{"id":143761,"date":"2024-11-01T01:01:20","date_gmt":"2024-10-31T17:01:20","guid":{"rendered":"https:\/\/server.hk\/cnblog\/143761\/"},"modified":"2024-11-01T01:01:21","modified_gmt":"2024-10-31T17:01:21","slug":"sql-%e6%9f%a5%e8%a9%a2%e5%84%aa%e5%8c%96%e5%af%a6%e4%be%8b%ef%bc%9a%e9%8a%80%e8%a1%8c%e6%a0%a1%e5%9c%92%e5%8d%a1%e7%b9%b3%e8%b2%bb%e7%9a%84%e6%80%a7%e8%83%bd%e5%84%aa%e5%8c%96","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/143761\/","title":{"rendered":"SQL \u67e5\u8a62\u512a\u5316\u5be6\u4f8b\uff1a\u9280\u884c\u6821\u5712\u5361\u7e73\u8cbb\u7684\u6027\u80fd\u512a\u5316"},"content":{"rendered":"<h1 id=\"sql-%e6%9f%a5%e8%a9%a2%e5%84%aa%e5%8c%96%e5%af%a6%e4%be%8b%ef%bc%9a%e9%8a%80%e8%a1%8c%e6%a0%a1%e5%9c%92%e5%8d%a1%e7%b9%b3%e8%b2%bb%e7%9a%84%e6%80%a7%e8%83%bd%e5%84%aa%e5%8c%96-mDWhaZFPQp\">SQL \u67e5\u8a62\u512a\u5316\u5be6\u4f8b\uff1a\u9280\u884c\u6821\u5712\u5361\u7e73\u8cbb\u7684\u6027\u80fd\u512a\u5316<\/h1>\n<p>\u5728\u7576\u4eca\u6578\u64da\u9a45\u52d5\u7684\u4e16\u754c\u4e2d\uff0cSQL \u67e5\u8a62\u7684\u6027\u80fd\u512a\u5316\u5c0d\u65bc\u4efb\u4f55\u4f9d\u8cf4\u6578\u64da\u5eab\u7684\u61c9\u7528\u7a0b\u5e8f\u90fd\u662f\u81f3\u95dc\u91cd\u8981\u7684\u3002\u7279\u5225\u662f\u5728\u9280\u884c\u6821\u5712\u5361\u7e73\u8cbb\u7cfb\u7d71\u4e2d\uff0c\u67e5\u8a62\u7684\u6548\u7387\u76f4\u63a5\u5f71\u97ff\u5230\u7528\u6236\u9ad4\u9a57\u548c\u7cfb\u7d71\u7684\u6574\u9ad4\u6027\u80fd\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5982\u4f55\u901a\u904e\u5be6\u969b\u6848\u4f8b\u4f86\u512a\u5316 SQL \u67e5\u8a62\uff0c\u4ee5\u63d0\u9ad8\u9280\u884c\u6821\u5712\u5361\u7e73\u8cbb\u7cfb\u7d71\u7684\u6027\u80fd\u3002<\/p>\n<h2 id=\"%e5%95%8f%e9%a1%8c%e8%83%8c%e6%99%af-mDWhaZFPQp\">\u554f\u984c\u80cc\u666f<\/h2>\n<p>\u9280\u884c\u6821\u5712\u5361\u7e73\u8cbb\u7cfb\u7d71\u901a\u5e38\u9700\u8981\u8655\u7406\u5927\u91cf\u7684\u4ea4\u6613\u6578\u64da\u3002\u7528\u6236\u5728\u7e73\u8cbb\u6642\uff0c\u7cfb\u7d71\u9700\u8981\u5feb\u901f\u67e5\u8a62\u7528\u6236\u7684\u8cec\u6236\u4fe1\u606f\u3001\u4ea4\u6613\u6b77\u53f2\u4ee5\u53ca\u53ef\u7528\u9918\u984d\u7b49\u3002\u96a8\u8457\u7528\u6236\u6578\u91cf\u7684\u589e\u52a0\uff0c\u67e5\u8a62\u6027\u80fd\u53ef\u80fd\u6703\u53d7\u5230\u5f71\u97ff\uff0c\u5c0e\u81f4\u7cfb\u7d71\u53cd\u61c9\u7de9\u6162\uff0c\u751a\u81f3\u51fa\u73fe\u8d85\u6642\u932f\u8aa4\u3002<\/p>\n<h2 id=\"%e6%80%a7%e8%83%bd%e7%93%b6%e9%a0%b8%e5%88%86%e6%9e%90-mDWhaZFPQp\">\u6027\u80fd\u74f6\u9838\u5206\u6790<\/h2>\n<p>\u5728\u9032\u884c\u6027\u80fd\u512a\u5316\u4e4b\u524d\uff0c\u9996\u5148\u9700\u8981\u8b58\u5225\u6027\u80fd\u74f6\u9838\u3002\u5e38\u898b\u7684\u6027\u80fd\u554f\u984c\u5305\u62ec\uff1a<\/p>\n<ul>\n<li>\u672a\u4f7f\u7528\u7d22\u5f15\u7684\u67e5\u8a62<\/li>\n<li>\u8907\u96dc\u7684\u806f\u63a5\u64cd\u4f5c<\/li>\n<li>\u4e0d\u5fc5\u8981\u7684\u6578\u64da\u6aa2\u7d22<\/li>\n<li>\u7f3a\u4e4f\u67e5\u8a62\u7de9\u5b58<\/li>\n<\/ul>\n<p>\u901a\u904e\u4f7f\u7528 SQL \u7684\u57f7\u884c\u8a08\u5283\u5206\u6790\u5de5\u5177\uff0c\u53ef\u4ee5\u627e\u51fa\u54ea\u4e9b\u67e5\u8a62\u6700\u8017\u6642\uff0c\u4e26\u91dd\u5c0d\u6027\u5730\u9032\u884c\u512a\u5316\u3002<\/p>\n<h2 id=\"%e5%84%aa%e5%8c%96%e5%af%a6%e4%be%8b-mDWhaZFPQp\">\u512a\u5316\u5be6\u4f8b<\/h2>\n<h3 id=\"1-%e4%bd%bf%e7%94%a8%e7%b4%a2%e5%bc%95-mDWhaZFPQp\">1. \u4f7f\u7528\u7d22\u5f15<\/h3>\n<p>\u7d22\u5f15\u662f\u63d0\u9ad8\u67e5\u8a62\u6027\u80fd\u7684\u6709\u6548\u624b\u6bb5\u3002\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u7528\u6236\u8868\u548c\u4e00\u500b\u4ea4\u6613\u8868\uff0c\u67e5\u8a62\u7528\u6236\u7684\u4ea4\u6613\u6b77\u53f2\u6642\uff0c\u672a\u4f7f\u7528\u7d22\u5f15\u7684\u67e5\u8a62\u53ef\u80fd\u5982\u4e0b\uff1a<\/p>\n<pre><code>SELECT * FROM transactions WHERE user_id = 12345;<\/code><\/pre>\n<p>\u5728\u9019\u7a2e\u60c5\u6cc1\u4e0b\uff0c\u70ba <code>user_id<\/code> \u5217\u5275\u5efa\u7d22\u5f15\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u67e5\u8a62\u901f\u5ea6\uff1a<\/p>\n<pre><code>CREATE INDEX idx_user_id ON transactions(user_id);<\/code><\/pre>\n<h3 id=\"2-%e7%b0%a1%e5%8c%96%e6%9f%a5%e8%a9%a2-mDWhaZFPQp\">2. \u7c21\u5316\u67e5\u8a62<\/h3>\n<p>\u8907\u96dc\u7684\u67e5\u8a62\u53ef\u80fd\u6703\u5c0e\u81f4\u6027\u80fd\u4e0b\u964d\u3002\u53ef\u4ee5\u901a\u904e\u7c21\u5316\u67e5\u8a62\u4f86\u63d0\u9ad8\u6548\u7387\u3002\u4f8b\u5982\uff0c\u4ee5\u4e0b\u67e5\u8a62\u540c\u6642\u6aa2\u7d22\u7528\u6236\u4fe1\u606f\u548c\u4ea4\u6613\u8a18\u9304\uff1a<\/p>\n<pre><code>SELECT u.name, t.amount FROM users u JOIN transactions t ON u.id = t.user_id WHERE u.id = 12345;<\/code><\/pre>\n<p>\u5982\u679c\u53ea\u9700\u8981\u7528\u6236\u7684\u540d\u7a31\u548c\u6700\u8fd1\u7684\u4ea4\u6613\u91d1\u984d\uff0c\u53ef\u4ee5\u4f7f\u7528\u5b50\u67e5\u8a62\u4f86\u7c21\u5316\uff1a<\/p>\n<pre><code>SELECT u.name, (SELECT amount FROM transactions WHERE user_id = 12345 ORDER BY date DESC LIMIT 1) AS last_amount FROM users u WHERE u.id = 12345;<\/code><\/pre>\n<h3 id=\"3-%e4%bd%bf%e7%94%a8%e6%9f%a5%e8%a9%a2%e7%b7%a9%e5%ad%98-mDWhaZFPQp\">3. \u4f7f\u7528\u67e5\u8a62\u7de9\u5b58<\/h3>\n<p>\u67e5\u8a62\u7de9\u5b58\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u91cd\u8907\u67e5\u8a62\u7684\u6027\u80fd\u3002\u5c0d\u65bc\u7d93\u5e38\u67e5\u8a62\u7684\u6578\u64da\uff0c\u53ef\u4ee5\u8003\u616e\u4f7f\u7528\u7de9\u5b58\u6280\u8853\u3002\u4f8b\u5982\uff0c\u4f7f\u7528 Redis \u6216 Memcached \u5c07\u67e5\u8a62\u7d50\u679c\u7de9\u5b58\u8d77\u4f86\uff0c\u6e1b\u5c11\u5c0d\u6578\u64da\u5eab\u7684\u76f4\u63a5\u67e5\u8a62\u3002<\/p>\n<h2 id=\"%e6%b8%ac%e8%a9%a6%e8%88%87%e7%9b%a3%e6%8e%a7-mDWhaZFPQp\">\u6e2c\u8a66\u8207\u76e3\u63a7<\/h2>\n<p>\u5728\u9032\u884c\u512a\u5316\u5f8c\uff0c\u5fc5\u9808\u9032\u884c\u6e2c\u8a66\u4ee5\u78ba\u4fdd\u6027\u80fd\u7684\u63d0\u5347\u3002\u53ef\u4ee5\u4f7f\u7528\u5de5\u5177\u5982 Apache JMeter \u9032\u884c\u58d3\u529b\u6e2c\u8a66\uff0c\u4e26\u76e3\u63a7\u7cfb\u7d71\u7684\u97ff\u61c9\u6642\u9593\u548c\u8cc7\u6e90\u4f7f\u7528\u60c5\u6cc1\u3002\u5b9a\u671f\u7684\u6027\u80fd\u76e3\u63a7\u53ef\u4ee5\u5e6b\u52a9\u53ca\u6642\u767c\u73fe\u65b0\u7684\u74f6\u9838\uff0c\u4e26\u9032\u884c\u76f8\u61c9\u7684\u512a\u5316\u3002<\/p>\n<h2 id=\"%e7%b8%bd%e7%b5%90-mDWhaZFPQp\">\u7e3d\u7d50<\/h2>\n<p>SQL \u67e5\u8a62\u7684\u6027\u80fd\u512a\u5316\u662f\u4e00\u500b\u6301\u7e8c\u7684\u904e\u7a0b\uff0c\u7279\u5225\u662f\u5728\u9280\u884c\u6821\u5712\u5361\u7e73\u8cbb\u7cfb\u7d71\u9019\u6a23\u7684\u9ad8\u8ca0\u8f09\u74b0\u5883\u4e2d\u3002\u901a\u904e\u4f7f\u7528\u7d22\u5f15\u3001\u7c21\u5316\u67e5\u8a62\u548c\u67e5\u8a62\u7de9\u5b58\u7b49\u6280\u8853\uff0c\u53ef\u4ee5\u986f\u8457\u63d0\u9ad8\u7cfb\u7d71\u7684\u6027\u80fd\u548c\u7528\u6236\u9ad4\u9a57\u3002\u96a8\u8457\u7528\u6236\u9700\u6c42\u7684\u8b8a\u5316\uff0c\u6301\u7e8c\u7684\u76e3\u63a7\u548c\u512a\u5316\u5c07\u662f\u78ba\u4fdd\u7cfb\u7d71\u7a69\u5b9a\u904b\u884c\u7684\u95dc\u9375\u3002<\/p>\n<p>\u5982\u9700\u4e86\u89e3\u66f4\u591a\u6709\u95dc <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u548c\u6578\u64da\u5eab\u6027\u80fd\u512a\u5316\u7684\u8cc7\u8a0a\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u63a2\u7d22\u9280\u884c\u6821\u5712\u5361\u7e73\u8cbb\u7684SQL\u67e5\u8a62\u512a\u5316\u5be6\u4f8b\uff0c\u63d0\u5347\u6027\u80fd\uff0c\u6e1b\u5c11\u67e5\u8a62\u6642\u9593\uff0c\u589e\u5f37\u7528\u6236\u9ad4\u9a57\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-143761","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/143761","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=143761"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/143761\/revisions"}],"predecessor-version":[{"id":143762,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/143761\/revisions\/143762"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=143761"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=143761"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=143761"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}