{"id":175387,"date":"2024-11-08T05:27:19","date_gmt":"2024-11-07T21:27:19","guid":{"rendered":"https:\/\/server.hk\/cnblog\/175387\/"},"modified":"2024-11-08T05:27:19","modified_gmt":"2024-11-07T21:27:19","slug":"%e5%a6%82%e4%bd%95%e4%bd%bf%e7%94%a8select%e5%91%bd%e4%bb%a4%e5%9c%a8%e9%8f%88%e6%8e%a5%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e6%9f%a5%e8%a9%a2%e6%95%b8%e6%93%9a%ef%bc%9f-%e9%8f%88%e6%8e%a5%e6%95%b8","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/175387\/","title":{"rendered":"\u5982\u4f55\u4f7f\u7528select\u547d\u4ee4\u5728\u93c8\u63a5\u6578\u64da\u5eab\u4e2d\u67e5\u8a62\u6578\u64da\uff1f (\u93c8\u63a5\u6578\u64da\u5eabselect)"},"content":{"rendered":"<h1 id=\"%e5%a6%82%e4%bd%95%e4%bd%bf%e7%94%a8select%e5%91%bd%e4%bb%a4%e5%9c%a8%e9%8f%88%e6%8e%a5%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e6%9f%a5%e8%a9%a2%e6%95%b8%e6%93%9a%ef%bc%9f-ZKGMAePDxJ\">\u5982\u4f55\u4f7f\u7528SELECT\u547d\u4ee4\u5728\u93c8\u63a5\u6578\u64da\u5eab\u4e2d\u67e5\u8a62\u6578\u64da\uff1f<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0cSQL\uff08\u7d50\u69cb\u5316\u67e5\u8a62\u8a9e\u8a00\uff09\u662f\u4e00\u7a2e\u7528\u65bc\u67e5\u8a62\u548c\u64cd\u4f5c\u6578\u64da\u7684\u6a19\u6e96\u8a9e\u8a00\u3002\u5176\u4e2d\uff0c<code>SELECT<\/code>\u547d\u4ee4\u662f\u6700\u5e38\u7528\u7684\u547d\u4ee4\u4e4b\u4e00\uff0c\u4e3b\u8981\u7528\u65bc\u5f9e\u6578\u64da\u5eab\u4e2d\u6aa2\u7d22\u6578\u64da\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e\u5982\u4f55\u4f7f\u7528<code>SELECT<\/code>\u547d\u4ee4\u5728\u93c8\u63a5\u6578\u64da\u5eab\u4e2d\u67e5\u8a62\u6578\u64da\uff0c\u4e26\u63d0\u4f9b\u4e00\u4e9b\u5be6\u7528\u7684\u793a\u4f8b\u548c\u6280\u5de7\u3002<\/p>\n<h2 id=\"select%e5%91%bd%e4%bb%a4%e7%9a%84%e5%9f%ba%e6%9c%ac%e8%aa%9e%e6%b3%95-ZKGMAePDxJ\">SELECT\u547d\u4ee4\u7684\u57fa\u672c\u8a9e\u6cd5<\/h2>\n<p><code>SELECT<\/code>\u547d\u4ee4\u7684\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>column1, column2, ...<\/code>\u662f\u60a8\u5e0c\u671b\u67e5\u8a62\u7684\u5217\u540d\uff0c<code>table_name<\/code>\u662f\u60a8\u8981\u67e5\u8a62\u7684\u8868\u540d\uff0c\u800c<code>condition<\/code>\u5247\u662f\u53ef\u9078\u7684\u689d\u4ef6\uff0c\u7528\u65bc\u904e\u6ffe\u7d50\u679c\u3002<\/p>\n<h2 id=\"%e6%9f%a5%e8%a9%a2%e6%89%80%e6%9c%89%e5%88%97-ZKGMAePDxJ\">\u67e5\u8a62\u6240\u6709\u5217<\/h2>\n<p>\u5982\u679c\u60a8\u5e0c\u671b\u5f9e\u67d0\u500b\u8868\u4e2d\u67e5\u8a62\u6240\u6709\u5217\uff0c\u53ef\u4ee5\u4f7f\u7528\u661f\u865f\uff08<code>*<\/code>\uff09\u4f86\u4ee3\u66ff\u5217\u540d\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT * FROM employees;<\/code><\/pre>\n<p>\u9019\u689d\u547d\u4ee4\u5c07\u8fd4\u56de<code>employees<\/code>\u8868\u4e2d\u7684\u6240\u6709\u6578\u64da\u3002<\/p>\n<h2 id=\"%e4%bd%bf%e7%94%a8where%e5%ad%90%e5%8f%a5%e9%81%8e%e6%bf%be%e6%95%b8%e6%93%9a-ZKGMAePDxJ\">\u4f7f\u7528WHERE\u5b50\u53e5\u904e\u6ffe\u6578\u64da<\/h2>\n<p>\u5728\u67e5\u8a62\u4e2d\u4f7f\u7528<code>WHERE<\/code>\u5b50\u53e5\u53ef\u4ee5\u5e6b\u52a9\u60a8\u904e\u6ffe\u51fa\u7b26\u5408\u7279\u5b9a\u689d\u4ef6\u7684\u6578\u64da\u3002\u4f8b\u5982\uff0c\u5982\u679c\u60a8\u53ea\u60f3\u67e5\u8a62\u5e74\u9f61\u5927\u65bc30\u7684\u54e1\u5de5\uff0c\u53ef\u4ee5\u9019\u6a23\u5beb\uff1a<\/p>\n<pre><code>SELECT * FROM employees\nWHERE age &gt; 30;<\/code><\/pre>\n<h2 id=\"%e9%81%b8%e6%93%87%e7%89%b9%e5%ae%9a%e5%88%97-ZKGMAePDxJ\">\u9078\u64c7\u7279\u5b9a\u5217<\/h2>\n<p>\u5982\u679c\u60a8\u53ea\u9700\u8981\u67e5\u8a62\u7279\u5b9a\u7684\u5217\uff0c\u53ef\u4ee5\u5728<code>SELECT<\/code>\u8a9e\u53e5\u4e2d\u6307\u5b9a\u9019\u4e9b\u5217\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT first_name, last_name FROM employees;<\/code><\/pre>\n<p>\u9019\u689d\u547d\u4ee4\u5c07\u50c5\u8fd4\u56de<code>first_name<\/code>\u548c<code>last_name<\/code>\u9019\u5169\u5217\u7684\u6578\u64da\u3002<\/p>\n<h2 id=\"%e6%8e%92%e5%ba%8f%e6%9f%a5%e8%a9%a2%e7%b5%90%e6%9e%9c-ZKGMAePDxJ\">\u6392\u5e8f\u67e5\u8a62\u7d50\u679c<\/h2>\n<p>\u4f7f\u7528<code>ORDER BY<\/code>\u5b50\u53e5\u53ef\u4ee5\u5c0d\u67e5\u8a62\u7d50\u679c\u9032\u884c\u6392\u5e8f\u3002\u9ed8\u8a8d\u60c5\u6cc1\u4e0b\uff0c\u6392\u5e8f\u662f\u5347\u5e8f\u7684\uff0c\u4f46\u60a8\u4e5f\u53ef\u4ee5\u6307\u5b9a\u964d\u5e8f\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT * FROM employees\nORDER BY last_name ASC;<\/code><\/pre>\n<p>\u9019\u689d\u547d\u4ee4\u5c07\u6839\u64da<code>last_name<\/code>\u5217\u7684\u5b57\u6bcd\u9806\u5e8f\u5347\u5e8f\u6392\u5217\u7d50\u679c\u3002\u5982\u679c\u8981\u964d\u5e8f\u6392\u5217\uff0c\u53ef\u4ee5\u4f7f\u7528<code>DESC<\/code>\uff1a<\/p>\n<pre><code>SELECT * FROM employees\nORDER BY last_name DESC;<\/code><\/pre>\n<h2 id=\"%e4%bd%bf%e7%94%a8limit%e9%99%90%e5%88%b6%e7%b5%90%e6%9e%9c%e6%95%b8%e9%87%8f-ZKGMAePDxJ\">\u4f7f\u7528LIMIT\u9650\u5236\u7d50\u679c\u6578\u91cf<\/h2>\n<p>\u5982\u679c\u60a8\u53ea\u60f3\u7372\u53d6\u67e5\u8a62\u7d50\u679c\u7684\u524d\u5e7e\u689d\u8a18\u9304\uff0c\u53ef\u4ee5\u4f7f\u7528<code>LIMIT<\/code>\u5b50\u53e5\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT * FROM employees\nLIMIT 5;<\/code><\/pre>\n<p>\u9019\u689d\u547d\u4ee4\u5c07\u50c5\u8fd4\u56de\u524d\u4e94\u689d\u8a18\u9304\u3002<\/p>\n<h2 id=\"%e7%b5%90%e5%90%88%e5%a4%9a%e5%80%8b%e6%a2%9d%e4%bb%b6-ZKGMAePDxJ\">\u7d50\u5408\u591a\u500b\u689d\u4ef6<\/h2>\n<p>\u60a8\u53ef\u4ee5\u4f7f\u7528<code>AND<\/code>\u548c<code>OR<\/code>\u4f86\u7d50\u5408\u591a\u500b\u67e5\u8a62\u689d\u4ef6\u3002\u4f8b\u5982\uff1a<\/p>\n<pre><code>SELECT * FROM employees\nWHERE age &gt; 30 AND department = 'Sales';<\/code><\/pre>\n<p>\u9019\u689d\u547d\u4ee4\u5c07\u8fd4\u56de\u5e74\u9f61\u5927\u65bc30\u4e14\u90e8\u9580\u70ba\u92b7\u552e\u7684\u6240\u6709\u54e1\u5de5\u3002<\/p>\n<h2 id=\"%e5%b0%8f%e7%b5%90-ZKGMAePDxJ\">\u5c0f\u7d50<\/h2>\n<p>\u4f7f\u7528<code>SELECT<\/code>\u547d\u4ee4\u67e5\u8a62\u93c8\u63a5\u6578\u64da\u5eab\u4e2d\u7684\u6578\u64da\u662f\u4e00\u9805\u57fa\u672c\u800c\u91cd\u8981\u7684\u6280\u80fd\u3002\u901a\u904e\u638c\u63e1\u57fa\u672c\u8a9e\u6cd5\u3001\u904e\u6ffe\u689d\u4ef6\u3001\u6392\u5e8f\u548c\u9650\u5236\u7d50\u679c\u7b49\u6280\u5de7\uff0c\u60a8\u53ef\u4ee5\u6709\u6548\u5730\u5f9e\u6578\u64da\u5eab\u4e2d\u63d0\u53d6\u6240\u9700\u7684\u4fe1\u606f\u3002\u7121\u8ad6\u662f\u5728\u958b\u767c\u61c9\u7528\u7a0b\u5e8f\u9084\u662f\u9032\u884c\u6578\u64da\u5206\u6790\uff0c<code>SELECT<\/code>\u547d\u4ee4\u90fd\u662f\u4e0d\u53ef\u6216\u7f3a\u7684\u5de5\u5177\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684\u6578\u64da\u5eab\u89e3\u6c7a\u65b9\u6848\uff0c\u8003\u616e\u4f7f\u7528<a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a>\u4f86\u6258\u7ba1\u60a8\u7684\u6578\u64da\u5eab\u3002\u900f\u904e\u7a69\u5b9a\u7684\u4f3a\u670d\u5668\u6027\u80fd\uff0c\u60a8\u53ef\u4ee5\u66f4\u8f15\u9b06\u5730\u7ba1\u7406\u548c\u67e5\u8a62\u6578\u64da\uff0c\u63d0\u5347\u696d\u52d9\u6548\u7387\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u5982\u4f55\u4f7f\u7528SELECT\u547d\u4ee4\u5728\u93c8\u63a5\u6578\u64da\u5eab\u4e2d\u67e5\u8a62\u6578\u64da\uff0c\u638c\u63e1\u57fa\u672c\u8a9e\u6cd5\u548c\u5be6\u7528\u6280\u5de7\uff0c\u63d0\u5347\u6578\u64da\u6aa2\u7d22\u6548\u7387\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-175387","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/175387","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=175387"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/175387\/revisions"}],"predecessor-version":[{"id":175388,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/175387\/revisions\/175388"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=175387"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=175387"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=175387"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}