{"id":143895,"date":"2024-11-01T02:09:20","date_gmt":"2024-10-31T18:09:20","guid":{"rendered":"https:\/\/server.hk\/cnblog\/143895\/"},"modified":"2024-11-01T02:09:21","modified_gmt":"2024-10-31T18:09:21","slug":"sql-%e5%88%aa%e9%99%a4%e6%95%b8%e6%93%9a%e7%9a%84%e4%b8%8d%e5%90%8c%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/143895\/","title":{"rendered":"SQL \u522a\u9664\u6578\u64da\u7684\u4e0d\u540c\u65b9\u6cd5"},"content":{"rendered":"<h1 id=\"sql-%e5%88%aa%e9%99%a4%e6%95%b8%e6%93%9a%e7%9a%84%e4%b8%8d%e5%90%8c%e6%96%b9%e6%b3%95-ojIWPYLecS\">SQL \u522a\u9664\u6578\u64da\u7684\u4e0d\u540c\u65b9\u6cd5<\/h1>\n<p>\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u522a\u9664\u6578\u64da\u662f\u4e00\u500b\u5e38\u898b\u7684\u64cd\u4f5c\u3002SQL\uff08\u7d50\u69cb\u5316\u67e5\u8a62\u8a9e\u8a00\uff09\u63d0\u4f9b\u4e86\u591a\u7a2e\u65b9\u6cd5\u4f86\u522a\u9664\u6578\u64da\uff0c\u9019\u4e9b\u65b9\u6cd5\u5404\u6709\u5176\u7279\u9ede\u548c\u9069\u7528\u5834\u666f\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5e7e\u7a2e\u5e38\u898b\u7684 SQL \u522a\u9664\u6578\u64da\u7684\u65b9\u6cd5\uff0c\u4e26\u63d0\u4f9b\u76f8\u61c9\u7684\u793a\u4f8b\u4ee3\u78bc\u3002<\/p>\n<h2 id=\"1-%e4%bd%bf%e7%94%a8-delete-%e8%aa%9e%e5%8f%a5-ojIWPYLecS\">1. \u4f7f\u7528 DELETE \u8a9e\u53e5<\/h2>\n<p>\u6700\u57fa\u672c\u7684\u522a\u9664\u6578\u64da\u65b9\u6cd5\u662f\u4f7f\u7528 <code>DELETE<\/code> \u8a9e\u53e5\u3002\u9019\u500b\u8a9e\u53e5\u53ef\u4ee5\u6839\u64da\u6307\u5b9a\u7684\u689d\u4ef6\u522a\u9664\u4e00\u689d\u6216\u591a\u689d\u8a18\u9304\u3002<\/p>\n<pre><code>DELETE FROM \u8868\u540d WHERE \u689d\u4ef6;<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u540d\u70ba <code>employees<\/code> \u7684\u8868\uff0c\u4e26\u5e0c\u671b\u522a\u9664\u6240\u6709\u5e74\u9f61\u5927\u65bc 60 \u7684\u54e1\u5de5\u8a18\u9304\uff1a<\/p>\n<pre><code>DELETE FROM employees WHERE age &gt; 60;<\/code><\/pre>\n<p>\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0c\u5982\u679c\u4e0d\u52a0 <code>WHERE<\/code> \u689d\u4ef6\uff0c\u5247\u6703\u522a\u9664\u6574\u500b\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\uff1a<\/p>\n<pre><code>DELETE FROM employees;<\/code><\/pre>\n<h2 id=\"2-%e4%bd%bf%e7%94%a8-truncate-%e8%aa%9e%e5%8f%a5-ojIWPYLecS\">2. \u4f7f\u7528 TRUNCATE \u8a9e\u53e5<\/h2>\n<p>\u5982\u679c\u9700\u8981\u522a\u9664\u6574\u500b\u8868\u4e2d\u7684\u6240\u6709\u6578\u64da\uff0c\u4f46\u4e0d\u9700\u8981\u8a18\u9304\u522a\u9664\u7684\u65e5\u8a8c\uff0c\u53ef\u4ee5\u4f7f\u7528 <code>TRUNCATE<\/code> \u8a9e\u53e5\u3002\u9019\u500b\u8a9e\u53e5\u6bd4 <code>DELETE<\/code> \u66f4\u5feb\uff0c\u56e0\u70ba\u5b83\u4e0d\u6703\u9010\u884c\u522a\u9664\u6578\u64da\uff0c\u800c\u662f\u76f4\u63a5\u91cb\u653e\u6574\u500b\u8868\u7684\u7a7a\u9593\u3002<\/p>\n<pre><code>TRUNCATE TABLE \u8868\u540d;<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u522a\u9664 <code>employees<\/code> \u8868\u4e2d\u7684\u6240\u6709\u6578\u64da\uff1a<\/p>\n<pre><code>TRUNCATE TABLE employees;<\/code><\/pre>\n<p>\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0c<code>TRUNCATE<\/code> \u4e0d\u80fd\u8207 <code>WHERE<\/code> \u5b50\u53e5\u4e00\u8d77\u4f7f\u7528\uff0c\u4e26\u4e14\u5728\u67d0\u4e9b\u6578\u64da\u5eab\u4e2d\uff0c\u9019\u500b\u64cd\u4f5c\u662f\u4e0d\u53ef\u9006\u7684\u3002<\/p>\n<h2 id=\"3-%e4%bd%bf%e7%94%a8-drop-%e8%aa%9e%e5%8f%a5-ojIWPYLecS\">3. \u4f7f\u7528 DROP \u8a9e\u53e5<\/h2>\n<p>\u5982\u679c\u9700\u8981\u5b8c\u5168\u522a\u9664\u4e00\u500b\u8868\u53ca\u5176\u6240\u6709\u6578\u64da\uff0c\u53ef\u4ee5\u4f7f\u7528 <code>DROP<\/code> \u8a9e\u53e5\u3002\u9019\u5c07\u6c38\u4e45\u522a\u9664\u8868\u53ca\u5176\u7d50\u69cb\uff0c\u7121\u6cd5\u6062\u5fa9\u3002<\/p>\n<pre><code>DROP TABLE \u8868\u540d;<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u522a\u9664 <code>employees<\/code> \u8868\uff1a<\/p>\n<pre><code>DROP TABLE employees;<\/code><\/pre>\n<h2 id=\"4-%e4%bd%bf%e7%94%a8-join-%e5%88%aa%e9%99%a4%e6%95%b8%e6%93%9a-ojIWPYLecS\">4. \u4f7f\u7528 JOIN \u522a\u9664\u6578\u64da<\/h2>\n<p>\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u53ef\u80fd\u9700\u8981\u6839\u64da\u53e6\u4e00\u500b\u8868\u7684\u6578\u64da\u4f86\u522a\u9664\u8a18\u9304\u3002\u9019\u6642\u53ef\u4ee5\u4f7f\u7528 <code>JOIN<\/code> \u4f86\u5be6\u73fe\u3002<\/p>\n<pre><code>DELETE t1 FROM \u88681 t1\nJOIN \u88682 t2 ON t1.id = t2.id\nWHERE \u689d\u4ef6;<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u5047\u8a2d\u6211\u5011\u6709\u5169\u500b\u8868 <code>employees<\/code> \u548c <code>departments<\/code>\uff0c\u6211\u5011\u5e0c\u671b\u522a\u9664\u6240\u6709\u5728\u7279\u5b9a\u90e8\u9580\u7684\u54e1\u5de5\uff1a<\/p>\n<pre><code>DELETE e FROM employees e\nJOIN departments d ON e.department_id = d.id\nWHERE d.name = 'Sales';<\/code><\/pre>\n<h2 id=\"5-%e4%bd%bf%e7%94%a8%e5%ad%90%e6%9f%a5%e8%a9%a2%e5%88%aa%e9%99%a4%e6%95%b8%e6%93%9a-ojIWPYLecS\">5. \u4f7f\u7528\u5b50\u67e5\u8a62\u522a\u9664\u6578\u64da<\/h2>\n<p>\u5b50\u67e5\u8a62\u4e5f\u53ef\u4ee5\u7528\u65bc\u522a\u9664\u6578\u64da\uff0c\u9019\u7a2e\u65b9\u6cd5\u5141\u8a31\u5728 <code>DELETE<\/code> \u8a9e\u53e5\u4e2d\u5d4c\u5165\u53e6\u4e00\u500b\u67e5\u8a62\u3002<\/p>\n<pre><code>DELETE FROM \u8868\u540d\nWHERE id IN (SELECT id FROM \u53e6\u4e00\u500b\u8868 WHERE \u689d\u4ef6);<\/code><\/pre>\n<p>\u4f8b\u5982\uff0c\u522a\u9664\u6240\u6709\u5728 <code>employees<\/code> \u8868\u4e2d\u5e74\u9f61\u5927\u65bc 60 \u7684\u54e1\u5de5\uff1a<\/p>\n<pre><code>DELETE FROM employees\nWHERE id IN (SELECT id FROM employees WHERE age &gt; 60);<\/code><\/pre>\n<h2 id=\"%e7%b8%bd%e7%b5%90-ojIWPYLecS\">\u7e3d\u7d50<\/h2>\n<p>\u5728 SQL \u4e2d\uff0c\u522a\u9664\u6578\u64da\u7684\u65b9\u6cd5\u591a\u7a2e\u591a\u6a23\uff0c\u5305\u62ec\u4f7f\u7528 <code>DELETE<\/code>\u3001<code>TRUNCATE<\/code>\u3001<code>DROP<\/code>\u3001<code>JOIN<\/code> \u548c\u5b50\u67e5\u8a62\u7b49\u3002\u6bcf\u7a2e\u65b9\u6cd5\u90fd\u6709\u5176\u7279\u5b9a\u7684\u7528\u9014\u548c\u9650\u5236\uff0c\u9078\u64c7\u5408\u9069\u7684\u65b9\u6cd5\u53ef\u4ee5\u63d0\u9ad8\u6578\u64da\u7ba1\u7406\u7684\u6548\u7387\u548c\u5b89\u5168\u6027\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u6578\u64da\u8655\u7406\u7684\u7528\u6236\uff0c\u9078\u64c7\u5408\u9069\u7684 <a href=\"https:\/\/server.hk\">VPS<\/a> \u89e3\u6c7a\u65b9\u6848\u53ef\u4ee5\u63d0\u4f9b\u66f4\u597d\u7684\u6027\u80fd\u548c\u9748\u6d3b\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u63a2\u7d22 SQL \u522a\u9664\u6578\u64da\u7684\u4e0d\u540c\u65b9\u6cd5\uff0c\u5305\u62ec DELETE\u3001TRUNCATE \u548c DROP\uff0c\u4e86\u89e3\u5404\u81ea\u7684\u7528\u9014\u548c\u6027\u80fd\u5dee\u7570\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-143895","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/143895","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=143895"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/143895\/revisions"}],"predecessor-version":[{"id":143896,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/143895\/revisions\/143896"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=143895"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=143895"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=143895"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}