{"id":5092,"date":"2020-09-05T15:26:25","date_gmt":"2020-09-05T07:26:25","guid":{"rendered":"https:\/\/www.xttblog.com\/?p=5092"},"modified":"2020-09-05T15:28:35","modified_gmt":"2020-09-05T07:28:35","slug":"%e9%9d%a2%e8%af%95%e5%ae%98%ef%bc%9amysql%e4%ba%8b%e5%8a%a1%e9%9a%94%e7%a6%bb%e7%ba%a7%e5%88%ab%e4%b8%ad%e7%9a%84%e5%8f%af%e9%87%8d%e5%a4%8d%e8%af%bb%e8%83%bd%e9%98%b2%e5%b9%bb%e8%af%bb%e5%90%97","status":"publish","type":"post","link":"https:\/\/www.xttblog.com\/?p=5092","title":{"rendered":"\u9762\u8bd5\u5b98\uff1aMySQL\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u4e2d\u7684\u53ef\u91cd\u590d\u8bfb\u80fd\u9632\u5e7b\u8bfb\u5417?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">\u4eca\u5929\u6211\u4eec\u6765\u804a\u4e00\u804a\u4e00\u4e2a\u6bd4\u8f83\u5e38\u89c1\u4e14\u96be\u641e\u61c2\u7684\u8bdd\u9898\u3002\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u4e2d\u7684\u53ef\u91cd\u590d\u8bfb\u80fd\u9632\u5e7b\u8bfb\u5417?<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u524d\u8a00<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6bcf\u6b21\u8c08\u5230\u6570\u636e\u5e93\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\uff0c\u5927\u5bb6\u4e00\u5b9a\u4f1a\u770b\u5230\u8fd9\u5f20\u8868\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/%E4%BA%8B%E5%8A%A1%E9%9A%94%E7%A6%BB%E7%BA%A7%E5%88%AB.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u5176\u4e2d,\u53ef\u91cd\u590d\u8bfb\u8fd9\u4e2a\u9694\u79bb\u7ea7\u522b,\u6709\u6548\u5730\u9632\u6b62\u4e86\u810f\u8bfb\u548c\u4e0d\u53ef\u91cd\u590d\u8bfb,\u4f46\u4ecd\u7136\u53ef\u80fd\u53d1\u751f\u5e7b\u8bfb,\u53ef\u80fd\u53d1\u751f\u5e7b\u8bfb\u5c31\u8868\u793a\u53ef\u91cd\u590d\u8bfb\u8fd9\u4e2a\u9694\u79bb\u7ea7\u522b\u9632\u4e0d\u4f4f\u5e7b\u8bfb\u5417?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u4e0d\u7ba1\u4ece\u6570\u636e\u5e93\u65b9\u9762\u7684\u6559\u79d1\u4e66\u8fd8\u662f\u4e00\u4e9b\u7f51\u7edc\u6559\u7a0b\u4e0a,\u7ecf\u5e38\u770b\u5230RR\u7ea7\u522b\u662f\u53ef\u4ee5\u91cd\u590d\u8bfb\u7684,\u4f46\u662f\u65e0\u6cd5\u89e3\u51b3\u5e7b\u8bfb,\u53ea\u6709\u53ef\u4e32\u884c\u5316(Serializable)\u624d\u80fd\u89e3\u51b3\u5e7b\u8bfb,\u8fd9\u4e2a\u8bf4\u6cd5\u662f\u5426\u6b63\u786e\u5462?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u8fd9\u7bc7\u6587\u7ae0\u4e2d,\u6211\u5c06\u91cd\u70b9\u56f4\u7ed5MySQL\u4e2d<strong>\u300c\u53ef\u91cd\u590d\u8bfb\uff08Repeatable read\uff09\u80fd\u9632\u4f4f\u5e7b\u8bfb\u5417?\u300d<\/strong>\n\u8fd9\u4e00\u95ee\u9898\u5c55\u5f00\u8ba8\u8bba,\u76f8\u4fe1\u770b\u5b8c\u8fd9\u7bc7\u6587\u7ae0\u540e,\u4f60\u4e00\u5b9a\u4f1a\u5bf9\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u6709\u65b0\u7684\u8ba4\u8bc6\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u4eec\u7684\u6570\u636e\u5e93\u4e2d\u6709\u5982\u4e0b\u7ed3\u6784\u548c\u6570\u636e\u7684Users\u8868,\u4e0b\u6587\u4e2d\u6211\u4eec\u5c06\u5bf9\u8fd9\u5f20\u8868\u8fdb\u884c\u64cd\u4f5c\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/users.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<h2 class=\"wp-block-heading\">\u4ec0\u4e48\u662f\u5e7b\u8bfb?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u8bf4\u5e7b\u8bfb\u4e4b\u524d,\u6211\u4eec\u8981\u5148\u6765\u4e86\u89e3\u810f\u8bfb\u548c\u4e0d\u53ef\u91cd\u590d\u8bfb\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u810f\u8bfb<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5f53\u4e00\u4e2a\u4e8b\u52a1\u8bfb\u53d6\u5230\u53e6\u5916\u4e00\u4e2a\u4e8b\u52a1\u4fee\u6539\u4f46\u672a\u63d0\u4ea4\u7684\u6570\u636e\u65f6\uff0c\u5c31\u53ef\u80fd\u53d1\u751f\u810f\u8bfb\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/%E8%84%8F%E8%AF%BB.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u6211\u4eec\u7684\u4f8b\u5b50\u4e2d\uff0c\u4e8b\u52a12\u4fee\u6539\u4e86\u4e00\u884c\uff0c\u4f46\u662f\u6ca1\u6709\u63d0\u4ea4\uff0c\u4e8b\u52a11\u8bfb\u4e86\u8fd9\u4e2a\u6ca1\u6709\u63d0\u4ea4\u7684\u6570\u636e\u3002\u73b0\u5728\u5982\u679c\u4e8b\u52a12\u56de\u6eda\u4e86\u521a\u624d\u7684\u4fee\u6539\u6216\u8005\u505a\u4e86\u53e6\u5916\u7684\u4fee\u6539\u7684\u8bdd\uff0c\u4e8b\u52a11\u4e2d\u67e5\u5230\u7684\u6570\u636e\u5c31\u662f\u4e0d\u6b63\u786e\u7684\u4e86,\u6240\u4ee5\u8fd9\u6761\u6570\u636e\u5c31\u662f\u810f\u8bfb\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e0d\u53ef\u91cd\u590d\u8bfb<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u201c\u4e0d\u53ef\u91cd\u590d\u8bfb\u201d\u73b0\u8c61\u53d1\u751f\u5728\u5f53\u6267\u884cSELECT \u64cd\u4f5c\u65f6\u6ca1\u6709\u83b7\u5f97\u8bfb\u9501\u6216\u8005SELECT\u64cd\u4f5c\u6267\u884c\u5b8c\u540e\u9a6c\u4e0a\u91ca\u653e\u4e86\u8bfb\u9501\uff1b \u53e6\u5916\u4e00\u4e2a\u4e8b\u52a1\u5bf9\u6570\u636e\u8fdb\u884c\u4e86\u66f4\u65b0,\u8bfb\u5230\u4e86\u4e0d\u540c\u7684\u7ed3\u679c\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/%E4%B8%8D%E5%8F%AF%E9%87%8D%E5%A4%8D%E8%AF%BB.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u8fd9\u4e2a\u4f8b\u5b50\u4e2d\uff0c\u4e8b\u52a12\u63d0\u4ea4\u6210\u529f\uff0c\u56e0\u6b64\u4ed6\u5bf9id\u4e3a1\u7684\u884c\u7684\u4fee\u6539\u5c31\u5bf9\u5176\u4ed6\u4e8b\u52a1\u53ef\u89c1\u4e86\u3002\u5bfc\u81f4\u4e86\u4e8b\u52a11\u5728\u6b64\u524d\u8bfb\u7684age=1,\u7b2c\u4e8c\u6b21\u8bfb\u7684age=2,\u4e24\u6b21\u7ed3\u679c\u4e0d\u4e00\u81f4,\u8fd9\u5c31\u662f\u4e0d\u53ef\u91cd\u590d\u8bfb.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u5e7b\u8bfb<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u201c\u5e7b\u8bfb\u201d\u53c8\u53eb&#8221;\u5e7b\u8c61\u8bfb&#8221;,\u662f&#8221;\u4e0d\u53ef\u91cd\u590d\u8bfb&#8221;\u7684\u4e00\u79cd\u7279\u6b8a\u573a\u666f\uff1a\u5f53\u4e8b\u52a11\u4e24\u6b21\u6267\u884c&#8221;SELECT &#8230; WHERE&#8221;\u68c0\u7d22\u4e00\u5b9a\u8303\u56f4\u5185\u6570\u636e\u7684\u64cd\u4f5c\u4e2d\u95f4\uff0c\u4e8b\u52a12\u5728\u8fd9\u4e2a\u8868\u4e2d\u521b\u5efa\u4e86(\u5982 INSERT )\u4e86\u4e00\u884c\u65b0\u6570\u636e\uff0c\u8fd9\u6761\u65b0\u6570\u636e\u6b63\u597d\u6ee1\u8db3\u4e8b\u52a11\u7684\u201cWHERE\u201d\u5b50\u53e5\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/%E5%B9%BB%E8%AF%BB.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u5982\u56fe\u4e8b\u52a11\u6267\u884c\u4e86\u4e24\u904d\u540c\u6837\u7684\u67e5\u8be2\u8bed\u53e5,\u7b2c\u4e8c\u904d\u6bd4\u7b2c\u4e00\u904d\u591a\u51fa\u4e86\u4e00\u6761\u6570\u636e,\u8fd9\u5c31\u662f\u5e7b\u8bfb\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e09\u8005\u5230\u5e95\u4ec0\u4e48\u533a\u522b<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e09\u8005\u7684\u573a\u666f\u4ecb\u7ecd\u5b8c,\u4f46\u662f\u4e00\u5b9a\u4ecd\u7136\u6709\u5f88\u591a\u540c\u5b66\u641e\u4e0d\u6e05\u695a,\u5b83\u4eec\u5230\u5e95\u6709\u4ec0\u4e48\u533a\u522b,\u6211\u603b\u7ed3\u4e00\u4e0b\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u810f\u8bfb:\u6307\u8bfb\u5230\u4e86\u5176\u4ed6\u4e8b\u52a1\u672a\u63d0\u4ea4\u7684\u6570\u636e\u3002<\/li><li>\u4e0d\u53ef\u91cd\u590d\u8bfb: \u8bfb\u5230\u4e86\u5176\u4ed6\u4e8b\u52a1\u5df2\u63d0\u4ea4\u7684\u6570\u636e(update)\u3002<\/li><li>\u4e0d\u53ef\u91cd\u590d\u8bfb\u4e0e\u5e7b\u8bfb\u90fd\u662f\u8bfb\u5230\u5176\u4ed6\u4e8b\u52a1\u5df2\u63d0\u4ea4\u7684\u6570\u636e,\u4f46\u662f\u5b83\u4eec\u9488\u5bf9\u70b9\u4e0d\u540c\u3002<\/li><li>\u4e0d\u53ef\u91cd\u590d\u8bfb:update\u3002<\/li><li>\u5e7b\u8bfb:delete\uff0cinsert\u3002<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">MySQL\u4e2d\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">\u672a\u63d0\u4ea4\u8bfb<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u672a\u63d0\u4ea4\u8bfb\uff08READ UNCOMMITTED\uff09\u662f\u6700\u4f4e\u7684\u9694\u79bb\u7ea7\u522b,\u5728\u8fd9\u79cd\u9694\u79bb\u7ea7\u522b\u4e0b,\u5982\u679c\u4e00\u4e2a\u4e8b\u52a1\u5df2\u7ecf\u5f00\u59cb\u5199\u6570\u636e\uff0c\u5219\u53e6\u5916\u4e00\u4e2a\u4e8b\u52a1\u5219\u4e0d\u5141\u8bb8\u540c\u65f6\u8fdb\u884c\u5199\u64cd\u4f5c\uff0c\u4f46\u5141\u8bb8\u5176\u4ed6\u4e8b\u52a1\u8bfb\u6b64\u884c\u6570\u636e.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u628a\u810f\u8bfb\u7684\u56fe\u62ff\u6765\u5206\u6790\u5206\u6790,\u56e0\u4e3a\u4e8b\u52a12\u66f4\u65b0id=1\u7684\u6570\u636e\u540e,\u4ecd\u7136\u5141\u8bb8\u4e8b\u52a11\u8bfb\u53d6\u8be5\u6761\u6570\u636e,\u6240\u4ee5\u4e8b\u52a11\u7b2c\u4e8c\u6b21\u6267\u884c\u67e5\u8be2,\u8bfb\u5230\u4e86\u4e8b\u52a12\u66f4\u65b0\u7684\u7ed3\u679c,\u4ea7\u751f\u4e86\u810f\u8bfb\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/%E8%84%8F%E8%AF%BB.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">\u5df2\u63d0\u4ea4\u8bfb<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u7531\u4e8eMySQL\u7684InnoDB\u9ed8\u8ba4\u662f\u4f7f\u7528\u7684RR\u7ea7\u522b\uff0c\u6240\u4ee5\u6211\u4eec\u5148\u8981\u5c06\u8be5session\u5f00\u542f\u6210RC\u7ea7\u522b\uff0c\u5e76\u4e14\u8bbe\u7f6ebinlog\u7684\u6a21\u5f0f\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>SET session transaction isolation level read committed;\nSET SESSION binlog_format = 'ROW';--\uff08\u6216\u8005\u662fMIXED\uff09<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u540c\u6837,\u6211\u4eec\u6765\u5206\u6790\u810f\u8bfb,\u4e8b\u52a12\u66f4\u65b0id=1\u7684\u6570\u636e\u540e,\u5728\u63d0\u4ea4\u524d,\u4f1a\u5bf9\u8be5\u5bf9\u8c61\u5199\u9501,\u6240\u4ee5\u4e8b\u52a11\u8bfb\u53d6id=1\u7684\u6570\u636e\u65f6,\u4f1a\u4e00\u76f4\u7b49\u5f85\u4e8b\u52a12\u7ed3\u675f,\u5904\u4e8e\u963b\u585e\u72b6\u6001,\u907f\u514d\u4e86\u4ea7\u751f\u810f\u8bfb\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u5df2\u63d0\u4ea4\u8bfb\uff08READ COMMITTED\uff09\u7ea7\u522b\u4e2d\uff0c\u8bfb\u53d6\u6570\u636e\u7684\u4e8b\u52a1\u5141\u8bb8\u5176\u4ed6\u4e8b\u52a1\u7ee7\u7eed\u8bbf\u95ee\u8be5\u884c\u6570\u636e\uff0c\u4f46\u662f\u672a\u63d0\u4ea4\u7684\u5199\u4e8b\u52a1\u5c06\u4f1a\u7981\u6b62\u5176\u4ed6\u4e8b\u52a1\u8bbf\u95ee\u8be5\u884c,\u4f1a\u5bf9\u8be5\u5199\u9501\u4e00\u76f4\u4fdd\u6301\u76f4\u5230\u5230\u4e8b\u52a1\u63d0\u4ea4\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/%E8%84%8F%E8%AF%BB.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u540c\u6837,\u6765\u5206\u6790\u4e0d\u53ef\u91cd\u590d\u8bfb,\u4e8b\u52a11\u8bfb\u53d6id=1\u7684\u6570\u636e\u540e\u5e76\u6ca1\u6709\u9501\u4f4f\u8be5\u6570\u636e,\u6240\u4ee5\u4e8b\u52a12\u80fd\u5bf9\u8fd9\u6761\u6570\u636e\u8fdb\u884c\u66f4\u65b0,\u4e8b\u52a12\u5bf9\u66f4\u65b0\u5e76\u63d0\u4ea4\u540e,\u8be5\u6570\u636e\u7acb\u5373\u751f\u6548,\u6240\u4ee5\u4e8b\u52a11\u518d\u6b21\u6267\u884c\u540c\u6837\u7684\u67e5\u8be2,\u67e5\u8be2\u5230\u7684\u7ed3\u679c\u4fbf\u4e0e\u7b2c\u4e00\u6b21\u67e5\u5230\u7684\u4e0d\u540c,\u6240\u4ee5\u5df2\u63d0\u4ea4\u8bfb\u9632\u4e0d\u4e86\u4e0d\u53ef\u91cd\u590d\u8bfb\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/%E4%B8%8D%E5%8F%AF%E9%87%8D%E5%A4%8D%E8%AF%BB.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">\u53ef\u91cd\u590d\u8bfb<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u53ef\u91cd\u590d\u8bfb\uff08REPEATABLE READS\uff09\u662f\u4ecb\u4e8e\u5df2\u63d0\u4ea4\u8bfb\u548c\u53ef\u4e32\u884c\u5316\u4e4b\u95f4\u7684\u4e00\u79cd\u9694\u79bb\u7ea7\u522b(\u5e9f\u8bdd&#x1f605;),\u5b83\u662fInnoDb\u7684\u9ed8\u8ba4\u9694\u79bb\u7ea7\u522b,\u5b83\u662f\u6211\u8fd9\u7bc7\u6587\u7ae0\u7684\u91cd\u70b9\u8ba8\u8bba\u5bf9\u8c61,\u6240\u4ee5\u5728\u8fd9\u91cc\u6211\u5148\u5356\u4e2a\u5173\u5b50,\u540e\u9762\u6211\u4f1a\u8be6\u7ec6\u4ecb\u7ecd.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u53ef\u4e32\u884c\u5316<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u53ef\u4e32\u884c\u5316\uff08Serializable \uff09\u662f\u9ad8\u7684\u9694\u79bb\u7ea7\u522b,\u5b83\u6c42\u5728\u9009\u5b9a\u5bf9\u8c61\u4e0a\u7684\u8bfb\u9501\u548c\u5199\u9501\u4fdd\u6301\u76f4\u5230\u4e8b\u52a1\u7ed3\u675f\u540e\u624d\u80fd\u91ca\u653e,\u6240\u4ee5\u80fd\u9632\u4f4f\u4e0a\u8bc9\u6240\u6709\u95ee\u9898,\u4f46\u56e0\u4e3a\u662f\u4e32\u884c\u5316\u7684,\u6240\u4ee5\u6548\u7387\u8f83\u4f4e.<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/%E8%AF%B4%E6%AD%A3%E4%BA%8B.jpg\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e86\u89e3\u5230\u4e86\u4e0a\u8bc9\u7684\u4e00\u4e9b\u80cc\u666f\u77e5\u8bc6\u540e,\u4e0b\u9762\u6b63\u5f0f\u5f00\u59cb\u6211\u4eec\u7684\u8bae\u9898.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u53ef\u91cd\u590d\u8bfb\uff08Repeatable read\uff09\u80fd\u9632\u4f4f\u5e7b\u8bfb\u5417?<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u53ef\u91cd\u590d\u8bfb<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u8bb2\u53ef\u91cd\u590d\u8bfb\u4e4b\u524d,\u6211\u4eec\u5148\u5728mysql\u7684InnoDB\u4e0b\u505a\u4e0b\u9762\u7684\u5b9e\u9a8c\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/RR.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u53ef\u4ee5\u770b\u5230,\u4e8b\u52a1A\u65e2\u6ca1\u6709\u8bfb\u5230\u4e8b\u52a1B\u66f4\u65b0\u7684\u6570\u636e,\u4e5f\u6ca1\u6709\u8bfb\u5230\u4e8b\u52a1C\u6dfb\u52a0\u7684\u6570\u636e,\u6240\u4ee5\u5728\u8fd9\u4e2a\u573a\u666f\u4e0b,\u5b83\u65e2\u9632\u4f4f\u4e86\u4e0d\u53ef\u91cd\u590d\u8bfb,\u4e5f\u9632\u4f4f\u4e86\u5e7b\u8bfb.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5230\u6b64\u4e3a\u6b62,\u76f8\u4fe1\u5927\u5bb6\u5df2\u7ecf\u77e5\u9053\u7b54\u6848\u4e86,\u8fd9\u662f\u600e\u4e48\u505a\u5230\u7684\u5462?<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u60b2\u89c2\u9501\u4e0e\u4e50\u89c2\u9501<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u4eec\u524d\u9762\u8bf4\u7684\u5728\u5bf9\u8c61\u4e0a\u52a0\u9501,\u662f\u4e00\u79cd\u60b2\u89c2\u9501\u673a\u5236,\u6709\u5f88\u591a\u6587\u7ae0\u8bf4\u53ef\u91cd\u590d\u8bfb\u7684\u9694\u79bb\u7ea7\u522b\u9632\u4e0d\u4e86\u5e7b\u8bfb, \u662f\u8ba4\u4e3a\u53ef\u91cd\u590d\u8bfb\u4f1a\u5bf9\u8bfb\u7684\u884c\u52a0\u9501,\u5bfc\u81f4\u4ed6\u4e8b\u52a1\u4fee\u6539\u4e0d\u4e86\u8fd9\u6761\u6570\u636e,\u76f4\u5230\u4e8b\u52a1\u7ed3\u675f,\u4f46\u662f\u8fd9\u79cd\u65b9\u6848\u53ea\u80fd\u9501\u4f4f\u6570\u636e\u884c,\u5982\u679c\u6709\u65b0\u7684\u6570\u636e\u8fdb\u6765,\u662f\u963b\u6b62\u4e0d\u4e86\u7684,\u6240\u4ee5\u4f1a\u4ea7\u751f\u5e7b\u8bfb.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u53ef\u662fMySQL\u3001ORACLE\u3001PostgreSQL\u7b49\u5df2\u7ecf\u662f\u975e\u5e38\u6210\u719f\u7684\u6570\u636e\u5e93\u4e86,\u600e\u4e48\u4f1a\u5355\u7eaf\u5730\u91c7\u7528\u8fd9\u79cd\u5982\u6b64\u5f71\u54cd\u6027\u80fd\u7684\u65b9\u6848\u5462?<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/mysql.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u6765\u4ecb\u7ecd\u4e00\u4e0b\u60b2\u89c2\u9501\u548c\u4e50\u89c2\u9501\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u60b2\u89c2\u9501<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u6b63\u5982\u5176\u540d\uff0c\u5b83\u6307\u7684\u662f\u5bf9\u6570\u636e\u88ab\u5916\u754c\uff08\u5305\u62ec\u672c\u7cfb\u7edf\u5f53\u524d\u7684\u5176\u4ed6\u4e8b\u52a1\uff0c\u4ee5\u53ca\u6765\u81ea\u5916\u90e8\u7cfb\u7edf\u7684\u4e8b\u52a1\u5904\u7406\uff09\u4fee\u6539\u6301\u4fdd\u5b88\u6001\u5ea6\uff0c\u56e0\u6b64\uff0c\u5728\u6574\u4e2a\u6570\u636e\u5904\u7406\u8fc7\u7a0b\u4e2d\uff0c\u5c06\u6570\u636e\u5904\u4e8e\u9501\u5b9a\u72b6\u6001\u3002\u8bfb\u53d6\u6570\u636e\u65f6\u7ed9\u52a0\u9501\uff0c\u5176\u5b83\u4e8b\u52a1\u65e0\u6cd5\u4fee\u6539\u8fd9\u4e9b\u6570\u636e\u3002\u4fee\u6539\u5220\u9664\u6570\u636e\u65f6\u4e5f\u8981\u52a0\u9501\uff0c\u5176\u5b83\u4e8b\u52a1\u65e0\u6cd5\u8bfb\u53d6\u8fd9\u4e9b\u6570\u636e\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e50\u89c2\u9501<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u76f8\u5bf9\u60b2\u89c2\u9501\u800c\u8a00\uff0c\u4e50\u89c2\u9501\u673a\u5236\u91c7\u53d6\u4e86\u66f4\u52a0\u5bbd\u677e\u7684\u52a0\u9501\u673a\u5236\u3002\u60b2\u89c2\u9501\u5927\u591a\u6570\u60c5\u51b5\u4e0b\u4f9d\u9760\u6570\u636e\u5e93\u7684\u9501\u673a\u5236\u5b9e\u73b0\uff0c\u4ee5\u4fdd\u8bc1\u64cd\u4f5c\u6700\u5927\u7a0b\u5ea6\u7684\u72ec\u5360\u6027\u3002\u4f46\u968f\u4e4b\u800c\u6765\u7684\u5c31\u662f\u6570\u636e\u5e93\u6027\u80fd\u7684\u5927\u91cf\u5f00\u9500\uff0c\u7279\u522b\u662f\u5bf9\u957f\u4e8b\u52a1\u800c\u8a00\uff0c\u8fd9\u6837\u7684\u5f00\u9500\u5f80\u5f80\u65e0\u6cd5\u627f\u53d7\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u800c\u4e50\u89c2\u9501\u673a\u5236\u5728\u4e00\u5b9a\u7a0b\u5ea6\u4e0a\u89e3\u51b3\u4e86\u8fd9\u4e2a\u95ee\u9898\u3002\u4e50\u89c2\u9501\uff0c\u5927\u591a\u662f\u57fa\u4e8e\u6570\u636e\u7248\u672c\uff08 Version \uff09\u8bb0\u5f55\u673a\u5236\u5b9e\u73b0\u3002\u4f55\u8c13\u6570\u636e\u7248\u672c\uff1f\u5373\u4e3a\u6570\u636e\u589e\u52a0\u4e00\u4e2a\u7248\u672c\u6807\u8bc6\uff0c\u5728\u57fa\u4e8e\u6570\u636e\u5e93\u8868\u7684\u7248\u672c\u89e3\u51b3\u65b9\u6848\u4e2d\uff0c\u4e00\u822c\u662f\u901a\u8fc7\u4e3a\u6570\u636e\u5e93\u8868\u589e\u52a0\u4e00\u4e2a \u201cversion\u201d \u5b57\u6bb5\u6765\u5b9e\u73b0\u3002\u8bfb\u53d6\u51fa\u6570\u636e\u65f6\uff0c\u5c06\u6b64\u7248\u672c\u53f7\u4e00\u540c\u8bfb\u51fa\uff0c\u4e4b\u540e\u66f4\u65b0\u65f6\uff0c\u5bf9\u6b64\u7248\u672c\u53f7\u52a0\u4e00\u3002\u6b64\u65f6\uff0c\u5c06\u63d0\u4ea4\u6570\u636e\u7684\u7248\u672c\u6570\u636e\u4e0e\u6570\u636e\u5e93\u8868\u5bf9\u5e94\u8bb0\u5f55\u7684\u5f53\u524d\u7248\u672c\u4fe1\u606f\u8fdb\u884c\u6bd4\u5bf9\uff0c\u5982\u679c\u63d0\u4ea4\u7684\u6570\u636e\u7248\u672c\u53f7\u5927\u4e8e\u6570\u636e\u5e93\u8868\u5f53\u524d\u7248\u672c\u53f7\uff0c\u5219\u4e88\u4ee5\u66f4\u65b0\uff0c\u5426\u5219\u8ba4\u4e3a\u662f\u8fc7\u671f\u6570\u636e\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">MySQL\u3001ORACLE\u3001PostgreSQL\u7b49\u90fd\u662f\u4f7f\u7528\u4e86\u4ee5\u4e50\u89c2\u9501\u4e3a\u7406\u8bba\u57fa\u7840\u7684MVCC\uff08\u591a\u7248\u672c\u5e76\u53d1\u63a7\u5236\uff09\u6765\u907f\u514d\u4e0d\u53ef\u91cd\u590d\u8bfb\u548c\u5e7b\u8bfb,MVCC\u7684\u5b9e\u73b0\u6ca1\u6709\u56fa\u5b9a\u7684\u89c4\u8303\uff0c\u6bcf\u4e2a\u6570\u636e\u5e93\u90fd\u4f1a\u6709\u4e0d\u540c\u7684\u5b9e\u73b0\u65b9\u5f0f\uff0c\u8fd9\u91cc\u8ba8\u8bba\u7684\u662fInnoDB\u7684MVCC\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">MVCC(\u591a\u7248\u672c\u5e76\u53d1\u63a7\u5236)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728InnoDB\u4e2d\uff0c\u4f1a\u5728\u6bcf\u884c\u6570\u636e\u540e\u6dfb\u52a0\u4e24\u4e2a\u989d\u5916\u7684\u9690\u85cf\u7684\u503c\u6765\u5b9e\u73b0MVCC\uff0c\u8fd9\u4e24\u4e2a\u503c\u4e00\u4e2a\u8bb0\u5f55\u8fd9\u884c\u6570\u636e\u4f55\u65f6\u88ab\u521b\u5efa\uff0c\u53e6\u5916\u4e00\u4e2a\u8bb0\u5f55\u8fd9\u884c\u6570\u636e\u4f55\u65f6\u8fc7\u671f\uff08\u6216\u8005\u88ab\u5220\u9664\uff09\u3002 \u5728\u5b9e\u9645\u64cd\u4f5c\u4e2d\uff0c\u5b58\u50a8\u7684\u5e76\u4e0d\u662f\u65f6\u95f4\uff0c\u800c\u662f\u4e8b\u52a1\u7684\u7248\u672c\u53f7\uff0c\u6bcf\u5f00\u542f\u4e00\u4e2a\u65b0\u4e8b\u52a1\uff0c\u4e8b\u52a1\u7684\u7248\u672c\u53f7\u5c31\u4f1a\u9012\u589e\u3002 \u5728\u53ef\u91cd\u8bfbRepeatable reads\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u4e0b\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>SELECT\u65f6\uff0c\u8bfb\u53d6\u521b\u5efa\u7248\u672c\u53f7&lt;=\u5f53\u524d\u4e8b\u52a1\u7248\u672c\u53f7\uff0c\u5220\u9664\u7248\u672c\u53f7\u4e3a\u7a7a\u6216&gt;\u5f53\u524d\u4e8b\u52a1\u7248\u672c\u53f7\u3002<\/li><li>INSERT\u65f6\uff0c\u4fdd\u5b58\u5f53\u524d\u4e8b\u52a1\u7248\u672c\u53f7\u4e3a\u884c\u7684\u521b\u5efa\u7248\u672c\u53f7<\/li><li>DELETE\u65f6\uff0c\u4fdd\u5b58\u5f53\u524d\u4e8b\u52a1\u7248\u672c\u53f7\u4e3a\u884c\u7684\u5220\u9664\u7248\u672c\u53f7<\/li><li>UPDATE\u65f6\uff0c\u63d2\u5165\u4e00\u6761\u65b0\u7eaa\u5f55\uff0c\u4fdd\u5b58\u5f53\u524d\u4e8b\u52a1\u7248\u672c\u53f7\u4e3a\u884c\u521b\u5efa\u7248\u672c\u53f7\uff0c\u540c\u65f6\u4fdd\u5b58\u5f53\u524d\u4e8b\u52a1\u7248\u672c\u53f7\u5230\u539f\u6765\u5220\u9664\u7684\u884c<\/li><\/ul>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/mvcc.png\" alt=\"\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u901a\u8fc7MVCC,\u867d\u7136\u6bcf\u884c\u8bb0\u5f55\u90fd\u8981\u989d\u5916\u7684\u5b58\u50a8\u7a7a\u95f4\u6765\u8bb0\u5f55version,\u9700\u8981\u66f4\u591a\u7684\u884c\u68c0\u67e5\u5de5\u4f5c\u4ee5\u53ca\u4e00\u4e9b\u989d\u5916\u7684\u7ef4\u62a4\u5de5\u4f5c,\u4f46\u53ef\u4ee5\u51cf\u5c11\u9501\u7684\u4f7f\u7528,\u5927\u591a\u8bfb\u64cd\u4f5c\u90fd\u4e0d\u7528\u52a0\u9501,\u8bfb\u53d6\u6570\u636e\u64cd\u4f5c\u7b80\u5355,\u6027\u80fd\u597d.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7ec6\u5fc3\u7684\u540c\u5b66\u5e94\u8be5\u4e5f\u770b\u5230\u4e86,\u901a\u8fc7MVCC\u8bfb\u53d6\u51fa\u6765\u7684\u6570\u636e\u5176\u5b9e\u662f\u5386\u53f2\u6570\u636e,\u800c\u4e0d\u662f\u6700\u65b0\u6570\u636e,\u8fd9\u5728\u4e00\u4e9b\u5bf9\u4e8e\u6570\u636e\u65f6\u6548\u7279\u522b\u654f\u611f\u7684\u4e1a\u52a1\u4e2d,\u5f88\u53ef\u80fd\u51fa\u95ee\u9898,\u8fd9\u4e5f\u662fMVCC\u7684\u77ed\u677f\u4e4b\u5904,\u6709\u529e\u6cd5\u89e3\u51b3\u5417? \u5f53\u7136\u6709.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">MCVV\u8fd9\u79cd\u8bfb\u53d6\u5386\u53f2\u6570\u636e\u7684\u65b9\u5f0f\u79f0\u4e3a\u5feb\u7167\u8bfb(snapshot read),\u800c\u8bfb\u53d6\u6570\u636e\u5e93\u5f53\u524d\u7248\u672c\u6570\u636e\u7684\u65b9\u5f0f,\u53eb\u5f53\u524d\u8bfb(current read).<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u5feb\u7167\u8bfb<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u4eec\u5e73\u65f6\u53ea\u7528\u4f7f\u7528select\u5c31\u662f\u5feb\u7167\u8bfb,\u8fd9\u6837\u53ef\u4ee5\u51cf\u5c11\u52a0\u9501\u6240\u5e26\u6765\u7684\u5f00\u9500\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>select\u00a0*\u00a0from\u00a0table\u00a0....<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u5f53\u524d\u8bfb<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5bf9\u4e8e\u4f1a\u5bf9\u6570\u636e\u4fee\u6539\u7684\u64cd\u4f5c(update\u3001insert\u3001delete)\u90fd\u662f\u91c7\u7528\u5f53\u524d\u8bfb\u7684\u6a21\u5f0f\u3002\u5728\u6267\u884c\u8fd9\u51e0\u4e2a\u64cd\u4f5c\u65f6\u4f1a\u8bfb\u53d6\u6700\u65b0\u7684\u8bb0\u5f55\uff0c\u5373\u4f7f\u662f\u522b\u7684\u4e8b\u52a1\u63d0\u4ea4\u7684\u6570\u636e\u4e5f\u53ef\u4ee5\u67e5\u8be2\u5230\u3002\u5047\u8bbe\u8981update\u4e00\u6761\u8bb0\u5f55\uff0c\u4f46\u662f\u5728\u53e6\u4e00\u4e2a\u4e8b\u52a1\u4e2d\u5df2\u7ecfdelete\u6389\u8fd9\u6761\u6570\u636e\u5e76\u4e14commit\u4e86\uff0c\u5982\u679cupdate\u5c31\u4f1a\u4ea7\u751f\u51b2\u7a81\uff0c\u6240\u4ee5\u5728update\u7684\u65f6\u5019\u9700\u8981\u77e5\u9053\u6700\u65b0\u7684\u6570\u636e\u3002\u8bfb\u53d6\u7684\u662f\u6700\u65b0\u7684\u6570\u636e\uff0c\u9700\u8981\u52a0\u9501\u3002\u4ee5\u4e0b\u7b2c\u4e00\u4e2a\u8bed\u53e5\u9700\u8981\u52a0\u5171\u4eab\u9501\uff0c\u5176\u5b83\u90fd\u9700\u8981\u52a0\u6392\u5b83\u9501\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>select\u00a0*\u00a0from\u00a0table\u00a0where\u00a0?\u00a0lock\u00a0in\u00a0share\u00a0mode;\u00a0\nselect\u00a0*\u00a0from\u00a0table\u00a0where\u00a0?\u00a0for\u00a0update;\u00a0\ninsert;\u00a0\nupdate;\u00a0\ndelete;<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u4eec\u518d\u5229\u7528\u5f53\u524d\u8bfb\u6765\u505a\u8bd5\u9a8c\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/nextkeytest.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">\u53ef\u4ee5\u770b\u5230\u5728\u8bfb\u63d0\u4ea4\u7684\u9694\u79bb\u7ea7\u522b\u4e2d,\u4e8b\u52a11\u4fee\u6539\u4e86\u6240\u6709class_id=1\u7684\u6570\u636e,\u5f53\u65f6\u5f53\u4e8b\u52a12 insert\u540e,\u4e8b\u52a1A\u83ab\u540d\u5947\u5999\u5730\u591a\u4e86\u4e00\u884cclass_id=1\u7684\u6570\u636e,\u800c\u4e14\u6ca1\u6709\u88ab\u4e4b\u524d\u7684update\u6240\u4fee\u6539,\u4ea7\u751f\u4e86\u8bfb\u63d0\u4ea4\u4e0b\u7684\u7684\u5e7b\u8bfb.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u800c\u5728\u53ef\u91cd\u590d\u5ea6\u7684\u9694\u79bb\u7ea7\u522b\u4e0b,\u60c5\u51b5\u5c31\u5b8c\u5168\u4e0d\u540c\u4e86.\u4e8b\u52a11\u5728update\u540e,\u5bf9\u8be5\u6570\u636e\u52a0\u9501,\u4e8b\u52a1B\u65e0\u6cd5\u63d2\u5165\u65b0\u7684\u6570\u636e,\u8fd9\u6837\u4e8b\u52a1A\u5728update\u524d\u540e\u6570\u636e\u4fdd\u6301\u4e00\u81f4,\u907f\u514d\u4e86\u5e7b\u8bfb,\u53ef\u4ee5\u660e\u786e\u7684\u662f,update\u9501\u7684\u80af\u5b9a\u4e0d\u53ea\u662f\u5df2\u67e5\u8be2\u5230\u7684\u51e0\u6761\u6570\u636e,\u56e0\u4e3a\u8fd9\u6837\u65e0\u6cd5\u963b\u6b62insert,\u6709\u540c\u5b66\u4f1a\u8bf4,\u90a3\u5c31\u662f\u9501\u4f4f\u4e86\u6574\u5f20\u8868\u5457.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd8\u662f\u90a3\u53e5\u8bdd, Mysql\u5df2\u7ecf\u662f\u4e2a\u6210\u719f\u7684\u6570\u636e\u5e93\u4e86,\u600e\u4e48\u4f1a\u91c7\u7528\u5982\u6b64\u4f4e\u6548\u7684\u65b9\u6cd5\u5462? \u5176\u5b9e\u8fd9\u91cc\u7684\u9501,\u662f\u901a\u8fc7next-key\u9501\u5b9e\u73b0\u7684.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Next-Key\u9501#\n\u5728Users\u8fd9\u5f20\u8868\u91cc\u9762,class_id\u662f\u4e2a\u975e\u805a\u7c07\u7d22\u5f15,\u6570\u636e\u5e93\u4f1a\u901a\u8fc7B+\u6811\u7ef4\u62a4\u4e00\u4e2a\u975e\u805a\u7c07\u7d22\u5f15\u4e0e\u4e3b\u952e\u7684\u5173\u7cfb,\u7b80\u5355\u6765\u8bf4,\u6211\u4eec\u5148\u901a\u8fc7class_id=1\u627e\u5230\u8fd9\u4e2a\u7d22\u5f15\u6240\u5bf9\u5e94\u6240\u6709\u8282\u70b9,\u8fd9\u4e9b\u8282\u70b9\u5b58\u50a8\u7740\u5bf9\u5e94\u6570\u636e\u7684\u4e3b\u952e\u4fe1\u606f,\u5373id=1,\u6211\u4eec\u518d\u901a\u8fc7\u4e3b\u952eid=1\u627e\u5230\u6211\u4eec\u8981\u7684\u6570\u636e,\u8fd9\u4e2a\u8fc7\u7a0b\u79f0\u4e3a\u56de\u8868\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u672c\u60f3\u7528\u6211\u4eec\u6587\u7ae0\u4e2d\u7684\u4f8b\u5b50\u6765\u753b\u4e00\u4e2aB+\u6811,\u53ef\u662f\u753b\u5f97\u592a\u4e11\u4e86,\u4e3a\u4e86\u907f\u514d\u62c9\u4f4e\u6b64\u504f\u6587\u7ae0B\u683c.\u6240\u4ee5\u6211\u60f3\u5f15\u7528\u4e0a\u9762\u90a3\u8fb9\u6587\u7ae0\u4e2d\u4f5c\u8005\u753b\u7684B+\u6811\u6765\u89e3\u91caNext-key\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5047\u8bbe\u6211\u4eec\u4e0a\u9762\u7528\u5230\u7684User\u8868\u9700\u8981\u5bf9Name\u5efa\u7acb\u975e\u805a\u7c07\u7d22\u5f15,\u662f\u600e\u4e48\u5b9e\u73b0\u7684\u5462\uff1f\u6211\u4eec\u770b\u4e0b\u56fe\uff1a<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/btree.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">B+\u6811\u7684\u7279\u70b9\u662f\u6240\u6709\u6570\u636e\u90fd\u5b58\u50a8\u5728\u53f6\u5b50\u8282\u70b9\u4e0a,\u4ee5\u975e\u805a\u7c07\u7d22\u5f15\u7684\u79e6\u5bff\u751f\u4e3a\u4f8b,\u5728\u79e6\u5bff\u751f\u7684\u53f3\u53f6\u5b50\u8282\u70b9\u5b58\u50a8\u7740\u6240\u6709\u79e6\u5bff\u751f\u5bf9\u5e94\u7684Id,\u5373\u56fe\u4e2d\u768434,\u5728\u6211\u4eec\u5bf9\u8fd9\u6761\u6570\u636e\u505a\u4e86\u5f53\u524d\u8bfb\u540e,\u5c31\u4f1a\u5bf9\u8fd9\u6761\u6570\u636e\u52a0\u884c\u9501,\u5bf9\u4e8e\u884c\u9501\u5f88\u597d\u7406\u89e3,\u80fd\u591f\u9632\u6b62\u5176\u4ed6\u4e8b\u52a1\u5bf9\u5176\u8fdb\u884cupdate\u6216delete,\u4f46\u4e3a\u4ec0\u4e48\u8981\u52a0GAP\u9501\u5462?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd8\u662f\u90a3\u53e5\u8bdd,B+\u6811\u7684\u6240\u6709\u6570\u636e\u5b58\u50a8\u5728\u53f6\u5b50\u8282\u70b9\u4e0a,\u5f53\u6709\u4e00\u4e2a\u65b0\u7684\u53eb\u79e6\u5bff\u751f\u7684\u6570\u636e\u8fdb\u6765,\u4e00\u5b9a\u662f\u6392\u5728\u5728\u8fd9\u6761id=34\u7684\u6570\u636e\u524d\u9762\u6216\u8005\u540e\u9762\u7684,\u6211\u4eec\u5982\u679c\u5bf9\u524d\u540e\u8fd9\u4e2a\u8303\u56f4\u8fdb\u884c\u52a0\u9501\u4e86,\u90a3\u5f53\u7136\u65b0\u7684\u79e6\u5bff\u751f\u5c31\u63d2\u4e0d\u8fdb\u6765\u4e86.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u90a3\u5982\u679c\u6709\u4e00\u4e2a\u65b0\u7684\u8303\u7edf\u8981\u63d2\u8fdb\u884c\u5462? \u56e0\u4e3a\u8303\u7edf\u7684\u524d\u540e\u5e76\u6ca1\u6709\u88ab\u9501\u4f4f,\u662f\u80fd\u6210\u529f\u63d2\u5165\u7684,\u8fd9\u6837\u5c31\u6781\u5927\u5730\u63d0\u9ad8\u4e86\u6570\u636e\u5e93\u7684\u5e76\u53d1\u80fd\u529b.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u9a6c\u5931\u524d\u8e44<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0a\u6587\u4e2d\u8bf4\u4e86\u53ef\u91cd\u590d\u8bfb\u80fd\u9632\u4e0d\u53ef\u91cd\u590d\u8bfb,\u8fd8\u80fd\u9632\u5e7b\u8bfb,\u5b83\u80fd\u9632\u4f4f\u6240\u6709\u7684\u5e7b\u8bfb\u5417?\u5f53\u7136\u4e0d\u662f,\u4e5f\u6709\u9a6c\u5931\u524d\u8e44\u7684\u65f6\u5019.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6bd4\u5982\u5982\u4e0b\u7684\u4f8b\u5b50:<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter\"><img decoding=\"async\" src=\"https:\/\/g.ioiox.com\/https:\/\/raw.githubusercontent.com\/liuzhenyulive\/GitDisk\/blogs\/resource\/PhantomRead\/specialcase.png\" alt=\"\" \/><\/figure><\/div>\n\n\n\n<ol class=\"wp-block-list\"><li>a\u4e8b\u52a1\u5148select\uff0cb\u4e8b\u52a1insert\u786e\u5b9e\u4f1a\u52a0\u4e00\u4e2agap\u9501\uff0c\u4f46\u662f\u5982\u679cb\u4e8b\u52a1commit\uff0c\u8fd9\u4e2agap\u9501\u5c31\u4f1a\u91ca\u653e\uff08\u91ca\u653e\u540ea\u4e8b\u52a1\u53ef\u4ee5\u968f\u610f\u64cd\u4f5c\uff09\uff0c<\/li><li>a\u4e8b\u52a1\u518dselect\u51fa\u6765\u7684\u7ed3\u679c\u5728MVCC\u4e0b\u8fd8\u548c\u7b2c\u4e00\u6b21select\u4e00\u6837\uff0c<\/li><li>\u63a5\u7740a\u4e8b\u52a1\u4e0d\u52a0\u6761\u4ef6\u5730update\uff0c\u8fd9\u4e2aupdate\u4f1a\u4f5c\u7528\u5728\u6240\u6709\u884c\u4e0a\uff08\u5305\u62ecb\u4e8b\u52a1\u65b0\u52a0\u7684\uff09\uff0c<\/li><li>a\u4e8b\u52a1\u518d\u6b21select\u5c31\u4f1a\u51fa\u73b0b\u4e8b\u52a1\u4e2d\u7684\u65b0\u884c\uff0c\u5e76\u4e14\u8fd9\u4e2a\u65b0\u884c\u5df2\u7ecf\u88abupdate\u4fee\u6539\u4e86.<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">Mysql\u5b98\u65b9\u7ed9\u51fa\u7684\u5e7b\u8bfb\u89e3\u91ca\u662f\uff1a\u53ea\u8981\u5728\u4e00\u4e2a\u4e8b\u52a1\u4e2d\uff0c\u7b2c\u4e8c\u6b21select\u591a\u51fa\u4e86row\u5c31\u7b97\u5e7b\u8bfb, \u6240\u4ee5\u8fd9\u4e2a\u573a\u666f\u4e0b,\u7b97\u51fa\u73b0\u5e7b\u8bfb\u4e86\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u90a3\u4e48\u6587\u7ae0\u6700\u540e\u7559\u4e2a\u95ee\u9898\uff0c\u4f60\u77e5\u9053\u4e3a\u4ec0\u4e48\u4e0a\u8bc9\u4f8b\u5b50\u4f1a\u51fa\u73b0\u5e7b\u8bfb\u5417\uff1f\u6b22\u8fce\u5173\u6ce8\u201c\u4e1a\u4f59\u8349\u201d\u516c\u4f17\u53f7\u7559\u8a00\u8ba8\u8bba\u3002<\/p>\n<!-- <audio autoplay=\"autoplay\" height=\"100\" width=\"100\" hidden=\"true\"><source src=\"https:\/\/c.coka.la\/orAvPR.mp3\" type=\"audio\/mp3\"\/><\/audio><img decoding=\"async\" src=\"https:\/\/images.weserv.nl\/?url=https:\/\/ws3.sinaimg.cn\/large\/8fa5dcfcgy1g4em3rzar5j20ib089ae0.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/> --><p><!-- <img decoding=\"async\" src=\"https:\/\/raw.githubusercontent.com\/xmt1139057136\/xttblog\/master\/8fa5dcfcgy1g4em3rzar5j20ib089ae0.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/>--><img decoding=\"async\" src=\"https:\/\/saas.51autoparts.cn\/api\/admin\/sys-file\/oss\/file?fileName=84db51f8561e448f9a4fda2eff0811f9.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/><\/p><p>\u6700\u540e\uff0c\u6b22\u8fce\u5173\u6ce8\u6211\u7684\u4e2a\u4eba\u5fae\u4fe1\u516c\u4f17\u53f7\uff1a\u4e1a\u4f59\u8349\uff08yyucao\uff09\uff01<b>\u53ef\u52a0\u4f5c\u8005\u5fae\u4fe1\u53f7\uff1a<font color=\"red\">xttblog2<\/font>\u3002\u5907\u6ce8\uff1a\u201c1\u201d\uff0c\u6dfb\u52a0\u535a\u4e3b\u5fae\u4fe1\u62c9\u4f60\u8fdb\u5fae\u4fe1\u7fa4\u3002\u5907\u6ce8\u9519\u8bef\u4e0d\u4f1a\u540c\u610f\u597d\u53cb\u7533\u8bf7\u3002<\/b>\u518d\u6b21\u611f\u8c22\u60a8\u7684\u5173\u6ce8\uff01\u540e\u7eed\u6709\u7cbe\u5f69\u5185\u5bb9\u4f1a\u7b2c\u4e00\u65f6\u95f4\u53d1\u7ed9\u60a8\uff01\u539f\u521b\u6587\u7ae0\u6295\u7a3f\u8bf7\u53d1\u9001\u81f3532009913@qq.com\u90ae\u7bb1\u3002\u5546\u52a1\u5408\u4f5c\u4e5f\u53ef\u6dfb\u52a0\u4f5c\u8005\u5fae\u4fe1\u8fdb\u884c\u8054\u7cfb\uff01<\/p><p>\u672c\u6587\u539f\u6587\u51fa\u5904\uff1a<a href=\"https:\/\/www.xttblog.com\">\u4e1a\u4f59\u8349<\/a>\uff1a &raquo; <a href=\"https:\/\/www.xttblog.com\/?p=5092\">\u9762\u8bd5\u5b98\uff1aMySQL\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u4e2d\u7684\u53ef\u91cd\u590d\u8bfb\u80fd\u9632\u5e7b\u8bfb\u5417?<\/a><\/p><!-- <div class=\"bd-reward-stl\"><button id=\"bdRewardBtn\"><span><\/span><\/button><\/div> 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[&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[83,97,2108,2109,62],"class_list":["post-5092","post","type-post","status-publish","format-standard","hentry","category-java","tag-mysql","tag-mysqldumpslow","tag-2108","tag-2109","tag-62"],"_links":{"self":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/5092","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=5092"}],"version-history":[{"count":2,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/5092\/revisions"}],"predecessor-version":[{"id":5094,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/5092\/revisions\/5094"}],"wp:attachment":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5092"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5092"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5092"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}