{"id":10008306,"date":"2023-09-21T17:44:01","date_gmt":"2023-09-21T09:44:01","guid":{"rendered":"https:\/\/blog.itmax.cn\/?p=10008306"},"modified":"2023-09-21T17:44:01","modified_gmt":"2023-09-21T09:44:01","slug":"%e6%85%a2sql%e5%8e%9f%e5%9b%a0%e5%88%86%e6%9e%90%e4%b9%8b%e7%b4%a2%e5%bc%95%e5%a4%b1%e6%95%88-%e4%ba%ac%e4%b8%9c%e7%89%a9%e6%b5%81%e6%8a%80%e6%9c%af%e5%9b%a2%e9%98%9f","status":"publish","type":"post","link":"https:\/\/itmax.cn\/?p=10008306","title":{"rendered":"\u6162SQL\u539f\u56e0\u5206\u6790\u4e4b\u7d22\u5f15\u5931\u6548 | \u4eac\u4e1c\u7269\u6d41\u6280\u672f\u56e2\u961f"},"content":{"rendered":"<h2>\u73b0\u8c61<\/h2>\n<p>\u6700\u8fd1\u6536\u5230\u4e00\u4e2a\u6162sql\u5de5\u5355,\u6162sql\u5927\u6982\u662f\u8fd9\u6837\uff1a\u201cselect xxx from tabel where type = 1\u201d\u3002<\/p>\n<p>\u54a6\uff0ctype\u5b57\u6bb5\u660e\u660e\u6709\u7d22\u5f15\u554a\uff0c\u4e3a\u5565\u662f\u6162sql\u5462\uff1f<\/p>\n<h2>\u539f\u56e0<\/h2>\n<p>\u901a\u8fc7\u6267\u884cexplain\uff0c\u53d1\u73b0\u5b9e\u9645\u4e0a\u6570\u636e\u5e93\u6267\u884c\u4e86\u5168\u8868\u626b\u63cf\uff0c\u4ece\u800c\u88ab\u7cfb\u7edf\u5224\u5b9a\u4e3a\u6162sql\u3002\u8fd9\u65f6\u6709\u4e00\u5b9a\u5f00\u53d1\u7ecf\u9a8c\u7684\u540c\u4e8b\u4f1a\u8bf4\uff1a\u201c\u5b57\u6bb5\u533a\u5206\u5ea6\u4e0d\u591f\uff0c\u8fd9\u79cd\u5b57\u6bb5\u4f5c\u5355\u72ec\u7d22\u5f15\u662f\u6ca1\u6709\u610f\u4e49\u7684\u201d\u3002\u90a3\u4e48\u4e3a\u4ec0\u4e48\u4f1a\u4ea7\u751f\u7d22\u5f15\u5931\u6548\u8fd9\u79cd\u60c5\u51b5\u5462\uff1f\u7d22\u5f15\u5931\u6548\u90fd\u6709\u54ea\u4e9b\u60c5\u51b5\u5462\uff1f<\/p>\n<h2>\u7d22\u5f15\u5931\u6548\u6982\u62ec<\/h2>\n<p>\u4e0b\u9762\u603b\u7ed3\u4e86\u82e5\u5e72\u7d22\u5f15\u5931\u6548\u7684\u60c5\u51b5\uff1a<\/p>\n<h4>\u4e0d\u6ee1\u8db3\u6700\u5de6\u5339\u914d<\/h4>\n<p>\u5047\u5982\u8868\u4e2d\u6709\u4e2a\u7ec4\u5408\u7d22\u5f15\uff0cidx\/_start\/_org\/_code\/_start\/_province\/_id\/_trans\/_type,\u5b83\u7684\u7d22\u5f15\u987a\u5e8f\u5982\u4e0b\uff1a<\/p>\n<p>start\/_org\/_code,<\/p>\n<p>start\/_province\/_id,<\/p>\n<p>trans_type<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044240485\" alt=\"\" title=\"\"><\/p>\n<p>\u5f53\u6211\u4eec\u4ece\u7b2c\u4e8c\u4e2a\u7d22\u5f15\u5b57\u6bb5\u5f00\u59cb\u67e5\u8be2\u65f6\u5c31\u4e0d\u4f1a\u8d70\u7d22\u5f15\uff1a<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044240486\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>\u56e0\u4e3a\u7d22\u5f15\u662fBTree\u7ed3\u6784\u7684\uff0c\u4e0d\u80fd\u8df3\u8fc7\u7b2c\u4e00\u4e2a\u7d22\u5f15\u76f4\u63a5\u8d70\u7b2c\u4e8c\u4e2a\u7d22\u5f15<\/p>\n<h4>\u7d22\u5f15\u5217\u4e0a\u6709\u8ba1\u7b97<\/h4>\n<p>\u5f53\u6211\u4eec\u7528\u4e3b\u952e\u505a\u6761\u4ef6\u65f6\uff0c\u8d70\u7d22\u5f15\u4e86\uff1a<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044240487\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>\u800c\u5f53id\u5217\u4e0a\u9762\u6709\u8ba1\u7b97\uff0c\u6bd4\u5982\uff1a<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044240488\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>\u53ef\u4ee5\u770b\u5230\u8d70\u4e86\u5168\u8868\u626b\u63cf<\/p>\n<h4>\u7d22\u5f15\u5217\u4e0a\u6709\u51fd\u6570<\/h4>\n<p>\u6709\u65f6\u5019\u6211\u4eec\u5728\u67d0\u6761sql\u8bed\u53e5\u7684\u67e5\u8be2\u6761\u4ef6\u4e2d\uff0c\u9700\u8981\u4f7f\u7528\u51fd\u6570\uff0c\u6bd4\u5982\uff1a\u622a\u53d6\u67d0\u4e2a\u5b57\u6bb5\u7684\u957f\u5ea6\uff1a<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044240489\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>\u4f60\u6709\u6ca1\u6709\u53d1\u73b0\uff0c\u5728\u4f7f\u7528\u8be5\u51fd\u6570\u4e4b\u540e\uff0c\u8be5sql\u8bed\u53e5\u7adf\u7136\u8d70\u4e86\u5168\u8868\u626b\u63cf\uff0c\u7d22\u5f15\u5931\u6548\u4e86<\/p>\n<h4>\u5b57\u6bb5\u7c7b\u578b\u4e0d\u540c<\/h4>\n<p>\u5728sql\u8bed\u53e5\u4e2d\u56e0\u4e3a\u5b57\u6bb5\u7c7b\u578b\u4e0d\u540c\uff0c\u800c\u5bfc\u81f4\u7d22\u5f15\u5931\u6548\u7684\u95ee\u9898\uff0c\u5f88\u5bb9\u6613\u9047\u5230\uff0c\u53ef\u80fd\u662f\u6211\u4eec\u65e5\u5e38\u5de5\u4f5c\u4e2d\u6700\u5bb9\u6613\u5ffd\u7565\u7684\u95ee\u9898\u3002<\/p>\n<p>\u5230\u5e95\u600e\u4e48\u56de\u4e8b\u5462\uff1f<\/p>\n<p>\u6211\u4eec\u770b\u4e0b\u8868\u91cc\u7684start\/_org\/_code\u5b57\u6bb5\uff0c\u5b83\u662fvarchar\u5b57\u7b26\u7c7b\u578b\u7684<\/p>\n<p>\u5728sql\u8bed\u53e5\u67e5\u8be2\u6570\u636e\u65f6\uff0c\u67e5\u8be2\u6761\u4ef6\u6211\u4eec\u53ef\u4ee5\u5199\u6210\u8fd9\u6837\uff1a<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044240490\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>\u4ece\u4e0a\u56fe\u4e2d\u770b\u5230\uff0c\u8be5\u5b57\u6bb5\u8d70\u4e86\u7d22\u5f15<\/p>\n<p>\u4f46\u5982\u679c\u5728\u5199sql\u65f6\uff0c\u4e0d\u5c0f\u5fc3\u628a\u5f15\u53f7\u4e22\u4e86\uff1a<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044240491\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>\u54a6\uff0c\u8be5sql\u8bed\u53e5\u5c45\u7136\u53d8\u6210\u5168\u8868\u626b\u63cf\u4e86\uff0c\u4e3a\u4ec0\u4e48\u7d22\u5f15\u5931\u6548\u4e86\uff1f<\/p>\n<p>\u7b54\uff1a\u56e0\u4e3a\u8fd9\u4e2a\u7d22\u5f15\u5217\u662fvarchar\u7c7b\u578b\uff0c\u800c\u4f20\u53c2\u7684\u7c7b\u578b\u662fint\uff0cmysql\u5728\u6bd4\u8f83\u4e24\u79cd\u4e0d\u540c\u7c7b\u578b\u7684\u5b57\u6bb5\u65f6\u4f1a\u5c1d\u8bd5\u628a\u8fd9\u4e24\u4e2a\u8f6c\u5316\u4e3a\u540c\u4e00\u79cd\u7c7b\u578b\uff0c\u518d\u8fdb\u884c\u6bd4\u8f83\u3002\u8fd9\u6837\u5c31\u53ef\u4ee5\u7406\u89e3\u4e3a\u5728\u5b57\u6bb5\u4e0a\u52a0\u4e86\u51fd\u6570\uff0c\u6839\u636e\u4e0a\u9762\u5206\u6790\uff0c\u7d22\u5f15\u5217\u52a0\u4e86\u51fd\u6570\u4f1a\u7d22\u5f15\u5931\u6548\u3002<\/p>\n<p>\u6bd4\u8f83\u6709\u610f\u601d\u7684\u662f\uff0c\u5982\u679cint\u7c7b\u578b\u7684id\u5b57\u6bb5\uff0c\u5728\u67e5\u8be2\u65f6\u52a0\u4e86\u5f15\u53f7\u6761\u4ef6\uff0c\u5374\u8fd8\u53ef\u4ee5\u8d70\u7d22\u5f15\uff1a<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044240492\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>\u4ece\u56fe\u4e2d\u770b\u51fa\u8be5sql\u8bed\u53e5\u786e\u5b9e\u8d70\u4e86\u7d22\u5f15\u3002int\u7c7b\u578b\u7684\u53c2\u6570\uff0c\u4e0d\u7ba1\u5728\u67e5\u8be2\u65f6\u52a0\u6ca1\u52a0\u5f15\u53f7\uff0c\u90fd\u80fd\u8d70\u7d22\u5f15\u3002<\/p>\n<p>\u8fd9\u8fd8\u79d1\u5b66\u5417\uff1f\u6709\u6ca1\u6709\u738b\u6cd5\u4e86\uff1f<\/p>\n<p>\u7b54\uff1aMySQL\u53d1\u73b0\u5982\u679c\u662fint\u7c7b\u578b\u5b57\u6bb5\u4f5c\u4e3a\u67e5\u8be2\u6761\u4ef6\u65f6\uff0c\u5b83\u4f1a\u81ea\u52a8\u5c06\u8be5\u5b57\u6bb5\u7684\u4f20\u53c2\u8fdb\u884c\u9690\u5f0f\u8f6c\u6362\uff0c\u628a\u5b57\u7b26\u4e32\u8f6c\u6362\u6210int\u7c7b\u578b\u3002<\/p>\n<p>MySQL\u4f1a\u628a\u4e0a\u9762\u5217\u5b50\u4e2d\u7684\u5b57\u7b26\u4e3212348\uff0c\u8f6c\u6362\u6210\u6570\u5b5712348\uff0c\u6240\u4ee5\u4ecd\u7136\u80fd\u8d70\u7d22\u5f15\u3002<\/p>\n<p><strong>\u4e8b\u5b9e\u4e0a\uff0c\u7d22\u5f15\u5217\u4e0a\u5bf9\u5b57\u6bb5\u505a\u4efb\u4f55\u64cd\u4f5c\u90fd\u4f1a\u5bfc\u81f4\u7d22\u5f15\u5931\u6548\uff0c\u56e0\u4e3amysq\u8ba4\u4e3a\u4efb\u4f55\u8ba1\u7b97\u6216\u8005\u51fd\u6570\u90fd\u4f1a\u6539\u53d8\u7d22\u5f15\u7684\u5b9e\u9645\u6548\u679c\uff0c\u5982\u679c\u7ee7\u7eed\u4f7f\u7528\u7d22\u5f15\u53ef\u80fd\u4f1a\u9020\u6210\u7ed3\u679c\u4e0d\u51c6\u786e\u3002<\/strong><\/p>\n<h4>like\u5de6\u8fb9\u5305\u542b%<\/h4>\n<p>\u8fd9\u4e2a\u76f8\u4fe1\u6709\u70b9\u7f16\u7a0b\u7ecf\u9a8c\u7684\u540c\u5b66\u90fd\u77e5\u9053,\u8fd9\u91cc\u5c31\u4e0d\u4e3e\u4f8b\u8bf4\u660e\u4e86\u3002\u4f46\u662f\u4e3a\u4ec0\u4e48\u7d22\u5f15\u4f1a\u5931\u6548\u5462\uff1f<\/p>\n<p>\u7b54\uff1a\u5176\u5b9e\u5f88\u597d\u7406\u89e3\uff0c\u7d22\u5f15\u5c31\u50cf\u5b57\u5178\u4e2d\u7684\u76ee\u5f55\u3002\u4e00\u822c\u76ee\u5f55\u662f\u6309\u5b57\u6bcd\u6216\u8005\u62fc\u97f3\u4ece\u5c0f\u5230\u5927\uff0c\u4ece\u5de6\u5230\u53f3\u6392\u5e8f\uff0c\u662f\u6709\u987a\u5e8f\u7684\u3002<\/p>\n<p>\u6211\u4eec\u5728\u67e5\u76ee\u5f55\u65f6\uff0c\u901a\u5e38\u4f1a\u5148\u4ece\u5de6\u8fb9\u7b2c\u4e00\u4e2a\u5b57\u6bcd\u8fdb\u884c\u5339\u5bf9\uff0c\u5982\u679c\u76f8\u540c\uff0c\u518d\u5339\u5bf9\u5de6\u8fb9\u7b2c\u4e8c\u4e2a\u5b57\u6bcd\uff0c\u5982\u679c\u518d\u76f8\u540c\u5339\u5bf9\u5176\u4ed6\u7684\u5b57\u6bcd\uff0c\u4ee5\u6b64\u7c7b\u63a8\u3002<\/p>\n<p>\u901a\u8fc7\u8fd9\u79cd\u65b9\u5f0f\u6211\u4eec\u80fd\u5feb\u901f\u9501\u5b9a\u4e00\u4e2a\u5177\u4f53\u7684\u76ee\u5f55\uff0c\u6216\u8005\u7f29\u5c0f\u76ee\u5f55\u7684\u8303\u56f4\u3002<\/p>\n<p>\u4f46\u5982\u679c\u4f60\u786c\u8981\u8ddf\u76ee\u5f55\u7684\u8bbe\u8ba1\u53cd\u7740\u6765\uff0c\u5148\u4ece\u5b57\u5178\u76ee\u5f55\u53f3\u8fb9\u5339\u914d\u7b2c\u4e00\u4e2a\u5b57\u6bcd\uff0c\u8fd9\u753b\u9762\u4f60\u53ef\u4ee5\u81ea\u884c\u8111\u8865\u4e00\u4e0b\uff0c\u4f60\u773c\u4e2d\u53ef\u80fd\u53ea\u5269\u4e0b\u7edd\u671b\u4e86\uff0c\u54c8\u54c8<\/p>\n<h4>\u5217\u5bf9\u6bd4<\/h4>\n<p>\u5047\u5982\u6211\u4eec\u73b0\u5728\u6709\u8fd9\u6837\u4e00\u4e2a\u9700\u6c42\uff1a\u8fc7\u6ee4\u51fa\u8868\u4e2d\u67d0\u4e24\u5217\u503c\u76f8\u540c\u7684\u8bb0\u5f55\u3002\u4f8b\u5982\uff1a<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044240493\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>\u7d22\u5f15\u5931\u6548\u4e86\u5427\uff1f\u60ca\u4e0d\u60ca\u559c\uff1f<\/p>\n<p>\u7b54\uff1a\u8868\u91cccreate\/_time\u548cupdate\/_time\u90fd\u5efa\u4e86\u7d22\u5f15\uff0c\u5355\u72ec\u67e5\u8be2\u67d0\u4e00\u5b57\u6bb5\u65f6\u90fd\u4f1a\u8d70\u7d22\u5f15\u3002\u4f46\u5982\u679c\u628a\u4e24\u4e2a\u5355\u72ec\u5efa\u4e86\u7d22\u5f15\u7684\u5217\uff0c\u7528\u6765\u505a\u5217\u5bf9\u6bd4\u65f6\u7d22\u5f15\u4f1a\u5931\u6548\u3002\u8fd9\u5176\u5b9e\u548c\u5728\u7d22\u5f15\u5217\u4e0a\u52a0\u51fd\u6570\u4e00\u4e2a\u539f\u7406\uff0cMySQL\u8ba4\u4e3a\u7d22\u5f15\u65e0\u6cd5\u6ee1\u8db3\u9700\u6c42\u3002<\/p>\n<h4>or\u548cin\u548cexist\u548cnot in\u548cnot exist<\/h4>\n<p>\u8fd9\u51e0\u4e2a\u6709\u5f02\u66f2\u540c\u5de5\u4e4b\u5904\uff0c\u5c31\u653e\u4e00\u8d77\u8bf4\u4e86\u3002\u8fd9\u91cc\u5c31\u4e0d\u50cf\u4e0a\u9762\u51e0\u79cd\u60c5\u51b5100%\u4e0d\u8d70\u7d22\u5f15\u4e86\uff0c\u800c\u662f\u6709\u65f6\u5019\u4f1a\u8d70\u7d22\u5f15\uff0c\u6709\u65f6\u5019\u4e0d\u8d70\u7d22\u5f15\u3002\u5230\u5e95\u8d70\u4e0d\u8d70\uff1f\u6210\u672c\u8ba1\u7b97\u8bf4\u4e86\u7b97\u3002<\/p>\n<h2>\u6210\u672c\u8ba1\u7b97<\/h2>\n<p>\u67e5\u8be2\u4f18\u5316\u5668\u662f MySQL \u7684\u6838\u5fc3\u5b50\u7cfb\u7edf\u4e4b\u4e00\uff0c\u6210\u672c\u8ba1\u7b97\u53c8\u662f\u67e5\u8be2\u4f18\u5316\u5668\u7684\u6838\u5fc3\u903b\u8f91\u3002<\/p>\n<p>\u5168\u8868\u626b\u63cf\u6210\u672c\u4f5c\u4e3a\u53c2\u7167\u7269\uff0c\u7528\u4e8e\u548c\u8868\u7684\u5176\u5b83\u8bbf\u95ee\u65b9\u5f0f\u7684\u6210\u672c\u505a\u5bf9\u6bd4\u3002\u4efb\u4f55\u4e00\u79cd\u8bbf\u95ee\u65b9\u5f0f\uff0c\u53ea\u8981\u6210\u672c\u8d85\u8fc7\u4e86\u5168\u8868\u626b\u63cf\u6210\u672c\uff0c\u5c31\u4e0d\u4f1a\u88ab\u4f7f\u7528\u3002<\/p>\n<p>\u57fa\u4e8e\u5168\u8868\u626b\u63cf\u6210\u672c\u7684\u91cd\u8981\u5730\u4f4d\uff0c\u8981\u8bb2\u6e05\u695a MySQL \u7684\u6210\u672c\u8ba1\u7b97\u903b\u8f91\uff0c\u4ece\u5168\u8868\u626b\u63cf\u6210\u672c\u8ba1\u7b97\u5f00\u59cb\u662f\u4e2a\u4e0d\u9519\u7684\u9009\u62e9\u3002<\/p>\n<h4>\u5168\u8868\u626b\u63cf\u6210\u672c\u8ba1\u7b97<\/h4>\n<h5>\u5b9a\u4e49<\/h5>\n<p>\u6211\u4eec\u5148\u6765\u770b\u4e00\u4e0bMysql\u6e90\u7801\u91cc\u6210\u672c\u8ba1\u7b97\u7684\u5b9a\u4e49\uff1a<\/p>\n<pre><code>class Cost_estimate {\n private:\n  \/\/ cost of I\/O operations\n  double io_cost;\n  \/\/ cost of CPU operations\n  double cpu_cost;\n  \/\/ cost of remote operations\n  double import_cost;\n  \/\/ memory used (bytes)\n  double mem_cost;\n  ......\n}\n\n<\/code><\/pre>\n<p>\u4ece\u4e0a\u9762\u4ee3\u7801\u53ef\u4ee5\u770b\u5230\uff0cMySQL \u6210\u672c\u8ba1\u7b97\u6a21\u578b\u5b9a\u4e49\u4e86\u56db\u79cd\u6210\u672c\uff1a<\/p>\n<ul>\n<li>IO \u6210\u672c\uff1a\u4ece\u78c1\u76d8\u6216\u5185\u5b58\u8bfb\u53d6\u6570\u636e\u9875\u7684\u6210\u672c\u3002<\/li>\n<li>CPU \u6210\u672c\uff1a\u8bbf\u95ee\u8bb0\u5f55\u9700\u8981\u6d88\u8017\u7684 CPU \u6210\u672c\u3002<\/li>\n<li>\u5bfc\u5165\u6210\u672c\uff1a\u8fd9\u4e00\u9879\u4e00\u76f4\u6ca1\u88ab\u4f7f\u7528\uff0c\u5148\u5ffd\u7565\u3002<\/li>\n<li>\u5185\u5b58\u6210\u672c\uff1a\u8fd9\u4e00\u9879\u6307\u7684\u662f\u5360\u7528\u5185\u5b58\u5b57\u8282\u6570\uff0c\u8ba1\u7b97 MRR\uff08Multi Range Read\uff09\u65b9\u5f0f\u8bfb\u53d6\u6570\u636e\u7684\u6210\u672c\u65f6\u624d\u4f1a\u7528\u5230\uff0c\u4e5f\u5148\u5ffd\u7565\u3002<\/li>\n<\/ul>\n<p>\u5168\u8868\u626b\u63cf\u7684\u6210\u672c\u5c31\u53ea\u5269 IO \u6210\u672c\u3001CPU \u6210\u672c\u8fd9\u4e24\u9879\u4e86<\/p>\n<h5>\u8ba1\u7b97\u6210\u672c<\/h5>\n<p>\u6211\u4eec\u5148\u4ece\u6574\u4f53\u8ba1\u7b97\u516c\u5f0f\u5f00\u59cb\uff0c\u7136\u540e\u9010\u6b65\u62c6\u89e3\u3002<\/p>\n<p><strong>\u5168\u8868\u626b\u63cf\u6210\u672c =io\/_cost+ 1.1 +cpu\/_cost+ 1<\/strong>\u3002<\/p>\n<p>io\/_cost \u540e\u9762\u76841.1\u662f\u786c\u7f16\u7801\u76f4\u63a5\u52a0\u5230 IO \u6210\u672c\u4e0a\u7684\uff1bcpu\/_cost \u540e\u9762\u76841\u4e5f\u662f\u786c\u7f16\u7801\u7684\uff0c\u76f4\u63a5\u52a0\u5230 CPU \u6210\u672c\u4e0a\u3002\u4ee3\u7801\u91cc\u957f\u8fd9\u6837\uff1a<\/p>\n<pre><code>int test_quick_select(...) {\n  ......\n  double scan_time =\n    cost_model-&gt;row_evaluate_cost(static_cast&lt;double&gt;(records)) \n    + 1 \/* cpu_cost \u540e\u9762\u7684 + 1 *\/; \n  Cost_estimate cost_est = table-&gt;file-&gt;table_scan_cost();\n  \n  \/\/ io_cost \u540e\u9762\u7684 + 1.1\n  cost_est.add_io(1.1);\n  ......\n}\n\n<\/code><\/pre>\n<p>\u5173\u4e8e\u8fd9\u4e24\u4e2a\u786c\u7f16\u7801\u7684\u503c\uff0c\u4ee3\u7801\u91cc\u6ca1\u6709\u6ce8\u91ca\u4e3a\u4ec0\u4e48\u8981\u52a0\uff0c\u4e0d\u8fc7\u5b83\u4eec\u662f\u4e2a\u56fa\u5b9a\u503c\uff0c\u4e0d\u5f71\u54cd\u6211\u4eec\u7406\u89e3\u6210\u672c\u8ba1\u7b97\u903b\u8f91\uff0c\u5148\u5ffd\u7565\u5b83\u4eec\u3002<\/p>\n<p><strong>io\/_cost =cluster\/_page\/_count*avg\/_single\/_page\/_cost\u3002<\/strong><\/p>\n<p>cluster\/_page\/_count \u662f\u4e3b\u952e\u7d22\u5f15\u6570\u636e\u9875\u6570\u91cf\uff0c\u4ece\u8868\u7684\u7edf\u8ba1\u4fe1\u606f\u4e2d\u5f97\u5230\uff0c\u5728\u7edf\u8ba1\u4fe1\u606f\u5c0f\u8282\u4f1a\u4ecb\u7ecd\u3002<\/p>\n<p>avg\/_single\/_page_cost \u662f\u8bfb\u53d6\u4e00\u4e2a\u6570\u636e\u9875\u7684\u5e73\u5747\u6210\u672c\uff0c\u901a\u8fc7\u8ba1\u7b97\u5f97\u5230\uff0c\u516c\u5f0f\u5982\u4e0b\uff1a<\/p>\n<p><strong>avg\/_single\/_page\/_cost =pages\/_in\/_memory\/_percent<em> 0.25 +pages\/_on\/_disk_percent<\/em> 1.0<\/strong>\u3002<\/p>\n<p>pages\/_in\/_memory_percent \u662f\u4e3b\u952e\u7d22\u5f15\u5df2\u7ecf\u52a0\u8f7d\u5230 Buffer Pool\u4e2d\u7684\u53f6\u7ed3\u70b9\u5360\u6240\u6709\u53f6\u7ed3\u70b9\u7684\u6bd4\u4f8b\uff0c\u7528\u5c0f\u6570\u8868\u793a\uff08\u53d6\u503c\u8303\u56f4 0.0 ~ 1.0\uff09\uff0c\u4f8b\u5982\uff1a80% \u8868\u793a\u4e3a 0.8\u3002\u6570\u636e\u9875\u5728\u5185\u5b58\u4e2d\u7684\u6bd4\u4f8b\u5c0f\u8282\u4f1a\u4ecb\u7ecd\u5177\u4f53\u8ba1\u7b97\u903b\u8f91\u3002<\/p>\n<p>pages\/_on\/_disk\/_percent \u662f\u4e3b\u952e\u7d22\u5f15\u5728\u78c1\u76d8\u6587\u4ef6\u4e2d\u7684\u53f6\u7ed3\u70b9\u5360\u6240\u6709\u53f6\u7ed3\u70b9\u7684\u6bd4\u4f8b\uff0c\u901a\u8fc71 &#8211; pages\/_in\/_memory\/_percent\u8ba1\u7b97\u5f97\u5230\u3002<\/p>\n<p>0.25\u662f\u6210\u672c\u5e38\u6570 memory\/_block\/_read_cost\u7684\u9ed8\u8ba4\u503c\uff0c\u8868\u793a\u4ece Buffer Pool \u4e2d\u7684\u4e00\u4e2a\u6570\u636e\u9875\u8bfb\u53d6\u6570\u636e\u7684\u6210\u672c\u3002<\/p>\n<p>1.0\u662f\u6210\u672c\u5e38\u6570io\/_block\/_read_cost\u7684\u9ed8\u8ba4\u503c\uff0c\u8868\u793a\u628a\u78c1\u76d8\u6587\u4ef6\u4e2d\u7684\u4e00\u4e2a\u6570\u636e\u9875\u52a0\u8f7d\u5230 Buffer Pool \u7684\u6210\u672c\uff0c\u52a0\u4e0a\u4ece Buffer Pool \u4e2d\u7684\u8be5\u6570\u636e\u9875\u8bfb\u53d6\u6570\u636e\u7684\u6210\u672c\u3002<\/p>\n<p><strong>cpu\/_cost = n\/_rows * 0.1<\/strong>\u3002<\/p>\n<p>n_rows \u662f\u8868\u4e2d\u8bb0\u5f55\u7684\u6570\u91cf\uff0c\u4ece\u8868\u7684\u7edf\u8ba1\u4fe1\u606f\u4e2d\u5f97\u5230\uff0c\u5728\u7edf\u8ba1\u4fe1\u606f\u5c0f\u8282\u4f1a\u4ecb\u7ecd\u3002<\/p>\n<p>0.1\u662f\u6210\u672c\u5e38\u6570row\/_evaluate\/_cost\u7684\u9ed8\u8ba4\u503c\uff0c\u8868\u793a\u8bbf\u95ee\u4e00\u6761\u8bb0\u5f55\u7684 CPU \u6210\u672c\u3002<\/p>\n<p>\u6709\u4e86\u4e0a\u9762\u8fd9\u4e9b\u516c\u5f0f\uff0c\u6211\u4eec\u901a\u8fc7\u4e00\u4e2a\u5177\u4f53\u4f8b\u5b50\u8d70\u4e00\u904d\u5168\u8868\u626b\u63cf\u6210\u672c\u8ba1\u7b97\u7684\u8fc7\u7a0b\u3002<\/p>\n<p>\u5047\u8bbe\u4e00\u4e2a\u8868\u6709 15228 \u6761\u8bb0\u5f55\uff0c\u4e3b\u952e\u7d22\u5f15\u6570\u636e\u9875\u7684\u6570\u91cf\u4e3a 739\uff0c\u4e3b\u952e\u7d22\u5f15\u6570\u636e\u9875\u5df2\u7ecf\u5168\u90e8\u52a0\u8f7d\u5230 Buffer Pool\uff08pages\/_in\/_memory_percent = 1.0\uff09\uff0c\u4e0b\u9762\u6211\u4eec\u5f00\u59cb\u8ba1\u7b97\u8fc7\u7a0b\uff1a<\/p>\n<ul>\n<li>pages\/_on\/_disk\/_percent = 1 -pages\/_in\/_memory\/_percent(1.0) =<strong>0.0<\/strong>\u3002<\/li>\n<li>avg\/_single\/_page\/_cost =pages\/_in\/_memory\/_percent(1.0) *0.25+pages\/_on\/_disk_percent(0.0) *1.0=<strong>0.25<\/strong>\u3002<\/li>\n<li>io\/_cost =cluster\/_page\/_count(739) *avg\/_single\/_page\/_cost(0.25) =184.75\u3002<\/li>\n<li>cpu\/_cost =n\/_rows(15228) * 0.1 =1522.8\u3002<\/li>\n<li>\u5168\u8868\u626b\u63cf\u6210\u672c =io\/_cost(184.75) +1.1+cpu\/_cost(1522.8) +1=1709.55<\/li>\n<\/ul>\n<h5>\u7edf\u8ba1\u4fe1\u606f<\/h5>\n<p>\u5168\u8868\u626b\u63cf\u6210\u672c\u8ba1\u7b97\u8fc7\u7a0b\u4e2d\uff0c\u7528\u5230\u4e86\u4e3b\u952e\u7d22\u5f15\u6570\u636e\u9875\u6570\u91cf\u3001\u8868\u4e2d\u8bb0\u5f55\u6570\u91cf\uff0c\u8fd9\u4e24\u4e2a\u6570\u636e\u90fd\u6765\u6e90 InnoDB \u7684\u8868\u7edf\u8ba1\u4fe1\u606f\u3002<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044240494\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>clustered\/_index\/_size\u5c31\u662f\u4e3b\u952e\u7d22\u5f15\u6570\u636e\u9875\u6570\u91cf\uff0cn_rows\u662f\u8868\u4e2d\u8bb0\u5f55\u6570\u91cf\u3002<\/p>\n<h5>\u6570\u636e\u9875\u5728\u5185\u5b58\u4e2d\u7684\u6bd4\u4f8b<\/h5>\n<p><strong>avg\/_single\/_page\/_cost =pages\/_in\/_memory\/_percent<em> 0.25 +pages\/_on\/_disk_percent<\/em> 1.0<\/strong>\u3002<\/p>\n<p>\u4e0a\u9762\u7684\u516c\u5f0f\u7528\u4e8e\u8ba1\u7b97\u8bfb\u53d6\u4e00\u4e2a\u6570\u636e\u9875\u7684\u5e73\u5747\u6210\u672c\uff0cpages\/_in\/_memory_percent \u662f\u4e3b\u952e\u7d22\u5f15\u5df2\u7ecf\u52a0\u8f7d\u5230 Buffer Pool \u4e2d\u7684\u53f6\u7ed3\u70b9\u5360\u6240\u6709\u53f6\u7ed3\u70b9\u7684\u6bd4\u4f8b\u3002<\/p>\n<p>\u8ba1\u7b97\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n<pre><code>inline double index_pct_cached(const dict_index_t *index) {\n  \/\/ \u7d22\u5f15\u53f6\u7ed3\u70b9\u6570\u91cf\n  const ulint n_leaf = index-&gt;stat_n_leaf_pages;\n  ......\n  \/\/ \u5df2\u7ecf\u52a0\u8f7d\u5230 Buffer Pool \u4e2d\u7684\u53f6\u7ed3\u70b9\u6570\u91cf\n  const uint64_t n_in_mem =\n      buf_stat_per_index-&gt;get(index_id_t(index-&gt;space, index-&gt;id));\n  \/\/ \u5df2\u52a0\u8f7d\u5230 Buffer Pool \u4e2d\u7684\u53f6\u7ed3\u70b9 [\u9664\u4ee5] \u7d22\u5f15\u53f6\u7ed3\u70b9\u6570\u91cf\n  const double ratio = static_cast&lt;double&gt;(n_in_mem) \/ n_leaf;\n  \/\/ \u53d6\u503c\u53ea\u80fd\u5728 0.0 ~ 1.0 \u4e4b\u95f4\n  return (std::max(std::min(ratio, 1.0), 0.0));\n}\n\n<\/code><\/pre>\n<p>InnoDB \u5728\u5185\u5b58\u4e2d\u7ef4\u62a4\u4e86\u4e00\u4e2a\u54c8\u5e0c\u8868\uff08buf\/_stat\/_per\/_index-&gt;m\/_store\uff09\uff0ckey \u662f\u8868\u540d\uff0cvalue \u662f\u8868\u7684\u4e3b\u952e\u7d22\u5f15\u5df2\u7ecf\u52a0\u8f7d\u5230 Buffer Pool \u4e2d\u7684\u53f6\u5b50\u7ed3\u70b9\u6570\u91cf\u3002<\/p>\n<p>\u6bcf\u6b21\u4ece\u78c1\u76d8\u52a0\u8f7d\u67d0\u4e2a\u8868\u7684\u4e3b\u952e\u7d22\u5f15\u7684\u4e00\u4e2a\u53f6\u5b50\u7ed3\u70b9\u6570\u636e\u9875\u5230 Buffer Pool \u4e2d\uff0c\u8be5\u8868\u5728buf\/_stat\/_per\/_index-&gt;m\/_store\u4e2d\u5bf9\u5e94\u7684 value \u503c\u5c31\u52a0\u4e00\u3002<\/p>\n<p>\u4ece Buffer Pool \u7684 LRU \u94fe\u8868\u6dd8\u6c70\u67d0\u4e2a\u8868\u7684\u4e3b\u952e\u7d22\u5f15\u53f6\u5b50\u7ed3\u70b9\u65f6\uff0c\u8be5\u8868\u5728buf\/_stat\/_per\/_index-&gt;m\/_store\u4e2d\u5bf9\u5e94\u7684 value \u503c\u5c31\u51cf\u4e00\u3002<\/p>\n<p>\u8fd8\u6709\u5176\u5b83\u573a\u666f\uff0cbuf\/_stat\/_per\/_index-&gt;m\/_store \u4e2d\u7684 value \u503c\u4e5f\u4f1a\u53d1\u751f\u53d8\u5316\uff0c\u4e0d\u5c55\u5f00\u4e86\u3002<\/p>\n<h5>\u6210\u672c\u5e38\u6570<\/h5>\n<p>memory\/_block\/_read\/_cost \u548c io\/_block\/_read\/_cost \u8fd9\u4e24\u4e2a\u6210\u672c\u5e38\u6570\u4ece\u7cfb\u7edf\u8868mysql.engine_cost\u4e2d\u8bfb\u53d6\uff0c\u9ed8\u8ba4\u5206\u522b\u662f1.0\u548c0.25<\/p>\n<h4>\u7d22\u5f15\u6210\u672c\u8ba1\u7b97<\/h4>\n<p>\u4ee5\u5982\u4e0bsql\u4e3a\u4f8b<\/p>\n<p><img decoding=\"async\"   referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000044240495\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>\u5217resource_type\u7684\u641c\u7d22\u6761\u4ef6\u662f BETWEEN 1 AND 2\uff0c\u5f62\u6210\u7684\u626b\u63cf\u533a\u95f4\u5c31\u662f[1,2]\u3002**\u4f18\u5316\u5668\u89c4\u5b9a\uff0c\u8bfb\u53d6\u4e8c\u7ea7\u7d22\u5f15\u7684\u4e00\u4e2a\u626b\u63cf\u533a\u95f4\u7684IO\u6210\u672c\uff0c\u548c\u8bfb\u53d6\u4e00\u4e2a\u9875\u9762\u7684IO\u6210\u672c\u76f8\u540c\uff0c\u65e0\u8bba\u5b83\u5360\u7528\u591a\u5c11\u9875\u9762\u3002(\u8fd9\u4e2a\u662f\u89c4\u5b9a\uff0c\u5927\u5bb6\u8bb0\u4f4f\u5c31\u597d\u4e86)\u56e0\u6b64\u4e8c\u7ea7\u7d22\u5f15\u9875\u7684IO\u6210\u672c\u5c31\u662f1.0\u3002<\/p>\n<p>\u63a5\u4e0b\u6765\u5c31\u662f\u4f30\u7b97\u4e8c\u7ea7\u7d22\u5f15\u8fc7\u6ee4\u540e\u7684\u8bb0\u5f55\u6570\u91cf\u4e86\uff0c\u4e5f\u5c31\u662f\u6ee1\u8db3resource_type BETWEEN 1 AND 2\u7684\u8bb0\u5f55\u6570\u91cf\u3002MySQL\u662f\u8fd9\u6837\u9884\u4f30\u7684\uff1a<\/p>\n<ul>\n<li>\u627e\u5230\u7d22\u5f15\u6811\u4e2dresource_type=1\u7684\u7b2c\u4e00\u6761\u8bb0\u5f55\uff0c\u79f0\u4e3a\u8be5\u533a\u95f4\u7684\u6700\u5de6\u8bb0\u5f55\uff0c\u8fd9\u4e2a\u8fc7\u7a0b\u662f\u6781\u5feb\u7684\u3002<\/li>\n<li>\u627e\u5230\u7d22\u5f15\u6811\u4e2dresource_type=2\u7684\u6700\u540e\u4e00\u6761\u8bb0\u5f55\uff0c\u79f0\u4e3a\u8be5\u533a\u95f4\u7684\u6700\u53f3\u8bb0\u5f55\uff0c\u8fd9\u4e2a\u8fc7\u7a0b\u4e5f\u662f\u6781\u5feb\u7684\u3002<\/li>\n<li>\u4ece\u6700\u5de6\u8bb0\u5f55\u5411\u53f3\u6700\u591a\u8bfb10\u4e2a\u9875\u9762\uff0c\u5982\u679c\u8bfb\u5230\u4e86\u6700\u53f3\u8bb0\u5f55\uff0c\u5219\u7cbe\u786e\u8ba1\u7b97\u533a\u95f4\u7684\u8bb0\u5f55\u6570\u3002<\/li>\n<li>\u5982\u679c\u8bfb\u4e0d\u5230\u6700\u53f3\u8bb0\u5f55\uff0c\u8bf4\u660e\u4e2d\u95f4\u8bb0\u5f55\u6bd4\u8f83\u591a\uff0c\u5219\u91c7\u7528\u9884\u4f30\u6cd5\u3002\u5bf910\u4e2a\u9875\u9762\u4e2d\u7684\u8bb0\u5f55\u6570\u53d6\u5e73\u5747\u503c\uff0c\u7528\u5e73\u5747\u503c\u4e58\u4ee5\u533a\u95f4\u7684\u9875\u9762\u6570\u91cf\u5373\u53ef\u3002<\/li>\n<\/ul>\n<p><strong>\u7d22\u5f15\u9875\u7684Page Header\u90e8\u5206\u6709PAGE\/_N\/_RECS\u5c5e\u6027\u8bb0\u5f55\u4e86\u9875\u4e2d\u7684\u8bb0\u5f55\u6570\uff0c\u56e0\u6b64\u4e0d\u7528\u904d\u5386\u6bcf\u4e2a\u9875\u91cc\u7684\u8bb0\u5f55<\/strong><\/p>\n<p>\u53c8\u5e26\u6765\u4e00\u4e2a\u65b0\u7684\u95ee\u9898\uff0c\u5982\u4f55\u8ba1\u7b97\u8fd9\u4e2a\u533a\u95f4\u7684\u9875\u9762\u6570\u91cf\u5462\uff1f\u8fd8\u8bb0\u5f97B+\u6811\u7684\u7ed3\u6784\u5417\uff1f\u8be5\u533a\u95f4\u7684\u7b2c0\u5c42\u7684\u53f6\u5b50\u8282\u70b9\u6570\u867d\u7136\u5f88\u591a\uff0c\u96be\u4ee5\u7edf\u8ba1\uff0c\u4f46\u662f\u6211\u4eec\u53ef\u4ee5\u770b\u5b83\u4eec\u7684\u7236\u8282\u70b9\u554a\uff0c\u8fd9\u4e24\u4e2a\u7d22\u5f15\u9875\u7684\u76ee\u5f55\u9879\u5927\u6982\u7387\u662f\u4f1a\u5728\u540c\u4e00\u4e2a\u7236\u8282\u70b9\u9875\u4e2d\u7684\uff0c\u5728\u7236\u8282\u70b9\u9875\u4e2d\u7edf\u8ba1\u533a\u95f4\u5185\u6709\u591a\u5c11\u9875\u9762\u5c31\u975e\u5e38\u5bb9\u6613\u4e86\uff0c\u5176\u5b9e\u5c31\u662f\u7edf\u8ba1\u4e24\u4e2a\u76ee\u5f55\u9879\u4e4b\u95f4\u9694\u4e86\u591a\u5c11\u4e2a\u76ee\u5f55\u9879\u8bb0\u5f55\u3002<\/p>\n<p>\u8fd9\u91cc\uff0c\u6211\u4eec\u5047\u8bbe\u6ee1\u8db3resource_type BETWEEN 1 AND 2\u7684\u8bb0\u5f55\u6570\u662f15000\u4e2a\uff0c\u5219\u4e8c\u7ea7\u7d22\u5f15\u8bb0\u5f55\u7684CPU\u6210\u672c\u662f15000 * 0.2 + 0.01 = 3000.01<\/p>\n<p>\u63a5\u4e0b\u6765\u5c31\u662f\u8fd915000\u6761\u8bb0\u5f55\u56de\u8868\u7684IO\u6210\u672c\u4e86\uff0c<strong>MySQL\u89c4\u5b9a\uff0c\u6bcf\u6b21\u56de\u8868\u7684IO\u6210\u672c\u76f8\u5f53\u4e8e\u8bfb\u53d6\u4e00\u4e2a\u9875\u9762\u7684IO\u6210\u672c<\/strong>\uff0c\u4e8c\u7ea7\u7d22\u5f15\u8fc7\u6ee4\u51fa\u7684\u8bb0\u5f55\u6570\u91cf\u5c31\u662f\u56de\u8868\u7684\u6b21\u6570\u3002\u56e0\u6b64\uff0c\u56de\u8868\u7684IO\u6210\u672c\u662f15000 * 1.0 = 15000.0\u3002<\/p>\n<p>\u7efc\u4e0a\u6240\u8ff0\uff0c\u4f7f\u7528\u7d22\u5f15\u7684\u6267\u884c\u6210\u672c\u662f\uff1a<\/p>\n<ul>\n<li>IO\u6210\u672c\uff1a15000.0+1.0= 15001.0<\/li>\n<li>CPU\u6210\u672c\uff1a3000.01<\/li>\n<li>\u603b\u7d22\u5f15\u6210\u672c\uff1a15001.0+3000.01=18001.01<\/li>\n<\/ul>\n<p>\u901a\u8fc7\u548c\u5168\u8868\u626b\u63cf\u5bf9\u6bd4\uff0c\u5b70\u4f18\u5b70\u52a3\u4e00\u76ee\u4e86\u7136\u3002\u8fd9\u4e0b\u662f\u4e0d\u662f\u6e05\u695a\u591a\u4e86\uff1f<\/p>\n<h2>\u5c0f\u7ed3<\/h2>\n<p>MySQL\u6267\u884c\u4e00\u6761\u67e5\u8be2\u8bed\u53e5\u7684\u6d41\u7a0b\u662f\u8fd9\u6837\u7684\uff0c\u5148\u627e\u5230\u6240\u6709\u53ef\u80fd\u7528\u5230\u7684\u7d22\u5f15\uff0c\u7136\u540e\u8ba1\u7b97\u5168\u8868\u626b\u63cf\u7684\u6210\u672c\uff0c\u7136\u540e\u5206\u522b\u8ba1\u7b97\u4f7f\u7528\u4e0d\u540c\u7d22\u5f15\u7684\u6210\u672c\uff0c\u6700\u7ec8\u9009\u62e9\u6210\u672c\u6700\u4f4e\u7684\u65b9\u6848\u6765\u6267\u884c\u67e5\u8be2\u3002\u8fd9\u91cc\u8bf4\u7684\u6210\u672c\u5176\u5b9e\u662f\u7531IO\u6210\u672c\u548cCPU\u6210\u672c\u7ec4\u6210\u7684\uff0c\u5bf9\u4e8eInnoDB\u5f15\u64ce\u6765\u8bf4\uff0c\u8bfb\u53d6\u4e00\u4e2a\u9875\u7684IO\u6210\u672c\u662f1.0\uff0c\u8bfb\u53d6\u4e00\u6761\u8bb0\u5f55\u5e76\u68c0\u6d4b\u662f\u5426\u7b26\u5408\u641c\u7d22\u6761\u4ef6\u7684CPU\u6210\u672c\u662f0.2\u3002\u5168\u8868\u626b\u63cf\u7684\u6210\u672c\u8ba1\u7b97\u975e\u5e38\u7b80\u5355\uff0c\u6839\u636e\u8868\u7684\u7edf\u8ba1\u6570\u636e\u5373\u53ef\u9884\u4f30\u51fa\u805a\u7c07\u7d22\u5f15\u5360\u7528\u7684\u9875\u9762\u6570\u548c\u8868\u7684\u603b\u8bb0\u5f55\u6570\u3002\u5bf9\u4e8e\u4e8c\u7ea7\u7d22\u5f15\u7684\u8f85\u52a9\u67e5\u8be2\uff0c\u9664\u4e86\u8fc7\u6ee4\u4e8c\u7ea7\u7d22\u5f15\u672c\u8eab\u7684IO\u6210\u672c+CPU\u6210\u672c\uff0c\u8fd8\u6709\u56de\u8868\u7684IO\u6210\u672c+CPU\u6210\u672c\uff0c<\/p>\n<blockquote>\n<p>\u4f5c\u8005\uff1a\u4eac\u4e1c\u7269\u6d41 \u5218\u6d77\u8fd0<\/p>\n<p>\u6765\u6e90\uff1a\u4eac\u4e1c\u4e91\u5f00\u53d1\u8005\u793e\u533a \u81ea\u733f\u5176\u8bf4Tech \u8f6c\u8f7d\u8bf7\u6ce8\u660e\u6765\u6e90<\/p>\n<\/blockquote>\n<p><a href=\"https:\/\/segmentfault.com\/a\/1190000044240483\">https:\/\/segmentfault.com\/a\/1190000044240483<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u73b0\u8c61 \u6700\u8fd1\u6536\u5230\u4e00\u4e2a\u6162sql\u5de5\u5355,\u6162sql\u5927\u6982\u662f\u8fd9\u6837\uff1a\u201cselect xxx from tabel where  [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[4],"tags":[],"class_list":["post-10008306","post","type-post","status-publish","format-standard","hentry","category-share"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/posts\/10008306","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=10008306"}],"version-history":[{"count":0,"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/posts\/10008306\/revisions"}],"wp:attachment":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=10008306"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=10008306"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=10008306"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}