7%94%a8%e5%a0%b4%e6%99%af-GMLtECFKHE\">IS NOT NULL\u7684\u4f7f\u7528\u5834\u666f<\/h2>\n<p>IS NOT NULL\u6307\u4ee4\u5728\u591a\u7a2e\u60c5\u6cc1\u4e0b\u90fd\u975e\u5e38\u6709\u7528\uff0c\u4ee5\u4e0b\u662f\u4e00\u4e9b\u5e38\u898b\u7684\u4f7f\u7528\u5834\u666f\uff1a<\/p>\n<ul>\n<li><strong>\u6578\u64da\u6e05\u7406\uff1a<\/strong>\u5728\u9032\u884c\u6578\u64da\u5206\u6790\u4e4b\u524d\uff0c\u78ba\u4fdd\u6578\u64da\u7684\u5b8c\u6574\u6027\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002\u4f7f\u7528IS NOT NULL\u53ef\u4ee5\u5e6b\u52a9\u8b58\u5225\u7f3a\u5931\u7684\u6578\u64da\u3002<\/li>\n<li><strong>\u5831\u544a\u751f\u6210\uff1a<\/strong>\u5728\u751f\u6210\u5831\u544a\u6642\uff0c\u901a\u5e38\u9700\u8981\u6392\u9664\u90a3\u4e9b\u7f3a\u5c11\u95dc\u9375\u6578\u64da\u7684\u8a18\u9304\uff0c\u4ee5\u78ba\u4fdd\u5831\u544a\u7684\u6e96\u78ba\u6027\u3002<\/li>\n<li><strong>\u6578\u64da\u9a57\u8b49\uff1a<\/strong>\u5728\u63d2\u5165\u6216\u66f4\u65b0\u6578\u64da\u6642\uff0c\u53ef\u4ee5\u4f7f\u7528IS NOT NULL\u4f86\u9a57\u8b49\u67d0\u4e9b\u6b04\u4f4d\u662f\u5426\u5fc5\u9808\u586b\u5beb\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b5%90%e8%ab%96-GMLtECFKHE\">\u7d50\u8ad6<\/h2>\n<p>IS NOT NULL\u662f\u4e00\u500b\u5f37\u5927\u7684MySQL\u6307\u4ee4\uff0c\u80fd\u5920\u5e6b\u52a9\u7528\u6236\u6709\u6548\u5730\u7be9\u9078\u51fa\u4e0d\u70ba\u7a7a\u7684\u6578\u64da\u3002\u7121\u8ad6\u662f\u5728\u6578\u64da\u6e05\u7406\u3001\u5831\u544a\u751f\u6210\u9084\u662f\u6578\u64da\u9a57\u8b49\u4e2d\uff0c\u9019\u500b\u6307\u4ee4\u90fd\u626e\u6f14\u8457\u91cd\u8981\u7684\u89d2\u8272\u3002\u638c\u63e1IS NOT NULL\u7684\u7528\u6cd5\uff0c\u5c07\u6709\u52a9\u65bc\u63d0\u5347\u8cc7\u6599\u5eab\u64cd\u4f5c\u7684\u6548\u7387\u548c\u6e96\u78ba\u6027\u3002<\/p>\n<p>\u5982\u679c\u60a8\u5c0d\u65bc\u8cc7\u6599\u5eab\u7ba1\u7406\u6216\u5176\u4ed6\u76f8\u95dc\u6280\u8853\u6709\u8208\u8da3\uff0c\u6b61\u8fce\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u4e86\u89e3\u66f4\u591a\u8cc7\u8a0a\uff0c\u7279\u5225\u662f\u6211\u5011\u63d0\u4f9b\u7684<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u89e3\u6c7a\u65b9\u6848\uff0c\u52a9\u60a8\u5728\u6578\u64da\u7ba1\u7406\u4e0a\u66f4\u4e0a\u4e00\u5c64\u6a13\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3MySQL\u6307\u4ee4IS NOT NULL\uff0c\u78ba\u4fdd\u6578\u64da\u5eab\u4e2d\u5b57\u6bb5\u4e0d\u70ba\u7a7a\uff0c\u63d0\u5347\u67e5\u8a62\u6548\u7387\u8207\u6578\u64da\u5b8c\u6574\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-78772","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78772","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=78772"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78772\/revisions"}],"predecessor-version":[{"id":78773,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78772\/revisions\/78773"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=78772"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=78772"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=78772"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}