{"id":10020384,"date":"2024-11-07T12:12:04","date_gmt":"2024-11-07T04:12:04","guid":{"rendered":"https:\/\/itmax.cn\/?p=10020384"},"modified":"2024-11-07T12:12:04","modified_gmt":"2024-11-07T04:12:04","slug":"%e5%bf%85%e7%9f%a5%e5%bf%85%e4%bc%9a%ef%bc%81mysql%e7%b4%a2%e5%bc%95%e4%b8%8b%e6%8e%a8%ef%bc%9a%e5%8e%9f%e7%90%86%e4%b8%8e%e5%ae%9e%e6%88%98","status":"publish","type":"post","link":"https:\/\/itmax.cn\/?p=10020384","title":{"rendered":"\u5fc5\u77e5\u5fc5\u4f1a\uff01MySQL\u7d22\u5f15\u4e0b\u63a8\uff1a\u539f\u7406\u4e0e\u5b9e\u6218"},"content":{"rendered":"

\u7d22\u5f15\u4e0b\u63a8\u662f\u4ece MySQL5.6 \u5f00\u59cb\u5f15\u5165\u4e00\u4e2a\u7279\u6027\uff0c\u82f1\u6587\u662f index condition pushdown<\/code>\uff0c\u4e00\u822c\u7b80\u79f0\u4e3a ICP<\/code>\uff0c\u7d22\u5f15\u4e0b\u63a8\u901a\u8fc7\u51cf\u5c11\u56de\u8868\u7684\u6b21\u6570\uff0c\u6765\u63d0\u9ad8\u6570\u636e\u5e93\u7684\u67e5\u8be2\u6548\u7387\u3002<\/p>\n

\u6709\u7684\u5c0f\u4f19\u4f34\u53ef\u80fd\u4e5f\u770b\u8fc7\u4e00\u4e9b\u5173\u4e8e ICP \u7684\u6982\u5ff5\uff0c\u4f46\u662f\u6211\u89c9\u5f97\uff0c\u6982\u5ff5\u6bd4\u8f83\u7b80\u5355\uff0c\u8bf4\u4e00\u4e0b\u5f88\u5bb9\u6613\u61c2\uff0c\u4f46\u662f\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0c\u5404\u79cd\u5404\u6837\u7684\u60c5\u51b5\u975e\u5e38\u591a\u3002\u6240\u4ee5\u63a5\u4e0b\u6765\u7684\u5185\u5bb9\u6211\u60f3\u901a\u8fc7\u51e0\u4e2a\u5177\u4f53\u7684\u67e5\u8be2\u5206\u6790\u6765\u548c\u5927\u5bb6\u5206\u4eab ICP \u5230\u5e95\u662f\u600e\u4e48\u4e00\u56de\u4e8b\u3002<\/p>\n

\u4e00 \u7d22\u5f15\u4e0b\u63a8<\/h2>\n

\u4e3a\u4e86\u7ed9\u5927\u5bb6\u6f14\u793a\u7d22\u5f15\u4e0b\u63a8\uff0c\u6211\u7528 docker \u5b89\u88c5\u4e86\u4e24\u4e2a MySQL\uff0c\u4e00\u4e2a\u662f MySQL5.5.62\uff0c\u53e6\u4e00\u4e2a\u662f 5.7.26\uff0c\u56e0\u4e3a\u7d22\u5f15\u4e0b\u63a8\u662f MySQL5.6 \u4e2d\u5f00\u59cb\u5f15\u5165\u7684\u65b0\u7279\u6027\uff0c\u6240\u4ee5\u8fd9\u4e24\u4e2a\u7248\u672c\u5c31\u53ef\u4ee5\u7ed9\u5927\u5bb6\u6f14\u793a\u51fa\u7d22\u5f15\u4e0b\u63a8\u7684\u7279\u70b9\uff08\u4e0d\u61c2 docker \u7684\u5c0f\u4f19\u4f34\u53ef\u4ee5\u5728\u516c\u4f17\u53f7\u540e\u53f0\u56de\u590d docker\uff0c\u6709\u677e\u54e5\u5199\u7684\u5165\u95e8\u6559\u7a0b\uff09\u3002<\/p>\n

1.1 \u51c6\u5907\u5de5\u4f5c<\/h3>\n

\u9996\u5148\u6211\u6709\u5982\u4e0b\u4e00\u5f20\u8868\uff1a<\/p>\n

CREATE TABLE `user2` (\n  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,\n  `username` varchar(255) COLLATE utf8mb4_unicode_ci DEFAULT NULL,\n  `age` int(11) DEFAULT NULL,\n  `address` varchar(255) COLLATE utf8mb4_unicode_ci DEFAULT NULL,\n  PRIMARY KEY (`id`),\n  KEY `username` (`username`(191),`age`)\n) ENGINE=InnoDB AUTO_INCREMENT=100001 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;<\/code><\/pre>\n
\u6211\u5728 MySQL5.5 \u548c MySQL5.7 \u4e2d\u5206\u522b\u6267\u884c\u5982\u4e0a SQL\uff0c\u786e\u4fdd\u4e24\u4e2a MySQL \u4e2d\u90fd\u6709\u8fd9\u6837\u4e00\u5f20\u8868\u3002\u8fd9\u5f20\u8868\u4e2d\u6709\u4e00\u4e2a\u7531 username \u548c age \u7ec4\u6210\u7684\u590d\u5408\u7d22\u5f15\uff0c\u7d22\u5f15\u540d\u5b57\u5c31\u53eb username\uff0c\u5728\u672c\u6587\u63a5\u4e0b\u6765\u7684\u5185\u5bb9\u4e2d\uff0c\u6211\u8bf4 username \u7d22\u5f15\u5c31\u662f\u6307\u8be5\u590d\u5408\u7d22\u5f15\u3002<\/p>\n
\u8868\u521b\u5efa\u6210\u529f\u540e\uff0c\u5404\u81ea\u6dfb\u52a0\u4e00\u4e9b\u6a21\u62df\u6570\u636e\uff0c\u8fd9\u4e2a\u6211\u5c31\u4e0d\u6f14\u793a\u4e86\uff0c\u901a\u8fc7\u5b58\u50a8\u8fc7\u7a0b\u6216\u8005 Java \u4ee3\u7801\u90fd\u80fd\u6dfb\u52a0\u6a21\u62df\u6570\u636e\uff0c\u8fd9\u4e2a\u5c0f\u4f19\u4f34\u4eec\u81ea\u884c\u89e3\u51b3\u5373\u53ef\u3002<\/p>\n
OK\uff0c\u8fd9\u6837\u6211\u4eec\u7684\u51c6\u5907\u5de5\u4f5c\u5c31\u7b97\u5b8c\u6210\u4e86\u3002<\/p>\n
1.2 MySQL 5.5<\/h3>\n
\u5148\u6765\u7ed9\u5c0f\u4f19\u4f34\u4eec\u6f14\u793a\u4e00\u4e2a MySQL5.5 \u4e2d\u7684\u67e5\u8be2\u6848\u4f8b\u3002<\/p>\n
\u4e3a\u4e86\u65b9\u4fbf\u540e\u6587\u7684\u8868\u8ff0\uff0c\u6211\u7ed9\u6bcf\u4e00\u6761 SQL \u90fd\u53d6\u4e00\u4e2a\u6807\u8bb0\uff1a<\/p>\n
\u6765\u770b\u5982\u4e0b SQL\uff08SQL1\uff09\uff1a<\/p>\n
select * from user2 where username='1' and age=99;<\/code><\/pre>\n
\u6839\u636e username \u548c age \u67e5\u8be2\u4e00\u6761\u8bb0\u5f55\uff0c\u6211\u4eec\u6765\u770b\u770b\u8fd9\u6761 SQL \u7684\u6267\u884c\u8ba1\u5212\uff08\u4e3a\u4e86\u5c0f\u4f19\u4f34\u4eec\u9605\u8bfb\u65b9\u4fbf\uff0c\u6211\u52a0\u4e86 \/G<\/code> \u628a\u6570\u636e\u7528\u5217\u7684\u5f62\u5f0f\u5c55\u793a\uff09\uff1a<\/p>\n
\"\"<\/p>\n
\u5927\u81f4\u7785\u4e00\u773c\uff0c\u6211\u4eec\u53d1\u73b0\u8fd9\u4e2a\u662f\u7528\u4e86\u7d22\u5f15\u7684\uff0c\u4f46\u662f\u5177\u4f53\u662f\u600e\u4e48\u7528\u7684\uff0c\u6211\u6765\u548c\u5927\u5bb6\u8bf4\u9053\u8bf4\u9053\uff01<\/p>\n
\u5728 MySQL5.5 \u4e2d\uff0c\u7531\u4e8e\u6ca1\u6709\u7d22\u5f15\u4e0b\u63a8\uff0c\u6240\u4ee5\u4e0a\u9762\u8fd9\u4e2a SQL \u7684\u6267\u884c\u6d41\u7a0b\u662f\u8fd9\u6837\u7684\uff1a<\/p>\n
    \n
  1. \u9996\u5148 MySQL \u7684 server \u5c42\u8c03\u7528\u5b58\u50a8\u5f15\u64ce\u83b7\u53d6 username=’1′ \u7684\u7b2c\u4e00\u6761\u8bb0\u5f55\u3002<\/li>\n
  2. \u5b58\u50a8\u5f15\u64ce\u627e\u5230 username=’1′ \u7684\u7b2c\u4e00\u6761\u8bb0\u5f55\u540e\uff0c\u5728 B+Tree \u7684\u53f6\u5b50\u7ed3\u70b9\u4e2d\u4fdd\u5b58\u7740\u4e3b\u952e id\uff0c\u6b64\u65f6\u901a\u8fc7\u56de\u8868\u64cd\u4f5c\uff0c\u53bb\u4e3b\u952e\u7d22\u5f15\u4e2d\u627e\u5230\u8be5\u6761\u8bb0\u5f55\u7684\u5b8c\u6574\u6570\u636e\uff0c\u5e76\u8fd4\u56de\u7ed9 server \u5c42\u3002<\/li>\n
  3. server \u5c42\u62ff\u5230\u6570\u636e\u4e4b\u540e\uff0c\u5224\u65ad\u8be5\u6761\u8bb0\u5f55\u7684 age \u662f\u5426\u4e3a 99\uff0c\u5982\u679c age=99\uff0c\u5c31\u628a\u8be5\u6761\u8bb0\u5f55\u8fd4\u56de\u7ed9\u5ba2\u6237\u7aef\uff0c\u5982\u679c age!=99\uff0c\u90a3\u5c31\u5c31\u4e22\u5f03\u8be5\u8bb0\u5f55\u3002<\/li>\n
  4. \u7531\u4e8e username+age \u7ec4\u6210\u7684\u590d\u5408\u7d22\u5f15\u53ea\u662f\u4e00\u4e2a\u666e\u901a\u7d22\u5f15\uff0c\u5e76\u4e0d\u662f\u552f\u4e00\u7d22\u5f15\uff08\u5982\u679c\u662f\u552f\u4e00\u7d22\u5f15\uff0c\u90a3\u4e48\u8fd9\u4e2a\u67e5\u8be2\u5c31\u5230\u6b64\u7ed3\u675f\u4e86\uff09\uff0c\u6240\u4ee5\u8fd8\u9700\u8981\u7ee7\u7eed\u53bb\u641c\u7d22\u6709\u6ca1\u6709\u6ee1\u8db3\u6761\u4ef6\u7684\u8bb0\u5f55\u3002<\/li>\n<\/ol>\n
    \u4f46\u662f\u6ce8\u610f\u7b2c\u56db\u6b65\u7684\u641c\u7d22\u65b9\u5f0f\uff0c\u4e0d\u662f\u76f4\u63a5\u53bb B+Tree \u4e2d\u641c\u7d22\u4e86\u3002\u7531\u4e8e\u5728 username \u7d22\u5f15\u4e2d\uff0cusername \u5b57\u6bb5\u7684\u5b58\u50a8\u662f\u6709\u5e8f\u7684\uff0c\u5373 username=’1′ \u7684\u8bb0\u5f55\u90fd\u662f\u6328\u7740\u7684\uff0c\u800c B+Tree \u7684\u53f6\u5b50\u7ed3\u70b9\u4e4b\u95f4\u901a\u8fc7\u53cc\u5411\u94fe\u8868\u5173\u8054\uff0c\u901a\u8fc7\u4e00\u4e2a\u53f6\u5b50\u7ed3\u70b9\u5c31\u80fd\u627e\u5230\u4e0b\u4e00\u4e2a\u53f6\u5b50\u7ed3\u70b9\uff08\u6216\u8005\u4e0a\u4e00\u4e2a\u53f6\u5b50\u7ed3\u70b9\uff09\uff0c\u7b2c\u4e8c\u6b65\u8fd4\u56de\u7684\u6570\u636e\u4e2d\u6709\u4e00\u4e2a next_record \u5c5e\u6027\uff0c\u8be5\u5c5e\u6027\u5c31\u76f4\u63a5\u6307\u5411\u4e8c\u7ea7\u7d22\u5f15\u7684\u4e0b\u4e00\u6761\u8bb0\u5f55\uff0c\u627e\u5230\u4e0b\u4e00\u6761\u8bb0\u5f55\u540e\uff0c\u56de\u8868\u62ff\u5230\u6240\u6709\u6570\u636e\u5e76\u8fd4\u56de\u7ed9 server \u5c42\uff0c\u7136\u540e\u91cd\u590d 3\u30014 \u6b65\u3002<\/strong><\/p>\n
    \u6211\u4eec\u770b\u770b\u4e0a\u9762\u7684\u6267\u884c\u8ba1\u5212\uff0c\u548c\u6211\u4eec\u7684\u5206\u6790\u662f\u4e00\u81f4\u7684\uff1a<\/p>\n