{"id":5865,"date":"2024-11-14T08:15:05","date_gmt":"2024-11-14T00:15:05","guid":{"rendered":"https:\/\/fwq.ai\/blog\/5865\/"},"modified":"2024-11-14T08:15:05","modified_gmt":"2024-11-14T00:15:05","slug":"sql%e5%ad%90%e6%9f%a5%e8%af%a2%e6%80%8e%e4%b9%88%e5%ae%9e%e7%8e%b0","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/5865\/","title":{"rendered":"sql\u5b50\u67e5\u8be2\u600e\u4e48\u5b9e\u73b0"},"content":{"rendered":"<blockquote><p>\n  \u5b9e\u73b0 sql \u5b50\u67e5\u8be2\u7684\u6b65\u9aa4\uff1a\u786e\u5b9a\u5b50\u67e5\u8be2\u7684\u76ee\u7684\uff1a\u68c0\u7d22\u6240\u9700\u6570\u636e\u3002\u7f16\u5199\u5b50\u67e5\u8be2\uff1a\u4f7f\u7528 select \u8bed\u53e5\u68c0\u7d22\u5217\u548c\u7b5b\u9009\u6761\u4ef6\u3002\u5d4c\u5165\u5b50\u67e5\u8be2\uff1a\u5c06\u5b50\u67e5\u8be2\u62ec\u5728\u4e3b\u67e5\u8be2\u4e2d\u4f5c\u4e3a\u6761\u4ef6\u6216\u8fd0\u7b97\u7b26\u3002\u8fde\u63a5\u5b50\u67e5\u8be2\uff1a\u4f7f\u7528\u5173\u7cfb\u8fd0\u7b97\u7b26\u8fde\u63a5\u5b50\u67e5\u8be2\u548c\u4e3b\u67e5\u8be2\u7684\u5217\u6216\u6761\u4ef6\u3002\u6267\u884c\u67e5\u8be2\uff1a\u68c0\u7d22\u6570\u636e\u3002\n<\/p><\/blockquote>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/article\/202406\/03\/2024060321094339178.jpg\" class=\"aligncenter\" title=\"sql\u5b50\u67e5\u8be2\u600e\u4e48\u5b9e\u73b0\u63d2\u56fe\" alt=\"sql\u5b50\u67e5\u8be2\u600e\u4e48\u5b9e\u73b0\u63d2\u56fe\" \/><\/p>\n<p><strong>SQL \u5b50\u67e5\u8be2\u7684\u5b9e\u73b0<\/strong><\/p>\n<p>\u5b50\u67e5\u8be2\u662f\u4e00\u79cd\u5d4c\u5957\u5728\u4e3b\u67e5\u8be2\u5185\u90e8\u7684\u67e5\u8be2\u3002\u5b83\u5141\u8bb8\u6211\u4eec\u4ece\u4e00\u4e2a\u6216\u591a\u4e2a\u8868\u4e2d\u68c0\u7d22\u6570\u636e\uff0c\u5e76\u5c06\u7ed3\u679c\u4f5c\u4e3a\u4e3b\u67e5\u8be2\u4e2d\u7684\u6761\u4ef6\u6216\u8fd0\u7b97\u7b26\u4f7f\u7528\u3002\u5b50\u67e5\u8be2\u53ef\u4ee5\u4f7f\u7528\u4e0d\u540c\u7684\u5173\u7cfb\u8fd0\u7b97\u7b26\uff08\u4f8b\u5982 =\u3001&gt;\u3001<\/p>\n<p><strong>\u5b9e\u73b0\u5b50\u67e5\u8be2\u7684\u6b65\u9aa4\uff1a<\/strong><\/p>\n<ol>\n<li> <strong>\u786e\u5b9a\u5b50\u67e5\u8be2\u7684\u76ee\u7684\uff1a<\/strong>\u786e\u5b9a\u8981\u4f7f\u7528\u5b50\u67e5\u8be2\u6765\u68c0\u7d22\u54ea\u4e9b\u6570\u636e\u3002<\/li>\n<li> <strong>\u7f16\u5199\u5b50\u67e5\u8be2\uff1a<\/strong>\u4f7f\u7528 SELECT \u8bed\u53e5\u7f16\u5199\u5b50\u67e5\u8be2\uff0c\u5c31\u50cf\u7f16\u5199\u666e\u901a\u67e5\u8be2\u4e00\u6837\u3002\u5b83\u9700\u8981\u5305\u542b\u8981\u68c0\u7d22\u7684\u5217\u548c\u7b5b\u9009\u6761\u4ef6\u3002<\/li>\n<li> <strong>\u5c06\u5b50\u67e5\u8be2\u5d4c\u5165\u4e3b\u67e5\u8be2\uff1a<\/strong>\u5c06\u5b50\u67e5\u8be2\u5d4c\u5165\u4e3b\u67e5\u8be2\u4e2d\uff0c\u4f7f\u5176\u6210\u4e3a\u4e00\u4e2a\u6761\u4ef6\u6216\u8fd0\u7b97\u7b26\u3002\u5b50\u67e5\u8be2\u901a\u5e38\u7528\u62ec\u53f7\u62ec\u8d77\u6765\u3002<\/li>\n<li> <strong>\u8fde\u63a5\u5b50\u67e5\u8be2\u548c\u4e3b\u67e5\u8be2\uff1a<\/strong>\u4f7f\u7528\u9002\u5f53\u7684\u5173\u7cfb\u8fd0\u7b97\u7b26\u5c06\u5b50\u67e5\u8be2\u4e0e\u4e3b\u67e5\u8be2\u7684\u5217\u6216\u6761\u4ef6\u8fde\u63a5\u8d77\u6765\u3002<\/li>\n<li> <strong>\u6267\u884c\u67e5\u8be2\uff1a<\/strong>\u6267\u884c\u6574\u4e2a\u67e5\u8be2\u4ee5\u68c0\u7d22\u6570\u636e\u3002<\/li>\n<\/ol>\n<p><strong>\u793a\u4f8b\uff1a<\/strong><\/p>\n<p>\u5047\u8bbe\u6211\u4eec\u6709\u4e00\u4e2a\u540d\u4e3a &#8220;employees&#8221; \u7684\u8868\uff0c\u5176\u4e2d\u5305\u542b\u5458\u5de5\u4fe1\u606f\uff0c\u5305\u62ec\u5458\u5de5 ID\u3001\u59d3\u540d\u548c\u90e8\u95e8 ID\u3002\u6211\u4eec\u8981\u627e\u51fa\u5c5e\u4e8e\u90e8\u95e8 ID \u4e3a 10 \u7684\u6240\u6709\u5458\u5de5\u7684\u59d3\u540d\u3002<\/p>\n<p><strong>\u4e3b\u67e5\u8be2\uff1a<\/strong><\/p>\n<pre>SELECT name\nFROM employees<\/pre>\n<p>  \u767b\u5f55\u540e\u590d\u5236   <\/p>\n<p><strong>\u5b50\u67e5\u8be2\uff1a<\/strong><\/p>\n<pre>(SELECT department_id FROM employees WHERE department_id = 10)<\/pre>\n<p>  \u767b\u5f55\u540e\u590d\u5236   <\/p>\n<p><strong>\u5b8c\u6574\u67e5\u8be2\uff1a<\/strong><\/p>\n<pre>SELECT name\nFROM employees\nWHERE department_id IN (SELECT department_id FROM employees WHERE department_id = 10)<\/pre>\n<p>  \u767b\u5f55\u540e\u590d\u5236   <\/p>\n<p>\u5728\u4e0a\u9762\u7684\u793a\u4f8b\u4e2d\uff0c\u5b50\u67e5\u8be2\u68c0\u7d22\u4e86\u90e8\u95e8 ID \u4e3a 10 \u7684\u5458\u5de5\u7684\u90e8\u95e8 ID\u3002\u4e3b\u67e5\u8be2\u4f7f\u7528\u5b50\u67e5\u8be2\u7684\u7ed3\u679c\u6765\u7b5b\u9009\u51fa\u59d3\u540d\u5217\u3002\u6700\u7ec8\u7684\u7ed3\u679c\u5c06\u53ea\u5305\u542b\u5c5e\u4e8e\u90e8\u95e8 ID \u4e3a 10 \u7684\u5458\u5de5\u7684\u59d3\u540d\u3002<\/p>\n<p>\u4ee5\u4e0a\u5c31\u662fsql\u5b50\u67e5\u8be2\u600e\u4e48\u5b9e\u73b0\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u7f51\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b9e\u73b0 sql \u5b50\u67e5\u8be2\u7684\u6b65\u9aa4\uff1a\u786e\u5b9a\u5b50\u67e5\u8be2\u7684\u76ee\u7684\uff1a\u68c0\u7d22\u6240\u9700\u6570\u636e\u3002\u7f16\u5199\u5b50\u67e5\u8be2\uff1a\u4f7f\u7528 select \u8bed\u53e5\u68c0\u7d22\u5217\u548c\u7b5b\u9009\u6761\u4ef6\u3002\u5d4c\u5165\u5b50\u67e5\u8be2\uff1a\u5c06\u5b50\u67e5\u8be2\u62ec\u5728\u4e3b\u67e5\u8be2\u4e2d\u4f5c\u4e3a\u6761\u4ef6\u6216\u8fd0\u7b97\u7b26\u3002\u8fde\u63a5\u5b50\u67e5\u8be2\uff1a\u4f7f\u7528\u5173\u7cfb\u8fd0\u7b97\u7b26\u8fde\u63a5\u5b50\u67e5\u8be2\u548c\u4e3b\u67e5\u8be2\u7684\u5217\u6216\u6761\u4ef6\u3002\u6267\u884c\u67e5\u8be2\uff1a\u68c0\u7d22\u6570\u636e\u3002 SQL \u5b50\u67e5\u8be2\u7684\u5b9e\u73b0 \u5b50\u67e5\u8be2\u662f\u4e00\u79cd\u5d4c\u5957\u5728\u4e3b\u67e5\u8be2\u5185\u90e8\u7684\u67e5\u8be2\u3002\u5b83\u5141\u8bb8\u6211\u4eec\u4ece\u4e00\u4e2a\u6216\u591a\u4e2a\u8868\u4e2d\u68c0\u7d22\u6570\u636e\uff0c\u5e76\u5c06\u7ed3\u679c\u4f5c\u4e3a\u4e3b\u67e5\u8be2\u4e2d\u7684\u6761\u4ef6\u6216\u8fd0\u7b97\u7b26\u4f7f\u7528\u3002\u5b50\u67e5\u8be2\u53ef\u4ee5\u4f7f\u7528\u4e0d\u540c\u7684\u5173\u7cfb\u8fd0\u7b97\u7b26\uff08\u4f8b\u5982 =\u3001&gt;\u3001 \u5b9e\u73b0\u5b50\u67e5\u8be2\u7684\u6b65\u9aa4\uff1a \u786e\u5b9a\u5b50\u67e5\u8be2\u7684\u76ee\u7684\uff1a\u786e\u5b9a\u8981\u4f7f\u7528\u5b50\u67e5\u8be2\u6765\u68c0\u7d22\u54ea\u4e9b\u6570\u636e\u3002 \u7f16\u5199\u5b50\u67e5\u8be2\uff1a\u4f7f\u7528 SELECT \u8bed\u53e5\u7f16\u5199\u5b50\u67e5\u8be2\uff0c\u5c31\u50cf\u7f16\u5199\u666e\u901a\u67e5\u8be2\u4e00\u6837\u3002\u5b83\u9700\u8981\u5305\u542b\u8981\u68c0\u7d22\u7684\u5217\u548c\u7b5b\u9009\u6761\u4ef6\u3002 \u5c06\u5b50\u67e5\u8be2\u5d4c\u5165\u4e3b\u67e5\u8be2\uff1a\u5c06\u5b50\u67e5\u8be2\u5d4c\u5165\u4e3b\u67e5\u8be2\u4e2d\uff0c\u4f7f\u5176\u6210\u4e3a\u4e00\u4e2a\u6761\u4ef6\u6216\u8fd0\u7b97\u7b26\u3002\u5b50\u67e5\u8be2\u901a\u5e38\u7528\u62ec\u53f7\u62ec\u8d77\u6765\u3002 \u8fde\u63a5\u5b50\u67e5\u8be2\u548c\u4e3b\u67e5\u8be2\uff1a\u4f7f\u7528\u9002\u5f53\u7684\u5173\u7cfb\u8fd0\u7b97\u7b26\u5c06\u5b50\u67e5\u8be2\u4e0e\u4e3b\u67e5\u8be2\u7684\u5217\u6216\u6761\u4ef6\u8fde\u63a5\u8d77\u6765\u3002 \u6267\u884c\u67e5\u8be2\uff1a\u6267\u884c\u6574\u4e2a\u67e5\u8be2\u4ee5\u68c0\u7d22\u6570\u636e\u3002 \u793a\u4f8b\uff1a \u5047\u8bbe\u6211\u4eec\u6709\u4e00\u4e2a\u540d\u4e3a &#8220;employees&#8221; \u7684\u8868\uff0c\u5176\u4e2d\u5305\u542b\u5458\u5de5\u4fe1\u606f\uff0c\u5305\u62ec\u5458\u5de5 ID\u3001\u59d3\u540d\u548c\u90e8\u95e8 ID\u3002\u6211\u4eec\u8981\u627e\u51fa\u5c5e\u4e8e\u90e8\u95e8 ID \u4e3a 10 \u7684\u6240\u6709\u5458\u5de5\u7684\u59d3\u540d\u3002 \u4e3b\u67e5\u8be2\uff1a SELECT name FROM employees \u767b\u5f55\u540e\u590d\u5236 \u5b50\u67e5\u8be2\uff1a (SELECT department_id FROM employees WHERE department_id = 10) \u767b\u5f55\u540e\u590d\u5236 \u5b8c\u6574\u67e5\u8be2\uff1a SELECT name FROM employees WHERE department_id IN (SELECT department_id FROM employees [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-5865","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5865","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=5865"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/5865\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=5865"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=5865"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=5865"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}