{"id":10007002,"date":"2022-12-22T15:38:07","date_gmt":"2022-12-22T07:38:07","guid":{"rendered":"https:\/\/ityet.com\/?p=10007002"},"modified":"2022-12-22T15:38:07","modified_gmt":"2022-12-22T07:38:07","slug":"mysql%e7%b4%a2%e5%bc%95%e4%b8%8b%e6%8e%a8%e7%9f%a5%e8%af%86%e5%88%86%e4%ba%ab","status":"publish","type":"post","link":"https:\/\/itmax.cn\/?p=10007002","title":{"rendered":"MySql\u7d22\u5f15\u4e0b\u63a8\u77e5\u8bc6\u5206\u4eab"},"content":{"rendered":"<p><strong>\u4f5c\u8005\uff1a\u5218\u9093\u5fe0<\/strong><\/p>\n<p>Mysql \u662f\u5927\u5bb6\u6700\u5e38\u7528\u7684\u6570\u636e\u5e93\uff0c\u4e0b\u9762\u4e3a\u5927\u5bb6\u5e26\u6765 mysql \u7d22\u5f15\u4e0b\u63a8\u77e5\u8bc6\u70b9\u7684\u5206\u4eab\uff0c\u4ee5\u4fbf\u5de9\u56fa mysql \u57fa\u7840\u77e5\u8bc6\uff0c\u5982\u6709\u9519\u8bef\uff0c\u8fd8\u8bf7\u5404\u4f4d\u5927\u4f6c\u4eec\u6307\u6b63\u3002<\/p>\n<h2>1 \u4ec0\u4e48\u662f\u7d22\u5f15\u4e0b\u63a8<\/h2>\n<p>\u7d22\u5f15\u4e0b\u63a8 (Index Condition Pushdown\uff0c\u7d22\u5f15\u6761\u4ef6\u4e0b\u63a8\uff0c\u7b80\u79f0 ICP)\uff0c\u662f MySQL5.6 \u7248\u672c\u7684\u65b0\u7279\u6027\uff0c\u5b83\u53ef\u4ee5\u5728\u5bf9\u8054\u5408\u7d22\u5f15\u904d\u5386\u8fc7\u7a0b\u4e2d\uff0c\u5bf9\u7d22\u5f15\u4e2d\u5305\u542b\u7684\u6240\u6709\u5b57\u6bb5\u5148\u505a\u5224\u65ad\uff0c\u8fc7\u6ee4\u6389\u4e0d\u7b26\u5408\u6761\u4ef6\u7684\u8bb0\u5f55\u4e4b\u540e\u518d\u56de\u8868\uff0c\u80fd\u6709\u6548\u7684\u51cf\u5c11\u56de\u8868\u6b21\u6570\uff08\u76ee\u524d\u6211\u4eec\u4f7f\u7528\u7684 mysql \u7248\u672c\u8f83\u9ad8\uff0c\u4e00\u822c\u5927\u5bb6\u53ef\u80fd\u611f\u89c9\u8fd9\u662f\u6b63\u5e38\u7684\uff0c\u4f46\u662f mysql5.6 \u4e4b\u524d\u90fd\u4e0d\u662f\u8fd9\u6837\u5b9e\u73b0\u7684\uff0c\u4e0b\u9762\u4f1a\u7ec6\u7ec6\u9053\u6765\uff09\u3002<\/p>\n<h3>1.1 \u9002\u7528\u6761\u4ef6<\/h3>\n<p>\u6211\u4eec\u5148\u6765\u4e86\u89e3\u4e00\u4e0b\u7d22\u5f15\u4e0b\u63a8\u7684\u4f7f\u7528\u6761\u4ef6\u53ca\u9650\u5236\uff1a<\/p>\n<ul>\n<li>\u53ea\u652f\u6301 select\u3002<\/li>\n<li>\u5f53\u9700\u8981\u8bbf\u95ee\u5168\u8868\u65f6\uff0cICP \u7528\u4e8e range\uff0cref\uff0ceq_ref \u548c ref_or_null \u8bbf\u95ee\u7c7b\u578b\u3002<\/li>\n<li>ICP \u53ef\u7528\u4e8e InnoDB \u548c MyISAM \u8868\uff0c\u5305\u62ec\u5206\u533a\u7684 InnoDB \u548c MyISAM \u8868\u3002\uff085.6 \u7248\u672c\u4e0d\u9002\u7528\u5206\u533a\u8868\u67e5\u8be2\uff0c5.7 \u7248\u672c\u540e\u53ef\u4ee5\u7528\u4e8e\u5206\u533a\u8868\u67e5\u8be2\uff09\u3002<\/li>\n<li>\u5bf9\u4e8e InnDB \u5f15\u64ce\u53ea\u9002\u7528\u4e8e\u4e8c\u7ea7\u7d22\u5f15\uff08\u4e5f\u53eb\u8f85\u52a9\u7d22\u5f15\uff09\uff0c\u56e0\u4e3a InnDB \u7684\u805a\u7c07\u7d22\u5f15\u4f1a\u5c06\u6574\u884c\u6570\u636e\u8bfb\u5230 InnDB \u7684\u7f13\u51b2\u533a\uff0c\u8fd9\u6837\u4e00\u6765\u7d22\u5f15\u6761\u4ef6\u4e0b\u63a8\u7684\u4e3b\u8981\u76ee\u7684\u51cf\u5c11 IO \u6b21\u6570\u5c31\u5931\u53bb\u4e86\u610f\u4e49\u3002\u56e0\u4e3a\u6570\u636e\u5df2\u7ecf\u5728\u5185\u5b58\u4e2d\u4e86\uff0c\u4e0d\u518d\u9700\u8981\u53bb\u8bfb\u53d6\u4e86\u3002<\/li>\n<li>\u5728\u865a\u62df\u751f\u6210\u5217\u4e0a\u521b\u5efa\u7684\u8f85\u52a9\u7d22\u5f15\u4e0d\u652f\u6301 ICP\uff08\u6ce8\uff1aInnoDB \u652f\u6301\u865a\u62df\u751f\u6210\u5217\u7684\u8f85\u52a9\u7d22\u5f15\uff09\u3002<\/li>\n<li>\u4f7f\u7528\u4e86\u5b50\u67e5\u8be2\u7684\u6761\u4ef6\u65e0\u6cd5\u4e0b\u63a8\u3002<\/li>\n<li>\u4f7f\u7528\u5b58\u50a8\u8fc7\u7a0b\u6216\u51fd\u6570\u7684\u6761\u4ef6\u65e0\u6cd5\u4e0b\u63a8\uff08\u56e0\u4e3a\u56e0\u4e3a\u5b58\u50a8\u5f15\u64ce\u6ca1\u6709\u8c03\u7528\u5b58\u50a8\u8fc7\u7a0b\u6216\u51fd\u6570\u7684\u80fd\u529b\uff09\u3002<\/li>\n<li>\u89e6\u53d1\u6761\u4ef6\u65e0\u6cd5\u4e0b\u63a8\u3002\uff08\u6709\u5173\u89e6\u53d1\u6761\u4ef6\u7684\u4fe1\u606f\uff0c\u8bf7\u53c2\u9605\u5b98\u65b9\u8d44\u6599\uff1aSection 8.2.2.3, \u201cOptimizing Subqueries with the EXISTS Strategy\u201d.\u3002\uff09<\/li>\n<\/ul>\n<h3>1.2 \u539f\u7406\u4ecb\u7ecd<\/h3>\n<p>\u9996\u5148\uff0c\u6211\u4eec\u5927\u81f4\u56de\u987e\u4e0b mysql \u7684\u57fa\u672c\u67b6\u6784\uff1a<\/p>\n<p><img decoding=\"async\" referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000043133215\" alt=\"\" title=\"\" loading=\"lazy\">  <\/p>\n<p>MySQL \u57fa\u672c\u7684\u67b6\u6784\u793a\u4f8b\u56fe<\/p>\n<p>MySQL \u670d\u52a1\u5c42\u4e3b\u8981\u8d1f\u8d23 SQL \u8bed\u6cd5\u89e3\u6790\u3001\u751f\u6210\u6267\u884c\u8ba1\u5212\u7b49\uff0c\u5e76\u8c03\u7528\u5b58\u50a8\u5f15\u64ce\u5c42\u53bb\u6267\u884c\u6570\u636e\u7684\u5b58\u50a8\u548c\u67e5\u8be2\u3002  <br \/>\u7d22\u5f15\u4e0b\u63a8\u7684\u4e0b\u63a8\u5176\u542b\u4e49\u5c31\u662f\u6307\u5c06\u90e8\u5206\u4e0a\u5c42\uff08\u670d\u52a1\u5c42\uff09\u8d1f\u8d23\u7684\u4e8b\u60c5\uff0c\u4ea4\u7ed9\u4e86\u4e0b\u5c42\uff08\u5f15\u64ce\u5c42\uff09\u53bb\u5904\u7406\u3002  <br \/>\u5728 MySql 5.6 \u7248\u672c\u4e4b\u524d\u6ca1\u6709\u7d22\u5f15\u4e0b\u63a8\u8fd9\u4e2a\u529f\u80fd\uff0c\u4ece 5.6 \u7248\u672c\u540e\u624d\u52a0\u4e0a\u4e86\u8fd9\u4e2a\u4f18\u5316\u9879\u3002\u6211\u4eec\u5148\u7b80\u5355\u5bf9\u6bd4\u4e00\u4e0b\u4f7f\u7528\u548c\u672a\u4f7f\u7528 ICP \u4e24\u79cd\u60c5\u51b5\u4e0b\uff0cMySql \u7684\u67e5\u8be2\u8fc7\u7a0b\u5427\u3002  <\/p>\n<p><strong>1) \u672a\u4f7f\u7528 ICP \u7684\u60c5\u51b5\u4e0b\uff1a<\/strong><\/p>\n<ul>\n<li>\u5b58\u50a8\u5f15\u64ce\u8bfb\u53d6\u7d22\u5f15\u8bb0\u5f55\uff1b<\/li>\n<li>\u6839\u636e\u7d22\u5f15\u4e2d\u7684\u4e3b\u952e\u503c\uff0c\u5b9a\u4f4d\u5e76\u8bfb\u53d6\u5b8c\u6574\u7684\u884c\u8bb0\u5f55\uff1b<\/li>\n<li>\u5b58\u50a8\u5f15\u64ce\u628a\u8bb0\u5f55\u4ea4\u7ed9 Server \u5c42\u53bb\u68c0\u6d4b\u8be5\u8bb0\u5f55\u662f\u5426\u6ee1\u8db3 WHERE \u6761\u4ef6\u3002<\/li>\n<\/ul>\n<p><strong>2) \u4f7f\u7528 ICP \u7684\u60c5\u51b5\u4e0b\uff1a<\/strong><\/p>\n<ul>\n<li>\u5b58\u50a8\u5f15\u64ce\u8bfb\u53d6\u7d22\u5f15\u8bb0\u5f55\uff08\u4e0d\u662f\u5b8c\u6574\u7684\u884c\u8bb0\u5f55\uff09\uff1b<\/li>\n<li>\u5224\u65ad WHERE \u6761\u4ef6\u90e8\u5206\u80fd\u5426\u7528\u7d22\u5f15\u4e2d\u7684\u5217\u6765\u505a\u68c0\u67e5\uff0c\u6761\u4ef6\u4e0d\u6ee1\u8db3\uff0c\u5219\u5904\u7406\u4e0b\u4e00\u884c\u7d22\u5f15\u8bb0\u5f55\uff1b<\/li>\n<li>\u6761\u4ef6\u6ee1\u8db3\uff0c\u4f7f\u7528\u7d22\u5f15\u4e2d\u7684\u4e3b\u952e\u53bb\u5b9a\u4f4d\u5e76\u8bfb\u53d6\u5b8c\u6574\u7684\u884c\u8bb0\u5f55\uff08\u5c31\u662f\u6240\u8c13\u7684\u56de\u8868\uff09\uff1b<\/li>\n<li>\u5b58\u50a8\u5f15\u64ce\u628a\u8bb0\u5f55\u4ea4\u7ed9 Server \u5c42\uff0cServer \u5c42\u68c0\u6d4b\u8be5\u8bb0\u5f55\u662f\u5426\u6ee1\u8db3 WHERE \u6761\u4ef6\u7684\u5176\u4f59\u90e8\u5206\u3002  <br \/>\u00a0<\/li>\n<\/ul>\n<h2>2 \u5177\u4f53\u793a\u4f8b<\/h2>\n<p>\u4e0a\u9762\u4ecb\u7ecd\u4e86\u57fa\u672c\u539f\u7406\uff0c\u4e0b\u9762\u4f7f\u7528\u793a\u4f8b\uff0c\u5e26\u5927\u5bb6\u66f4\u76f4\u89c2\u7684\u8fdb\u884c\u7406\u89e3\uff08\u6ce8\uff1a\u4ee5\u4e0b\u793a\u4f8b\u57fa\u4e8e InnoDB \u5b58\u50a8\u5f15\u64ce\u3002\uff09  <br \/>\u9996\u5148\uff0c\u6211\u4eec\u65b0\u5efa\u4e00\u5f20\u7528\u6237\u8868\uff08jxc_user\uff09\uff0c\u8bbe\u7f6e id \u4e3a\u4e3b\u952e\u7d22\u5f15\uff0c\u5e76\u521b\u5efa\u8054\u5408\u7d22\u5f15\uff08name, age\uff09\u3002  <\/p>\n<p><img decoding=\"async\" referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000043133216\" alt=\"\" title=\"\" loading=\"lazy\">  <\/p>\n<p>\u6211\u4eec\u5148\u770b\u4e00\u4e0b\u8be5\u8868\u4e3b\u952e\u7d22\u5f15\u7684\u5927\u81f4\u7ed3\u6784\u793a\u4f8b\uff1a  <br \/>\u00a0<\/p>\n<p><img decoding=\"async\" referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000043133217\" alt=\"\" title=\"\" loading=\"lazy\">  <\/p>\n<p>\u4e3b\u952e\u7d22\u5f15\u7ed3\u6784\u793a\u4f8b\u56fe<\/p>\n<p>\u7136\u540e\u6211\u4eec\u518d\u770b\u4e00\u4e0b\u8be5\u8868\u8054\u5408\u7d22\u5f15\u7684\u5927\u81f4\u7ed3\u6784\u793a\u4f8b\uff1a  <br \/>\u00a0<\/p>\n<p><img decoding=\"async\" referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000043133218\" alt=\"\" title=\"\" loading=\"lazy\">  <\/p>\n<p>\u8054\u5408\u7d22\u5f15\u7ed3\u6784\u793a\u4f8b\u56fe<\/p>\n<p>\u5982\u679c\u73b0\u5728\u6709\u4e00\u4e2a\u9700\u6c42\uff0c\u8981\u6c42\u68c0\u7d22\u51fa\u8868\u4e2d\u540d\u5b57\u7b2c\u4e00\u4e2a\u5b57\u662f\u5f20\uff0c\u800c\u4e14\u5e74\u9f84\u7b49\u4e8e 10 \u5c81\u7684\u6240\u6709\u7528\u6237\u3002\u793a\u4f8b SQL \u8bed\u53e5\u5982\u4e0b\uff1a<\/p>\n<pre><code>\u00a0<\/code><\/pre>\n<ol>\n<li><code>select\u00a0id,name,age,tel,addr\u00a0from\u00a0jxc_user\u00a0where\u00a0name like\u00a0'\u5f20%'\u00a0and\u00a0age=10;<\/code><\/li>\n<\/ol>\n<p>\u6839\u636e\u7d22\u5f15\u6700\u5de6\u5339\u914d\u539f\u5219\uff0c\u4e0a\u9762\u8fd9\u4e2a sql \u8bed\u53e5\u5728\u67e5\u7d22\u5f15\u6811\u7684\u65f6\u5019\uff0c\u53ea\u80fd\u7528 \u201c\u5f20\u201d\uff0c\u67e5\u5230\u7b2c\u4e00\u4e2a\u6ee1\u8db3\u6761\u4ef6\u7684\u8bb0\u5f55\uff1aid \u4e3a 1\u3002  <br \/>\u90a3\u63a5\u4e0b\u6765\u6211\u4eec\u5177\u4f53\u770b\u4e00\u4e0b \u4f7f\u7528\u4e0e\u672a\u4f7f\u7528 ICP \u7684\u60c5\u51b5\u3002<\/p>\n<h3>2.1 \u672a\u4f7f\u7528 ICP \u7684\u60c5\u51b5<\/h3>\n<p>\u5728 MySQL 5.6 \u4e4b\u524d\uff0c\u5b58\u50a8\u5f15\u64ce\u6839\u636e\u8054\u5408\u7d22\u5f15\u5148\u627e\u5230 name like \u2018\u5f20 %\u2019 \u7684\u4e3b\u952e id\uff081\u30014\uff09\uff0c\u518d\u9010\u4e00\u8fdb\u884c\u56de\u8868\u626b\u63cf\uff0c\u53bb\u805a\u7c07\u7d22\u5f15\u627e\u5230\u5b8c\u6574\u7684\u884c\u8bb0\u5f55\uff0c\u8fd4\u56de server \u5c42\uff0cserver \u5c42\u62ff\u5230\u6570\u636e\u540e\uff0c\u518d\u6839\u636e\u6761\u4ef6 age=10 \u5bf9\u62ff\u5230\u7684\u6570\u636e\u8fdb\u884c\u7b5b\u9009\u3002\u5927\u81f4\u7684\u793a\u610f\u56fe\u5982\u4e0b\uff1a<\/p>\n<p><img decoding=\"async\" referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000043133219\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>\u4ece\u4e0a\u56fe\uff0c\u53ef\u4ee5\u770b\u5230\u9700\u8981\u56de\u8868\u4e24\u6b21\uff0c\u5b58\u50a8\u5f15\u64ce\u5e76\u4e0d\u4f1a\u53bb\u6309\u7167 age=10 \u8fdb\u884c\u8fc7\u6ee4\uff0c\u76f8\u5f53\u4e8e\u8054\u5408\u7d22\u5f15\u7684\u53e6\u4e00\u4e2a\u5b57\u6bb5 age \u5728\u5b58\u50a8\u5f15\u64ce\u5c42\u6ca1\u6709\u53d1\u6325\u4f5c\u7528\uff0c\u6bd4\u8f83\u6d6a\u8d39\u3002<\/p>\n<h3>2.2 \u4f7f\u7528 ICP \u7684\u60c5\u51b5<\/h3>\n<p>\u800c MySQL 5.6 \u4ee5\u540e\uff0c \u5b58\u50a8\u5f15\u64ce\u4f1a\u6839\u636e\uff08name\uff0cage\uff09\u8054\u5408\u7d22\u5f15\uff0c\u627e\u5230 name like \u2018\u5f20 %\u2019\uff0c\u7531\u4e8e\u8054\u5408\u7d22\u5f15\u4e2d\u5305\u542b age \u5217\uff0c\u6240\u4ee5\u5b58\u50a8\u5f15\u64ce\u76f4\u63a5\u518d\u8054\u5408\u7d22\u5f15\u91cc\u6309\u7167\u6761\u4ef6 age=10 \u8fdb\u884c\u8fc7\u6ee4\uff0c\u7136\u540e\u6839\u636e\u8fc7\u6ee4\u540e\u7684\u6570\u636e\u518d\u4f9d\u6b21\u8fdb\u884c\u56de\u8868\u626b\u63cf\u3002\u5927\u81f4\u7684\u793a\u610f\u56fe\u5982\u4e0b\uff1a<\/p>\n<p><img decoding=\"async\" referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000043133220\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>\u4ece\u4e0a\u56fe\uff0c\u53ef\u4ee5\u770b\u5230\u53ea\u662f id=1 \u7684\u6570\u636e\uff0c\u56de\u8868\u4e86\u4e00\u6b21\u3002<\/p>\n<p>\u9664\u6b64\u4e4b\u5916\u6211\u4eec\u8fd8\u53ef\u4ee5\u770b\u4e00\u4e0b\u6267\u884c\u8ba1\u5212\uff0c\u770b\u5230 Extra \u4e00\u5217\u91cc Using index condition\uff0c\u5c31\u662f\u7528\u5230\u4e86\u7d22\u5f15\u4e0b\u63a8\u3002<\/p>\n<p><img decoding=\"async\" referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000043133221\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<h2>3 \u63a7\u5236\u53c2\u6570<\/h2>\n<p>Mysql \u7d22\u5f15\u4e0b\u63a8\u529f\u80fd\u9ed8\u8ba4\u662f\u5f00\u542f\u7684\uff0c\u53ef\u4ee5\u7528\u7cfb\u7edf\u53c2\u6570 optimizer_switch \u6765\u63a7\u5236\u662f\u5426\u5f00\u542f\u3002  <br \/>\u67e5\u770b\u72b6\u6001\u547d\u4ee4\uff1a  <br \/>select @<a href=\"https:\/\/link.segmentfault.com\/?enc=9PAEh2upCGYcOSiuKbwr9A%3D%3D.Zg4xDVQ9gM5RkQvDXPc2Oq%2BcFG%2FmejXSMrNb03VIYbcfuca179a4xFKjVin6e6BtTJOu4iq2vGXUkkIYEX8b%2BJKWNv%2BsEmxvKcEsAjyZERdwgCjS%2FtYovEpYnu9uCmD3\" rel=\"nofollow\">@optimizer_switch<\/a>;<\/p>\n<p><img decoding=\"async\" referrerpolicy=\"no-referrer\" src=\"https:\/\/segmentfault.com\/img\/remote\/1460000043133222\" alt=\"\" title=\"\" loading=\"lazy\"><\/p>\n<p>\u5173\u95ed\u547d\u4ee4\uff1aset optimizer_switch=\u201dindex_condition_pushdown=off\u201d;  <br \/>\u5f00\u542f\u547d\u4ee4\uff1aset optimizer_switch=\u201dindex_condition_pushdown=on\u201d;<\/p>\n<h2>4 \u603b\u7ed3<\/h2>\n<p>\u56de\u8868\u64cd\u4f5c\uff1a\u5f53\u6240\u8981\u67e5\u627e\u7684\u5b57\u6bb5\u4e0d\u5728\u975e\u4e3b\u952e\u7d22\u5f15\u6811\u4e0a\u65f6\uff0c\u9700\u8981\u901a\u8fc7\u53f6\u5b50\u8282\u70b9\u7684\u4e3b\u952e\u503c\u53bb\u4e3b\u952e\u7d22\u5f15\u4e0a\u83b7\u53d6\u5bf9\u5e94\u7684\u884c\u6570\u636e\uff0c\u8fd9\u4e2a\u8fc7\u7a0b\u79f0\u4e3a\u56de\u8868\u64cd\u4f5c\u3002  <br \/>\u7d22\u5f15\u4e0b\u63a8\uff1a\u7d22\u5f15\u4e0b\u63a8\u4e3b\u8981\u662f\u51cf\u5c11\u4e86\u4e0d\u5fc5\u8981\u7684\u56de\u8868\u64cd\u4f5c\u3002\u5bf9\u4e8e\u67e5\u627e\u51fa\u6765\u7684\u6570\u636e\uff0c\u5148\u8fc7\u6ee4\u6389\u4e0d\u7b26\u5408\u6761\u4ef6\u7684\uff0c\u5176\u4f59\u7684\u518d\u53bb\u4e3b\u952e\u7d22\u5f15\u6811\u4e0a\u67e5\u627e\u3002<\/p>\n<h2>5 \u53c2\u8003\u6587\u732e<\/h2>\n<ul>\n<li><a href=\"https:\/\/link.segmentfault.com\/?enc=LtMbjxg5gMkPWOSRxOu0%2BA%3D%3D.7AkeSrOhGyl552Z8vqw16NdTA45PdQvMpjohmtOfOfMACzqz0CDt6HIKIwNrJ%2FqnF9WDSfSxSkzhrgivYEdCDPqek8eeGj1gFmQpLvq9OG%2BO21g5U%2BGP3kIjpnC8M%2BB5d6VtP3Mi8WpFBcCNhGnkFhc%2B6McTkmdhPZbJyvb0min%2BnMME1Q5m6Mu8gPokePrn\" rel=\"nofollow\">https:\/\/dev.mysql.com\/doc\/refman\/5.6\/en\/index-condition-pushdown-optimization.html<\/a><\/li>\n<li><a href=\"https:\/\/link.segmentfault.com\/?enc=VG83rJWwt5PGx3mb2ddPKg%3D%3D.l%2F7vDGtVuAJ52X3hVr7iDg1v5GkIUHvfwKcADJai%2FKdGfHLYUOsr4ditlEyFHQzw13mzR%2BI7C%2BDVhVXep8pn0N5qM%2FI1UrCEKJzfeXz%2F6ZgfpxZlIXzNHI3S6YTTJoJz3mIGjdaO%2B7UkrYFUV6vGWA%3D%3D\" rel=\"nofollow\">http:\/\/mysql.taobao.org\/monthly\/2015\/12\/08\/<\/a><\/li>\n<\/ul>\n<p><a href=\"https:\/\/segmentfault.com\/a\/1190000043133213\">https:\/\/segmentfault.com\/a\/1190000043133213<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4f5c\u8005\uff1a\u5218\u9093\u5fe0 Mysql \u662f\u5927\u5bb6\u6700\u5e38\u7528\u7684\u6570\u636e\u5e93\uff0c\u4e0b\u9762\u4e3a\u5927\u5bb6\u5e26\u6765 mysql \u7d22\u5f15\u4e0b\u63a8\u77e5\u8bc6\u70b9\u7684\u5206\u4eab\uff0c\u4ee5\u4fbf\u5de9\u56fa m [&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-10007002","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\/10007002","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=10007002"}],"version-history":[{"count":0,"href":"https:\/\/itmax.cn\/index.php?rest_route=\/wp\/v2\/posts\/10007002\/revisions"}],"wp:attachment":[{"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=10007002"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=10007002"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/itmax.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=10007002"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}