{"id":2432,"date":"2015-08-02T17:03:17","date_gmt":"2015-08-02T09:03:17","guid":{"rendered":"http:\/\/ixyzero.com\/blog\/?p=2432"},"modified":"2015-08-02T17:03:17","modified_gmt":"2015-08-02T09:03:17","slug":"collectmysql%e7%9a%84%e5%bc%80%e5%8f%91%e8%a7%84%e8%8c%83","status":"publish","type":"post","link":"https:\/\/ixyzero.com\/blog\/archives\/2432.html","title":{"rendered":"[collect]MySQL\u7684\u5f00\u53d1\u89c4\u8303"},"content":{"rendered":"
\u539f\u6587\u94fe\u63a5\uff1a<\/h6>\n

\u8001\u53f6\u89c2\u70b9\uff1aMySQL\u5f00\u53d1\u89c4\u8303\u4e4b\u6211\u89c1<\/a><\/p>\n

\n

\u5927\u591a\u6570MySQL\u89c4\u8303\u5728\u7f51\u4e0a\u4e5f\u90fd\u80fd\u627e\u5f97\u5230\u76f8\u5173\u7684\u5206\u4eab\uff0c\u5728\u8fd9\u91cc\u8981\u5206\u4eab\u7684\u662f\u8001\u53f6\u4e2a\u4eba\u8ba4\u4e3a\u6bd4\u8f83\u91cd\u8981\u7684\uff0c\u6216\u8005\u5bb9\u6613\u88ab\u5ffd\u89c6\u7684\uff0c\u4ee5\u53ca\u5bb9\u6613\u88ab\u6df7\u6dc6\u7684\u4e00\u4e9b\u5730\u65b9\u3002<\/p>\n

1\u3001\u9ed8\u8ba4\u4f7f\u7528InnoDB\u5f15\u64ce<\/h5>\n

\u3010\u8001\u53f6\u89c2\u70b9\u3011\u5df2\u591a\u6b21\u547c\u5401\u8fc7\u4e86\uff0cInnoDB\u9002\u7528\u4e8e\u51e0\u4e4e99%\u7684MySQL\u5e94\u7528\u573a\u666f<\/span><\/strong>\uff0c\u800c\u4e14\u5728MySQL 5.7\u7684\u7cfb\u7edf\u8868\u90fd\u6539\u6210InnoDB\u4e86\uff0c\u8fd8\u6709\u4ec0\u4e48\u7406\u7531\u518d\u6b7b\u5b88MyISAM\u5462\u3002<\/p>\n

\u6b64\u5916\uff0c\u9891\u7e41\u8bfb\u5199\u7684InnoDB\u8868\uff0c\u4e00\u5b9a\u8981\u4f7f\u7528\u5177\u6709\u81ea\u589e\/\u987a\u5e8f\u7279\u5f81\u7684\u6574\u578b\u4f5c\u4e3a\u663e\u5f0f\u4e3b\u952e\u3002<\/p>\n

\u3010\u53c2\u8003\u3011\uff1a[MySQL FAQ]\u7cfb\u5217 \u2014 \u4e3a\u4ec0\u4e48InnoDB\u8868\u8981\u5efa\u8bae\u7528\u81ea\u589e\u5217\u505a\u4e3b\u952e<\/a>\u3002<\/p>\n

2\u3001\u5b57\u7b26\u96c6\u9009\u62e9utf-8<\/h5>\n

\u3010\u8001\u53f6\u89c2\u70b9\u3011\u82e5\u4e3a\u4e86\u8282\u7701\u78c1\u76d8\u7a7a\u95f4\uff0c\u5219\u5efa\u8bae\u9009\u62e9latin1\u3002\u5efa\u8bae\u9009\u62e9utf-8\u901a\u5e38\u662f\u4e3a\u4e86\u6240\u8c13\u7684\u201c\u901a\u7528\u6027\u201d\uff0c\u4f46\u4e8b\u5b9e\u4e0a\u7528\u6237\u63d0\u4ea4\u7684utf-8\u6570\u636e\u4e5f\u4e00\u6837\u53ef\u4ee5\u4ee5latin1\u5b57\u7b26\u96c6\u5b58\u50a8\u3002<\/p>\n

\u7528latin1\u5b58\u50a8utf-8\u6570\u636e\u53ef\u80fd\u9047\u5230\u7684\u9ebb\u70e6\u662f\uff0c\u5982\u679c\u6709\u57fa\u4e8e\u4e2d\u6587\u7684\u68c0\u7d22\u65f6\uff0c\u53ef\u80fd\u65e0\u6cd5100%\u51c6\u786e\uff08\u8001\u53f6\u4eb2\u81ea\u7b80\u5355\u6d4b\u8bd5\u5e38\u89c4\u7684\u4e2d\u6587\u5b8c\u68c0\u7d22\u5168\u4e0d\u662f\u95ee\u9898\uff0c\u4e5f\u5c31\u662f\u4e00\u822c\u7684\u4e2d\u6587\u5bf9\u6bd4\u662f\u6ca1\u95ee\u9898\u7684\uff09\u3002<\/p>\n

\u7528latin1\u5b57\u7b26\u96c6\u5b58\u50a8utf-8\u6570\u636e\u7684\u505a\u6cd5\u662f\uff1a\u5728web\u7aef(\u7528\u6237\u7aef)\u7684\u5b57\u7b26\u96c6\u662futf-8\uff0c\u540e\u7aef\u7a0b\u5e8f\u4e5f\u91c7\u7528utf-8\u6765\u5904\u7406\uff0c\u4f46\u00a0character_set_client\u3001character_set_connection\u3001character_set_results\u3001character_set_database\u3001character_set_server \u8fd9\u51e0\u4e2a\u90fd\u662f latin1\uff0c\u4e14\u6570\u636e\u8868\u3001\u5b57\u6bb5\u7684\u5b57\u7b26\u96c6\u4e5f\u662flatin1\u3002\u6216\u8005\u8bf4\u6570\u636e\u8868\u91c7\u7528latin1\uff0c\u6bcf\u6b21\u8fde\u63a5\u540e\u6267\u884c\u00a0SET NAMES LATIN1\u00a0\u5373\u53ef\u3002<\/p>\n

\u3010\u53c2\u8003\u3011\uff1a\u5c0f\u8c08MySQL\u5b57\u7b26\u96c6<\/a>\u3002<\/p>\n

3\u3001InnoDB\u8868\u884c\u8bb0\u5f55\u7269\u7406\u957f\u5ea6\u4e0d\u8d85\u8fc78KB<\/h5>\n

\u3010\u8001\u53f6\u89c2\u70b9\u3011InnoDB\u7684data page\u9ed8\u8ba4\u662f16KB\uff0c\u57fa\u4e8eB+Tree\u7684\u7279\u70b9\uff0c\u4e00\u4e2adata page\u4e2d\u9700\u8981\u81f3\u5c11\u5b58\u50a82\u6761\u8bb0\u5f55\u3002\u56e0\u6b64\uff0c\u5f53\u5b9e\u9645\u5b58\u50a8\u957f\u5ea6\u8d85\u8fc78KB\uff08\u5c24\u5176\u662fTEXT\/BLOB\u5217\uff09\u7684\u5927\u5217\uff08large column\uff09\u65f6\u4f1a\u5f15\u8d77\u201cpage-overflow\u5b58\u50a8\u201d\uff0c\u7c7b\u4f3cORACLE\u4e2d\u7684\u201c\u884c\u8fc1\u79fb\u201d\u3002<\/p>\n

\u56e0\u6b64\uff0c\u5982\u679c\u5fc5\u987b\u4f7f\u7528\u5927\u5217\uff08\u5c24\u5176\u662fTEXT\/BLOB\u7c7b\u578b\uff09\u4e14\u8bfb\u5199\u9891\u7e41\u7684\u8bdd\uff0c\u5219\u6700\u597d\u628a\u8fd9\u4e9b\u5217\u62c6\u5206\u5230\u5b50\u8868\u4e2d\uff0c\u4e0d\u8981\u548c\u4e3b\u8868\u653e\u5728\u4e00\u8d77\u5b58\u50a8\u3002\u5982\u679c\u4e0d\u592a\u9891\u7e41\uff0c\u53ef\u4ee5\u8003\u8651\u7ee7\u7eed\u4fdd\u7559\u5728\u4e3b\u8868\u4e2d\u3002<\/p>\n

\u5f53\u7136\u4e86\uff0c\u5982\u679c\u5c06\u00a0innodb_page_size \u9009\u9879\u4fee\u6539\u6210 8KB\uff0c\u90a3\u4e48\u884c\u8bb0\u5f55\u7269\u7406\u957f\u5ea6\u5efa\u8bae\u4e0d\u8d85\u8fc74KB\u3002<\/p>\n

\u3010\u53c2\u8003\u3011\uff1a[MySQL\u4f18\u5316\u6848\u4f8b]\u7cfb\u5217 \u2014 \u4f18\u5316InnoDB\u8868BLOB\u5217\u7684\u5b58\u50a8\u6548\u7387<\/a>\u3002<\/p>\n

4\u3001\u662f\u5426\u4f7f\u7528\u5206\u533a\u8868<\/h5>\n

\u3010\u8001\u53f6\u89c2\u70b9\u3011\u5728\u4e00\u4e9b\u4f7f\u7528\u5206\u533a\u8868\u540e\u660e\u663e\u53ef\u4ee5\u63d0\u5347\u6027\u80fd\u6216\u8005\u8fd0\u7ef4\u4fbf\u5229\u6027\u7684\u573a\u666f\u4e0b\uff0c\u8fd8\u662f\u5efa\u8bae\u4f7f\u7528\u5206\u533a\u8868\u3002<\/p>\n

\u6bd4\u5982\u8001\u53f6\u5c31\u5728zabbix\u7684\u6570\u636e\u5e93\u91c7\u7528TokuDB\u5f15\u64ce\u7684\u524d\u63d0\u4e0b\uff0c\u53c8\u6839\u636e\u65f6\u95f4\u7ef4\u5ea6\u4f7f\u7528\u4e86\u5206\u533a\u8868\u3002\u8fd9\u6837\u7684\u597d\u5904\u662f\u4fdd\u8bc1zabbix\u65e5\u5e38\u5e94\u7528\u4e0d\u53d7\u5230\u5f71\u54cd\u524d\u63d0\u4e0b\uff0c\u65b9\u4fbf\u7ba1\u7406\u5458\u4f8b\u884c\u5220\u9664\u8fc7\u53bb\u6570\u636e\uff0c\u53ea\u9700\u8981\u5220\u9664\u76f8\u5e94\u5206\u533a\u5373\u53ef\uff0c\u4e0d\u9700\u518d\u6267\u884c\u4e00\u4e2a\u975e\u5e38\u6162\u7684DELETE\u800c\u5f71\u54cd\u6574\u4f53\u6027\u80fd\u3002<\/p>\n

\u3010\u53c2\u8003\u3011\uff1a\u8fc1\u79fbZabbix\u6570\u636e\u5e93\u5230TokuDB<\/a>\u3002<\/p>\n

5\u3001\u662f\u5426\u4f7f\u7528\u5b58\u50a8\u8fc7\u7a0b\u3001\u89e6\u53d1\u5668<\/h5>\n

\u3010\u8001\u53f6\u89c2\u70b9\u3011\u5728\u4e00\u4e9b\u5408\u9002\u7684\u573a\u666f\u4e0b\uff0c\u7528\u5b58\u50a8\u8fc7\u7a0b\u3001\u89e6\u53d1\u5668\u4e5f\u5b8c\u5168\u6ca1\u95ee\u9898\u3002<\/p>\n

\u6211\u4eec\u4ee5\u524d\u5c31\u662f\u5229\u7528\u5b58\u50a8\u5b8c\u6210\u6e38\u620f\u4e1a\u52a1\u903b\u8f91\u5904\u7406\uff0c\u6027\u80fd\u4e0a\u4e0d\u662f\u95ee\u9898\uff0c\u800c\u4e14\u4e00\u65e6\u9700\u6c42\u6709\u53d8\u66f4\uff0c\u53ea\u9700\u4fee\u6539\u5b58\u50a8\u8fc7\u7a0b\uff0c\u53d8\u66f4\u4ee3\u4ef7\u5f88\u4f4e\u3002\u6211\u4eec\u8fd8\u5229\u7528\u89e6\u53d1\u5668\u7ef4\u62a4\u4e00\u4e2a\u9891\u7e41\u66f4\u65b0\u7684\u8868\uff0c\u5bf9\u8fd9\u4e2a\u8868\u7684\u6240\u6709\u53d8\u66f4\u90fd\u5c06\u90e8\u5206\u5b57\u6bb5\u540c\u6b65\u66f4\u65b0\u5230\u53e6\u4e00\u4e2a\u8868\u4e2d\uff08\u7c7b\u4f3c\u7269\u5316\u89c6\u56fe\u7684\u53d8\u76f8\u5b9e\u73b0\uff09\uff0c\u4e5f\u4e0d\u5b58\u5728\u6027\u80fd\u95ee\u9898\u3002<\/p>\n

\u4e0d\u8981\u628aMySQL\u7684\u5b58\u50a8\u8fc7\u7a0b\u548c\u89e6\u53d1\u5668\u89c6\u4e3a\u6d2a\u6c34\u731b\u517d\uff0c\u7528\u597d\u7684\u8bdd\uff0c\u6ca1\u6709\u95ee\u9898\u7684\uff0c\u771f\u9047\u5230\u95ee\u9898\u4e86\u518d\u4f18\u5316\u4e5f\u4e0d\u8fdf\u3002\u53e6\u5916\uff0cMySQL\u56e0\u4e3a\u6ca1\u6709\u7269\u5316\u89c6\u56fe\uff0c\u56e0\u6b64\u89c6\u56fe\u80fd\u4e0d\u7528\u5c31\u5c3d\u91cf\u5c11\u7528\u5427\u3002<\/p>\n

6\u3001\u9009\u62e9\u5408\u9002\u7684\u7c7b\u578b<\/h5>\n

\u3010\u8001\u53f6\u89c2\u70b9\u3011\u9664\u4e86\u5e38\u89c1\u7684\u5efa\u8bae\u5916\uff0c\u8fd8\u6709\u5176\u4ed6\u51e0\u4e2a\u8981\u70b9\uff1a<\/p>\n

6.1\u3001\u7528INT UNSIGNED\u5b58\u50a8IPV4\u5730\u5740\uff0c\u7528INET_ATON()\u3001INET_NTOA()\u8fdb\u884c\u8f6c\u6362\uff0c\u57fa\u672c\u4e0a\u6ca1\u5fc5\u8981\u4f7f\u7528CHAR(15)\u6765\u5b58\u50a8\u3002<\/p>\n

6.2\u3001\u679a\u4e3e\u7c7b\u578b\u53ef\u4ee5\u4f7f\u7528ENUM\uff0cENUM\u7684\u5185\u90e8\u5b58\u50a8\u673a\u5236\u662f\u91c7\u7528TINYINT\u6216SMALLINT\uff08\u5e76\u975eCHAR\/VARCHAR\uff09\uff0c\u6027\u80fd\u4e00\u70b9\u90fd\u4e0d\u5dee\uff0c\u8bb0\u4f4f\u5343\u4e07\u522b\u7528CHAR\/VARCHAR \u6765\u5b58\u50a8\u679a\u4e3e\u6570\u636e\u3002<\/p>\n

6.3\u3001\u8fd8\u4e2a\u65e9\u524d\u4e00\u76f4\u5728\u4f20\u64ad\u7684\u201c\u5e38\u8bc6\u6027\u8bef\u5bfc\u201d\uff0c\u5efa\u8bae\u7528TIMESTAMP\u53d6\u4ee3DATETIME\u3002\u5176\u5b9e\u4ece5.6\u5f00\u59cb\uff0c\u5efa\u8bae\u4f18\u5148\u9009\u62e9DATETIME\u5b58\u50a8\u65e5\u671f\u65f6\u95f4\uff0c\u56e0\u4e3a\u5b83\u7684\u53ef\u7528\u8303\u56f4\u6bd4TIMESTAMP\u66f4\u5927\uff0c\u7269\u7406\u5b58\u50a8\u4e0a\u4ec5\u6bd4TIMESTAMP\u591a1\u4e2a\u5b57\u8282\uff0c\u6574\u4f53\u6027\u80fd\u4e0a\u7684\u635f\u5931\u5e76\u4e0d\u5927\u3002<\/p>\n

6.4\u3001\u6240\u6709\u5b57\u6bb5\u5b9a\u4e49\u4e2d\uff0c\u9ed8\u8ba4\u90fd\u52a0\u4e0aNOT NULL\u7ea6\u675f\uff0c\u9664\u975e\u5fc5\u987b\u4e3aNULL\uff08\u4f46\u6211\u4e5f\u60f3\u4e0d\u51fa\u6765\u4ec0\u4e48\u573a\u666f\u4e0b\u5fc5\u987b\u8981\u5728\u6570\u636e\u5e93\u4e2d\u5b58\u50a8NULL\u503c\uff0c\u53ef\u4ee5\u75280\u6765\u8868\u793a\uff09\u3002\u5728\u5bf9\u8be5\u5b57\u6bb5\u8fdb\u884cCOUNT()\u7edf\u8ba1\u65f6\uff0c\u7edf\u8ba1\u7ed3\u679c\u66f4\u51c6\u786e\uff08\u503c\u4e3aNULL\u7684\u4e0d\u4f1a\u88abCOUNT\u7edf\u8ba1\u8fdb\u53bb\uff09\uff0c\u6216\u8005\u6267\u884c WHERE column IS NULL \u68c0\u7d22\u65f6\uff0c\u4e5f\u53ef\u4ee5\u5feb\u901f\u8fd4\u56de\u7ed3\u679c\u3002<\/p>\n

6.5\u3001\u5c3d\u53ef\u80fd\u4e0d\u8981\u76f4\u63a5 SELECT * \u8bfb\u53d6\u5168\u90e8\u5b57\u6bb5\uff0c\u5c24\u5176\u662f\u8868\u4e2d\u5b58\u5728 TEXT\/BLOB \u5927\u5217\u7684\u65f6\u5019\u3002\u53ef\u80fd\u672c\u6765\u4e0d\u9700\u8981\u8bfb\u53d6\u8fd9\u4e9b\u5217\uff0c\u4f46\u56e0\u4e3a\u5077\u61d2\u5199\u6210 SELECT * \u5bfc\u81f4\u5185\u5b58buffer pool\u88ab\u8fd9\u4e9b\u201c\u5783\u573e\u201d\u6570\u636e\u628a\u771f\u6b63\u9700\u8981\u7f13\u51b2\u8d77\u6765\u7684\u70ed\u70b9\u6570\u636e\u7ed9\u6d17\u51fa\u53bb\u4e86\u3002<\/p>\n

7\u3001\u5173\u4e8e\u7d22\u5f15<\/h5>\n

\u3010\u8001\u53f6\u89c2\u70b9\u3011\u9664\u4e86\u5e38\u89c1\u7684\u5efa\u8bae\u5916\uff0c\u8fd8\u6709\u51e0\u4e2a\u8981\u70b9\uff1a<\/p>\n

7.1\u3001\u8d85\u8fc720\u4e2a\u957f\u5ea6\u7684\u5b57\u7b26\u4e32\u5217\uff0c\u6700\u597d\u521b\u5efa\u524d\u7f00\u7d22\u5f15\u800c\u975e\u6574\u5217\u7d22\u5f15\uff08\u4f8b\u5982\uff1aALTER TABLE t1 ADD INDEX(user(20))\uff09\uff0c\u53ef\u4ee5\u6709\u6548\u63d0\u9ad8\u7d22\u5f15\u5229\u7528\u7387\uff0c\u4e0d\u8fc7\u5b83\u7684\u7f3a\u70b9\u662f\u5bf9\u8fd9\u4e2a\u5217\u6392\u5e8f\u65f6\u7528\u4e0d\u5230\u524d\u7f00\u7d22\u5f15\u3002\u524d\u7f00\u7d22\u5f15\u7684\u957f\u5ea6\u53ef\u4ee5\u57fa\u4e8e\u5bf9\u8be5\u5b57\u6bb5\u7684\u7edf\u8ba1\u5f97\u51fa\uff0c\u4e00\u822c\u7565\u5927\u4e8e\u5e73\u5747\u957f\u5ea6\u4e00\u70b9\u5c31\u53ef\u4ee5\u4e86\u3002<\/p>\n

7.2\u3001\u5b9a\u671f\u7528 pt-duplicate-key-checker \u5de5\u5177\u68c0\u67e5\u5e76\u5220\u9664\u91cd\u590d\u7684\u7d22\u5f15\u3002\u6bd4\u5982 index idx1(a, b) \u7d22\u5f15\u5df2\u7ecf\u6db5\u76d6\u4e86 index idx2(a)\uff0c\u5c31\u53ef\u4ee5\u5220\u9664 idx2 \u7d22\u5f15\u4e86\u3002<\/p>\n

7.3\u3001\u6709\u591a\u5b57\u6bb5\u8054\u5408\u7d22\u5f15\u65f6\uff0cwhere\u4e2d\u8fc7\u6ee4\u6761\u4ef6\u7684\u5b57\u6bb5\u987a\u5e8f\u65e0\u9700\u548c\u7d22\u5f15\u4e00\u81f4\uff0c\u4f46\u5982\u679c\u6709\u6392\u5e8f\u3001\u5206\u7ec4\u5219\u5c31\u5fc5\u987b\u4e00\u81f4\u4e86<\/span><\/strong>\u3002<\/p>\n

\u6bd4\u5982\u6709\u8054\u5408\u7d22\u5f15 idx1(a, b, c)\uff0c\u90a3\u4e48\u4e0b\u9762\u7684SQL\u90fd\u53ef\u4ee5\u5b8c\u6574\u7528\u5230\u7d22\u5f15\uff1a<\/p>\n

SELECT ... WHERE b = ? AND c = ? AND a = ?; --\u6ce8\u610f\u5230\uff0cWHERE\u4e2d\u5b57\u6bb5\u987a\u5e8f\u5e76\u6ca1\u6709\u548c\u7d22\u5f15\u5b57\u6bb5\u987a\u5e8f\u4e00\u81f4\nSELECT ... WHERE b = ? AND a = ? AND c = ?;\nSELECT ... WHERE a = ? AND b IN (?, ?) AND c = ?;\nSELECT ... WHERE a = ? AND b = ? ORDER BY c;\nSELECT ... WHERE a = ? AND b IN (?, ?) ORDER BY c;\nSELECT ... WHERE a = ? ORDER BY b, c;\nSELECT ... ORDER BY a, b, c;    -- \u53ef\u5229\u7528\u8054\u5408\u7d22\u5f15\u5b8c\u6210\u6392\u5e8f<\/pre>\n
\u800c\u4e0b\u9762\u51e0\u4e2aSQL\u5219\u53ea\u80fd\u7528\u5230\u90e8\u5206\u7d22\u5f15\uff0c\u6216\u8005\u53ef\u5229\u7528\u5230ICP\u7279\u6027\uff1a<\/p>\n
SELECT ... WHERE b = ? AND a = ?;       -- \u53ea\u80fd\u7528\u5230 (a, b) \u90e8\u5206\nSELECT ... WHERE a IN (?, ?) AND b = ?; -- EXPLAIN\u663e\u793a\u53ea\u7528\u5230 (a, b) \u90e8\u5206\u7d22\u5f15\uff0c\u540c\u65f6\u6709ICP\nSELECT ... WHERE (a BETWEEN ? AND ?) AND b = ?; -- EXPLAIN\u663e\u793a\u53ea\u7528\u5230 (a, b) \u90e8\u5206\u7d22\u5f15\uff0c\u540c\u65f6\u6709ICP\nSELECT ... WHERE a = ? AND b IN (?, ?);         -- EXPLAIN\u663e\u793a\u53ea\u7528\u5230 (a, b) \u90e8\u5206\u7d22\u5f15\uff0c\u540c\u65f6\u6709ICP\nSELECT ... WHERE a = ? AND (b BETWEEN ? AND ?) AND c = ?;   -- EXPLAIN\u663e\u793a\u7528\u5230 (a, b, c) \u6574\u4e2a\u7d22\u5f15\uff0c\u540c\u65f6\u6709ICP\nSELECT ... WHERE a = ? AND c = ?;   -- EXPLAIN\u663e\u793a\u53ea\u7528\u5230 (a) \u90e8\u5206\u7d22\u5f15\uff0c\u540c\u65f6\u6709ICP\nSELECT ... WHERE a = ? AND c >= ?;  -- EXPLAIN\u663e\u793a\u53ea\u7528\u5230 (a) \u90e8\u5206\u7d22\u5f15\uff0c\u540c\u65f6\u6709ICP<\/pre>\n
ICP\uff08index condition pushdown\uff09\u662fMySQL 5.6\u7684\u65b0\u7279\u6027\uff0c\u5176\u673a\u5236\u4f1a\u8ba9\u7d22\u5f15\u7684\u5176\u4ed6\u90e8\u5206\u4e5f\u53c2\u4e0e\u8fc7\u6ee4\uff0c\u51cf\u5c11\u5f15\u64ce\u5c42\u548cserver\u5c42\u4e4b\u95f4\u7684\u6570\u636e\u4f20\u8f93\u548c\u56de\u8868\u8bf7\u6c42\uff0c\u901a\u5e38\u60c5\u51b5\u4e0b\u53ef\u5927\u5e45\u63d0\u5347\u67e5\u8be2\u6548\u7387\u3002<\/p>\n
\u4e0b\u9762\u7684\u51e0\u4e2aSQL\u5b8c\u5168\u7528\u4e0d\u5230\u8be5\u7d22\u5f15\uff1a<\/p>\n
SELECT ... WHERE b\u00a0= ?;\nSELECT ... WHERE b\u00a0= ?\u00a0AND c = ?;\nSELECT ... WHERE b\u00a0= ?\u00a0AND c = ?;\nSELECT ... ORDER\u00a0BY b;\nSELECT ... ORDER\u00a0BY b, a;<\/pre>\n
\u4ece\u4e0a\u9762\u7684\u51e0\u4e2a\u4f8b\u5b50\u5c31\u80fd\u770b\u7684\u51fa\u6765\uff0c\u4ee5\u5f80\u5f3a\u8c03\u7684where\u6761\u4ef6\u5b57\u6bb5\u987a\u5e8f\u8981\u548c\u7d22\u5f15\u987a\u5e8f\u4e00\u81f4\u624d\u80fd\u4f7f\u7528\u7d22\u5f15\u7684\u201c\u5e38\u8bc6\u6027\u8bef\u5bfc\u201d\u65e0\u9700\u4e25\u683c\u9075\u5b88<\/strong><\/span>\u3002<\/p>\n
\u6b64\u5916\uff0c\u6709\u4e9b\u65f6\u5019\u67e5\u8be2\u4f18\u5316\u5668\u6307\u5b9a\u7684\u7d22\u5f15\u6216\u6267\u884c\u8ba1\u5212\u53ef\u80fd\u5e76\u4e0d\u662f\u6700\u4f18\u7684\uff0c\u53ef\u4ee5\u624b\u5de5\u6307\u5b9a\u6700\u4f18\u7d22\u5f15\uff0c\u6216\u8005\u4fee\u6539session\u7ea7\u7684\u00a0optimizer_switch<\/a>\u00a0\u9009\u9879\uff0c\u5173\u95ed\u67d0\u4e9b\u5bfc\u81f4\u6548\u679c\u53cd\u800c\u66f4\u5dee\u7684\u7279\u6027\uff08\u6bd4\u5982index merge\u901a\u5e38\u662f\u597d\u4e8b\uff0c\u4f46\u4e5f\u9047\u5230\u8fc7\u7528\u4e0aindex merge\u540e\u53cd\u800c\u66f4\u5dee\u7684\uff0c\u8fd9\u65f6\u5019\u8981\u4e48\u5f3a\u5236\u6307\u5b9a\u5176\u4e2d\u4e00\u4e2a\u7d22\u5f15\uff0c\u8981\u4e48\u53ef\u4ee5\u4e34\u65f6\u5173\u95ed index merge \u7279\u6027\uff09\u3002<\/p>\n
8\u3001\u5176\u4ed6<\/h5>\n
8.1\u3001\u54ea\u6015\u662f\u57fa\u4e8e\u7d22\u5f15\u7684\u6761\u4ef6\u8fc7\u6ee4\uff0c\u5982\u679c\u4f18\u5316\u5668\u610f\u8bc6\u5230\u603b\u5171\u9700\u8981\u626b\u63cf\u7684\u6570\u636e\u91cf\u8d85\u8fc730%\u65f6\uff08ORACLE\u91cc\u8c8c\u4f3c\u662f20%\uff0cMySQL\u76ee\u524d\u662f30%\uff0c\u6ca1\u51c6\u4ee5\u540e\u4f1a\u8c03\u6574\uff09\uff0c\u5c31\u4f1a\u76f4\u63a5\u6539\u53d8\u6267\u884c\u8ba1\u5212\u4e3a\u5168\u8868\u626b\u63cf\uff0c\u4e0d\u518d\u4f7f\u7528\u7d22\u5f15\u3002<\/p>\n
8.2\u3001\u591a\u8868JOIN\u65f6\uff0c\u8981\u628a\u8fc7\u6ee4\u6027\u6700\u5927\uff08\u4e0d\u4e00\u5b9a\u662f\u6570\u636e\u91cf\u6700\u5c0f\u54e6\uff0c\u800c\u662f\u53ea\u52a0\u4e86WHERE\u6761\u4ef6\u540e\u8fc7\u6ee4\u6027\u6700\u5927\u7684\u90a3\u4e2a\uff09\u7684\u8868\u9009\u4e3a\u9a71\u52a8\u8868\u3002\u6b64\u5916\uff0c\u5982\u679cJOIN\u4e4b\u540e\u6709\u6392\u5e8f\uff0c\u6392\u5e8f\u5b57\u6bb5\u4e00\u5b9a\u8981\u5c5e\u4e8e\u9a71\u52a8\u8868\uff0c\u624d\u80fd\u5229\u7528\u9a71\u52a8\u8868\u4e0a\u7684\u7d22\u5f15\u5b8c\u6210\u6392\u5e8f\u3002<\/p>\n
8.3\u3001\u7edd\u5927\u591a\u6570\u60c5\u51b5\u4e0b\uff0c\u6392\u5e8f\u7684\u4ee3\u4ef7\u901a\u5e38\u8981\u6765\u7684\u66f4\u9ad8\uff0c\u56e0\u6b64\u5982\u679c\u770b\u5230\u6267\u884c\u8ba1\u5212\u4e2d\u6709 Using filesort\uff0c\u4f18\u5148\u521b\u5efa\u6392\u5e8f\u7d22\u5f15\u5427\u3002<\/p>\n
8.4\u3001\u5229\u7528\u00a0pt-query-digest<\/a>\u00a0\u5b9a\u671f\u5206\u6790slow query log\uff0c\u5e76\u7ed3\u5408\u00a0Box Anemometer<\/a>\u00a0\u6784\u5efaslow query log\u5206\u6790\u53ca\u4f18\u5316\u7cfb\u7edf\u3002<\/p>\n
\u3010\u53c2\u8003\u3011\uff1a[MySQL FAQ]\u7cfb\u5217 \u2014 EXPLAIN\u7ed3\u679c\u4e2d\u54ea\u4e9b\u4fe1\u606f\u8981\u5f15\u8d77\u5173\u6ce8<\/a>\u3002<\/p>\n
\u5907\u6ce8\uff1a\u82e5\u65e0\u7279\u522b\u8bf4\u660e\uff0c\u4ee5\u4e0a\u89c4\u8303\u5efa\u8bae\u9002\u7528\u4e8eMySQL 5.6\u53ca\u4e4b\u524d\u7684\u7248\u672c\uff08\u5e76\u4e14\u4e3b\u8981\u662f5.6\u7248\u672c\uff0c\u5c24\u5176\u662fICP\u7279\u6027\u3001DATETIME\u53d8\u5316\u8fd9\u4e24\u4e2a\u5730\u65b9\uff09\u30025.7\u53ca\u4e4b\u540e\u7684\u7248\u672c\u53ef\u80fd\u4f1a\u6709\u4e9b\u53d8\u5316\uff0c\u4e2a\u522b\u89c4\u8303\u5efa\u8bae\u9700\u8981\u76f8\u5e94\u8c03\u6574\u3002<\/p>\n
\u66f4\u591a\u53c2\u8003\u94fe\u63a5\uff1a<\/h6>\n