{"id":1721,"date":"2020-06-22T18:20:47","date_gmt":"2020-06-22T10:20:47","guid":{"rendered":"http:\/\/39.97.231.10\/?p=1721"},"modified":"2020-06-22T18:20:47","modified_gmt":"2020-06-22T10:20:47","slug":"mysql%e4%ba%8b%e5%8a%a1acid%e7%89%b9%e6%80%a7%e7%9a%84%e5%ae%9e%e7%8e%b0%e5%8e%9f%e7%90%86","status":"publish","type":"post","link":"http:\/\/www.weijing.co\/?p=1721","title":{"rendered":"MySQL\u4e8b\u52a1ACID\u7279\u6027\u7684\u5b9e\u73b0\u539f\u7406"},"content":{"rendered":"<div>\n<div>\n<div>\n<div>\u4e00\u3001\u524d\u63d0<\/div>\n<\/div>\n<\/div>\n<\/div>\n<article>\u5728MySQL\u4e4bbinlog\u65e5\u5fd7\u3001undo\u65e5\u5fd7\u3001redo\u65e5\u5fd7\u8fd9\u7bc7\u6587\u7ae0\u4e2d\uff0c\u6211\u4eec\u7b80\u5355\u4ecb\u7ecd\u4e86MySql\u7684\u4e09\u79cd\u65e5\u5fd7\u3002\u5176\u4e2dundo\u65e5\u5fd7\u3001redo\u65e5\u5fd7\uff0c\u662f\u5b9e\u73b0MySQL\u4e8b\u52a1\u7684\u5173\u952e\uff1aredo log\u7528\u4e8e\u4fdd\u8bc1\u4e8b\u52a1\u6301\u4e45\u6027\uff1bundo log\u5219\u662f\u4e8b\u52a1\u539f\u5b50\u6027\u548c\u9694\u79bb\u6027\u5b9e\u73b0\u7684\u57fa\u7840\u3002<\/p>\n<h1>\u4e8c\u3001\u6570\u636e\u5e93\u4e8b\u52a1\u7684\u7279\u6027<\/h1>\n<ul>\n<li>\u539f\u5b50\u6027\uff08A: Atomicity\uff09<br \/>\n\u6240\u8c13\u7684\u539f\u5b50\u6027\u662f\u6307\uff0c\u6574\u4e2a\u4e8b\u52a1\u4e2d\u7684\u6240\u6709\u64cd\u4f5c\uff0c\u8981\u4e48\u5168\u90e8\u5b8c\u6210\uff0c\u8981\u4e48\u5168\u90e8\u56de\u6eda\u5230\u4e8b\u52a1\u521d\u59cb\u72b6\u6001\uff0c\u4e0d\u5b58\u5728\u6709\u7684\u6210\u529f\u6709\u7684\u5931\u8d25\u8fd9\u6837\u7684\u4e2d\u95f4\u72b6\u6001\u3002\u4e8b\u52a1\u5728\u6267\u884c\u4e2d\u53d1\u751f\u9519\u8bef\uff0c\u6240\u6709\u7684\u64cd\u4f5c\u90fd\u4f1a\u88ab\u56de\u6eda\uff0c\u6574\u4e2a\u4e8b\u52a1\u5c31\u50cf\u4ece\u6ca1\u88ab\u6267\u884c\u8fc7\u4e00\u6837\u3002<\/li>\n<li>\u4e00\u81f4\u6027\uff08C: Consistency\uff09<br \/>\n\u6240\u8c13\u7684\u4e00\u81f4\u6027\u6307\uff0c\u4e00\u4e2a\u4e8b\u52a1\u6267\u884c\u4e4b\u524d\u3001\u540e\u6570\u636e\u5e93\u90fd\u5fc5\u987b\u5904\u4e8e\u4e00\u81f4\u6027\u72b6\u6001\u3002\u5373\uff1a<br \/>\n\u4e8b\u52a1\u6267\u884c\u6210\u529f\uff0c\u7cfb\u7edf\u4e2d\u6240\u6709\u53d8\u5316\u5c06\u6b63\u786e\u5730\u5e94\u7528\uff0c\u7cfb\u7edf\u5904\u4e8e\u6709\u6548\u72b6\u6001\u3002<br \/>\n\u4e8b\u52a1\u6267\u884c\u51fa\u9519\uff0c\u7cfb\u7edf\u4e2d\u7684\u6240\u6709\u53d8\u5316\u5c06\u81ea\u52a8\u5730\u56de\u6eda\uff0c\u7cfb\u7edf\u8fd4\u56de\u5230\u539f\u59cb\u72b6\u6001\u3002<br \/>\n\u4ee5\u8f6c\u8d26\u4e3a\u4f8b\uff0cA\u6709500\u5143\uff0cB\u6709300\u5143\uff0c\u5982\u679c\u5728\u4e00\u4e2a\u4e8b\u52a1\u91ccA\u6210\u529f\u8f6c50\u5143\u7ed9B\uff0c\u90a3\u4e48\u4e0d\u7ba1\u5e76\u53d1\u591a\u5c11\uff0c\u4e0d\u7ba1\u53d1\u751f\u4ec0\u4e48\uff0c\u53ea\u8981\u4e8b\u52a1\u6267\u884c\u6210\u529f\u4e86\uff0c\u90a3\u4e48\u6700\u540eA\u8d26\u6237\u4e00\u5b9a\u662f450\u5143\uff0cB\u8d26\u6237\u4e00\u5b9a\u662f350\u5143\u3002<\/li>\n<li>\u9694\u79bb\u6027\uff08I: Isolation\uff09<br \/>\n\u6240\u8c13\u7684\u9694\u79bb\u6027\u662f\u6307\uff0c\u4e8b\u52a1\u4e0e\u4e8b\u52a1\u4e4b\u95f4\u4e0d\u4f1a\u4e92\u76f8\u5f71\u54cd\uff0c\u4e00\u4e2a\u4e8b\u52a1\u7684\u4e2d\u95f4\u72b6\u6001\u4e0d\u4f1a\u88ab\u5176\u4ed6\u4e8b\u52a1\u611f\u77e5\u3002\u5373\uff1a<br \/>\n\u5728\u5e76\u53d1\u73af\u5883\u4e2d\uff0c\u5f53\u4e0d\u540c\u7684\u4e8b\u52a1\u540c\u65f6\u64cd\u7eb5\u76f8\u540c\u7684\u6570\u636e\u65f6\uff0c\u6bcf\u4e2a\u4e8b\u52a1\u90fd\u6709\u5404\u81ea\u5b8c\u6574\u7684\u6570\u636e\u7a7a\u95f4\u3002\u4e8b\u52a1\u67e5\u770b\u6570\u636e\u66f4\u65b0\u65f6\uff0c\u6570\u636e\u6240\u5904\u7684\u72b6\u6001\u00a0\u8981\u4e48\u662f\u53e6\u4e00\u4e8b\u52a1\u4fee\u6539\u5b83\u4e4b\u524d\u7684\u72b6\u6001\uff0c\u8981\u4e48\u662f\u53e6\u4e00\u4e8b\u52a1\u4fee\u6539\u5b83\u4e4b\u540e\u7684\u72b6\u6001\uff0c\u4e8b\u52a1\u4e0d\u4f1a\u67e5\u770b\u5230\u4e2d\u95f4\u72b6\u6001\u7684\u6570\u636e\u3002<\/li>\n<li>\u6301\u4e45\u6027\uff08D: Durability\uff09<br \/>\n\u6240\u8c13\u7684\u6301\u4e45\u6027\u662f\u6307\uff0c\u4e00\u65e6\u4e8b\u52a1\u63d0\u4ea4\u5b8c\u6210\uff0c\u90a3\u4e48\u4e8b\u52a1\u5bf9\u6570\u636e\u6240\u505a\u7684\u53d8\u66f4\u5c31\u5b8c\u5168\u4fdd\u5b58\u5728\u4e86\u6570\u636e\u5e93\u4e2d\uff0c\u5373\u4f7f\u53d1\u751f\u505c\u7535\uff0c\u7cfb\u7edf\u5b95\u673a\u4e5f\u4e0d\u4f1a\u6539\u53d8\uff0c\u6216\u8005\u8bf4\u53ef\u4ee5\u6062\u590d\u5230\u4e8b\u52a1\u6210\u529f\u63d0\u4ea4\u540e\u7684\u72b6\u6001\u3002<\/li>\n<\/ul>\n<h1>\u4e00\u3001\u5404\u4e2a\u7279\u6027\u7684\u5b9e\u73b0\u539f\u7406<\/h1>\n<p>\u4e8b\u52a1\u7684\u56db\u5927\u7279\u6027\u4e2d\uff0c\u539f\u5b50\u6027\u3001\u9694\u79bb\u6027\u3001\u6301\u4e45\u6027\u90fd\u662f\u4e3a\u4e86\u4e00\u81f4\u6027\u670d\u52a1\u7684\u3002\u5373\uff0c\u90fd\u662f\u4e3a\u4e86\u4fdd\u8bc1\u6700\u540e\u7684\u6570\u636e\u4e00\u81f4\u7684\u3002<\/p>\n<h3>1. \u539f\u5b50\u6027<\/h3>\n<p>undo log\u662f\u5b9e\u73b0\u4e8b\u52a1\u539f\u5b50\u6027\u7684\u5173\u952e\uff0c\u5f53\u4e8b\u52a1\u56de\u6eda\u65f6\u80fd\u591f\u64a4\u9500\u6240\u6709\u5df2\u7ecf\u6210\u529f\u6267\u884c\u7684sql\u8bed\u53e5\u3002<br \/>\n\u8fc7\u7a0b\uff1a<\/p>\n<ul>\n<li>\u5f53\u4e8b\u52a1\u5bf9\u6570\u636e\u5e93\u8fdb\u884c\u4fee\u6539\u65f6\uff0cInnoDB\u4f1a\u751f\u6210\u5bf9\u5e94\u7684undo log\uff1b<\/li>\n<li>\u5982\u679c\u4e8b\u52a1\u6267\u884c\u5931\u8d25\u6216\u8c03\u7528\u4e86rollback\uff0c\u5bfc\u81f4\u4e8b\u52a1\u9700\u8981\u56de\u6eda\uff0c\u4fbf\u53ef\u4ee5\u5229\u7528undo log\u4e2d\u7684\u4fe1\u606f\u5c06\u6570\u636e\u56de\u6eda\u5230\u4fee\u6539\u4e4b\u524d\u7684\u6837\u5b50\u3002<\/li>\n<\/ul>\n<p>undo log\u5c5e\u4e8e\u903b\u8f91\u65e5\u5fd7\uff0c\u5b83\u8bb0\u5f55\u7684\u662fsql\u6267\u884c\u76f8\u5173\u7684\u4fe1\u606f\u3002<br \/>\n\u5f53\u53d1\u751f\u56de\u6eda\u65f6\uff0cInnoDB\u4f1a\u6839\u636eundo log\u7684\u5185\u5bb9\u505a\u4e0e\u4e4b\u524d\u76f8\u53cd\u7684\u5de5\u4f5c\uff1a\u5bf9\u4e8e\u6bcf\u4e2ainsert\uff0c\u56de\u6eda\u65f6\u4f1a\u6267\u884cdelete\uff1b\u5bf9\u4e8e\u6bcf\u4e2adelete\uff0c\u56de\u6eda\u65f6\u4f1a\u6267\u884cinsert\uff1b\u5bf9\u4e8e\u6bcf\u4e2aupdate\uff0c\u56de\u6eda\u65f6\u4f1a\u6267\u884c\u4e00\u4e2a\u76f8\u53cd\u7684update\uff0c\u628a\u6570\u636e\u6539\u56de\u53bb\u3002<br \/>\n\u4ee5update\u64cd\u4f5c\u4e3a\u4f8b\uff1a\u5f53\u4e8b\u52a1\u6267\u884cupdate\u65f6\uff0c\u5176\u751f\u6210\u7684undo log\u4e2d\u4f1a\u5305\u542b\u88ab\u4fee\u6539\u884c\u7684\u4e3b\u952e(\u4ee5\u4fbf\u77e5\u9053\u4fee\u6539\u4e86\u54ea\u4e9b\u884c)\u3001\u4fee\u6539\u4e86\u54ea\u4e9b\u5217\u3001\u8fd9\u4e9b\u5217\u5728\u4fee\u6539\u524d\u540e\u7684\u503c\u7b49\u4fe1\u606f\uff0c\u56de\u6eda\u65f6\u4fbf\u53ef\u4ee5\u4f7f\u7528\u8fd9\u4e9b\u4fe1\u606f\u5c06\u6570\u636e\u8fd8\u539f\u5230update\u4e4b\u524d\u7684\u72b6\u6001\u3002<\/p>\n<h3>2. \u6301\u4e45\u6027<\/h3>\n<p>redo log\u662f\u5b9e\u73b0\u4e8b\u52a1\u6301\u4e45\u6027\u7684\u5173\u952e\uff0c\u662fInnoDB\u7279\u6709\u7684\u65e5\u5fd7\u3002<br \/>\nInnoDB\u4f5c\u4e3aMySQL\u7684\u5b58\u50a8\u5f15\u64ce\uff0c\u6570\u636e\u662f\u5b58\u653e\u5728\u78c1\u76d8\u4e2d\u7684\uff0c\u4f46\u5982\u679c\u6bcf\u6b21\u8bfb\u5199\u6570\u636e\u90fd\u9700\u8981\u78c1\u76d8IO\uff0c\u6548\u7387\u4f1a\u5f88\u4f4e\u3002<br \/>\n\u4e3a\u6b64\uff0cInnoDB\u63d0\u4f9b\u4e86\u7f13\u5b58(Buffer Pool)\uff0cBuffer Pool\u4e2d\u5305\u542b\u4e86\u78c1\u76d8\u4e2d\u90e8\u5206\u6570\u636e\u9875\u7684\u6620\u5c04\uff0c\u4f5c\u4e3a\u8bbf\u95ee\u6570\u636e\u5e93\u7684\u7f13\u51b2\uff1a\u5f53\u4ece\u6570\u636e\u5e93\u8bfb\u53d6\u6570\u636e\u65f6\uff0c\u4f1a\u9996\u5148\u4eceBuffer Pool\u4e2d\u8bfb\u53d6\uff0c\u5982\u679cBuffer Pool\u4e2d\u6ca1\u6709\uff0c\u5219\u4ece\u78c1\u76d8\u8bfb\u53d6\u540e\u653e\u5165Buffer Pool\uff1b<br \/>\n\u5f53\u5411\u6570\u636e\u5e93\u5199\u5165\u6570\u636e\u65f6\uff0c\u4f1a\u9996\u5148\u5199\u5165Buffer Pool\uff0cBuffer Pool\u4e2d\u4fee\u6539\u7684\u6570\u636e\u4f1a\u5b9a\u671f\u5237\u65b0\u5230\u78c1\u76d8\u4e2d\uff08\u8fd9\u4e00\u8fc7\u7a0b\u79f0\u4e3a\u5237\u810f\uff09\u3002<br \/>\nBuffer Pool\u7684\u4f7f\u7528\u5927\u5927\u63d0\u9ad8\u4e86\u8bfb\u5199\u6570\u636e\u7684\u6548\u7387\uff0c\u4f46\u662f\u4e5f\u5e26\u4e86\u65b0\u7684\u95ee\u9898\uff1a<br \/>\n\u5982\u679cMySQL\u5b95\u673a\uff0c\u800c\u6b64\u65f6Buffer Pool\u4e2d\u4fee\u6539\u7684\u6570\u636e\u8fd8\u6ca1\u6709\u5237\u65b0\u5230\u78c1\u76d8\uff0c\u5c31\u4f1a\u5bfc\u81f4\u6570\u636e\u7684\u4e22\u5931\uff0c\u4e8b\u52a1\u7684\u6301\u4e45\u6027\u65e0\u6cd5\u4fdd\u8bc1\u3002<br \/>\n\u4e8e\u662f\uff0credo log\u88ab\u5f15\u5165\u6765\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898\uff1a<\/p>\n<ol>\n<li>\u5f53\u6570\u636e\u4fee\u6539\u65f6\uff0c\u9664\u4e86\u4fee\u6539Buffer Pool\u4e2d\u7684\u6570\u636e\uff0c\u8fd8\u4f1a\u5728redo log\u8bb0\u5f55\u8fd9\u6b21\u64cd\u4f5c\uff1b<\/li>\n<li>\u5f53\u4e8b\u52a1\u63d0\u4ea4\u65f6\uff0c\u4f1a\u8c03\u7528fsync\u63a5\u53e3\u5bf9redo log\u8fdb\u884c\u5237\u76d8\u3002\u5982\u679cMySQL\u5b95\u673a\uff0c\u91cd\u542f\u65f6\u53ef\u4ee5\u8bfb\u53d6redo log\u4e2d\u7684\u6570\u636e\uff0c\u5bf9\u6570\u636e\u5e93\u8fdb\u884c\u6062\u590d\u3002redo log\u91c7\u7528\u7684\u662fWAL\uff08Write-ahead logging\uff0c\u9884\u5199\u5f0f\u65e5\u5fd7\uff09\uff0c\u6240\u6709\u4fee\u6539\u5148\u5199\u5165\u65e5\u5fd7\uff0c\u518d\u66f4\u65b0\u5230Buffer Pool\uff0c\u4fdd\u8bc1\u4e86\u6570\u636e\u4e0d\u4f1a\u56e0MySQL\u5b95\u673a\u800c\u4e22\u5931\uff0c\u4ece\u800c\u6ee1\u8db3\u4e86\u6301\u4e45\u6027\u8981\u6c42\u3002<\/li>\n<\/ol>\n<p>\u65e2\u7136redo log\u4e5f\u9700\u8981\u5728\u4e8b\u52a1\u63d0\u4ea4\u65f6\u5c06\u65e5\u5fd7\u5199\u5165\u78c1\u76d8\uff0c\u4e3a\u4ec0\u4e48\u5b83\u6bd4\u76f4\u63a5\u5c06Buffer Pool\u4e2d\u4fee\u6539\u7684\u6570\u636e\u5199\u5165\u78c1\u76d8(\u5373\u5237\u810f)\u8981\u5feb\u5462\uff1f<br \/>\n\u4e3b\u8981\u6709\u4ee5\u4e0b\u4e24\u65b9\u9762\u7684\u539f\u56e0\uff1a<\/p>\n<ol>\n<li>\u5237\u810f\u662f\u968f\u673aIO\uff0c\u56e0\u4e3a\u6bcf\u6b21\u4fee\u6539\u7684\u6570\u636e\u4f4d\u7f6e\u968f\u673a\uff0c\u4f46\u5199redo log\u662f\u8ffd\u52a0\u64cd\u4f5c\uff0c\u5c5e\u4e8e\u987a\u5e8fIO\u3002<\/li>\n<li>\u5237\u810f\u662f\u4ee5\u6570\u636e\u9875\uff08Page\uff09\u4e3a\u5355\u4f4d\u7684\uff0cMySQL\u9ed8\u8ba4\u9875\u5927\u5c0f\u662f16KB\uff0c\u4e00\u4e2aPage\u4e0a\u4e00\u4e2a\u5c0f\u4fee\u6539\u90fd\u8981\u6574\u9875\u5199\u5165\uff1b\u800credo log\u4e2d\u53ea\u5305\u542b\u771f\u6b63\u9700\u8981\u5199\u5165\u7684\u90e8\u5206\uff0c\u65e0\u6548IO\u5927\u5927\u51cf\u5c11\u3002<\/li>\n<\/ol>\n<h3>3. \u9694\u79bb\u6027<\/h3>\n<ul>\n<li>\u9694\u79bb\u6027\u8ffd\u6c42\u7684\u662f\u5e76\u53d1\u60c5\u5f62\u4e0b\u4e8b\u52a1\u4e4b\u95f4\u4e92\u4e0d\u5e72\u6270\u3002InnoDB\u9ed8\u8ba4\u7684\u9694\u79bb\u7ea7\u522b\u662fRR\uff0cRR\u7684\u5b9e\u73b0\u4e3b\u8981\u57fa\u4e8e\u9501\u673a\u5236\u3001\u6570\u636e\u7684\u9690\u85cf\u5217\u3001undo log\u548c\u7c7bnext-key lock\u673a\u5236<\/li>\n<li>\u7b80\u5355\u8d77\u89c1\uff0c\u6211\u4eec\u4ec5\u8003\u8651\u6700\u7b80\u5355\u7684\u8bfb\u64cd\u4f5c\u548c\u5199\u64cd\u4f5c(\u6682\u65f6\u4e0d\u8003\u8651\u5e26\u9501\u8bfb\u7b49\u7279\u6b8a\u64cd\u4f5c)\uff0c\u90a3\u4e48\u9694\u79bb\u6027\u7684\u63a2\u8ba8\uff0c\u4e3b\u8981\u53ef\u4ee5\u5206\u4e3a\u4e24\u4e2a\u65b9\u9762\uff1a<br \/>\n(\u4e00\u4e2a\u4e8b\u52a1)\u5199\u64cd\u4f5c\u5bf9(\u53e6\u4e00\u4e2a\u4e8b\u52a1)\u5199\u64cd\u4f5c\u7684\u5f71\u54cd\uff1a\u9501\u673a\u5236\u4fdd\u8bc1\u9694\u79bb\u6027<br \/>\n(\u4e00\u4e2a\u4e8b\u52a1)\u5199\u64cd\u4f5c\u5bf9(\u53e6\u4e00\u4e2a\u4e8b\u52a1)\u8bfb\u64cd\u4f5c\u7684\u5f71\u54cd\uff1aMVCC\u4fdd\u8bc1\u9694\u79bb\u6027<\/li>\n<\/ul>\n<h4>3.1 \u9501\u673a\u5236<\/h4>\n<ul>\n<li>\u9694\u79bb\u6027\u8981\u6c42\u540c\u4e00\u65f6\u523b\u53ea\u80fd\u6709\u4e00\u4e2a\u4e8b\u52a1\u5bf9\u6570\u636e\u8fdb\u884c\u5199\u64cd\u4f5c\uff0cInnoDB\u901a\u8fc7\u9501\u673a\u5236\u6765\u4fdd\u8bc1\u8fd9\u4e00\u70b9\u3002<br \/>\n\u9501\u673a\u5236\u7684\u57fa\u672c\u539f\u7406\u53ef\u4ee5\u6982\u62ec\u4e3a\uff1a\u4e8b\u52a1\u5728\u4fee\u6539\u6570\u636e\u4e4b\u524d\uff0c\u9700\u8981\u5148\u83b7\u5f97\u76f8\u5e94\u7684\u9501\uff1b\u83b7\u5f97\u9501\u4e4b\u540e\uff0c\u4e8b\u52a1\u4fbf\u53ef\u4ee5\u4fee\u6539\u6570\u636e\uff1b\u8be5\u4e8b\u52a1\u64cd\u4f5c\u671f\u95f4\uff0c\u8fd9\u90e8\u5206\u6570\u636e\u662f\u9501\u5b9a\u7684\uff0c\u5176\u4ed6\u4e8b\u52a1\u5982\u679c\u9700\u8981\u4fee\u6539\u6570\u636e\uff0c\u9700\u8981\u7b49\u5f85\u5f53\u524d\u4e8b\u52a1\u63d0\u4ea4\u6216\u56de\u6eda\u540e\u91ca\u653e\u9501\u3002<\/li>\n<li>\u8868\u9501 \uff1a\u5728\u64cd\u4f5c\u6570\u636e\u65f6\u4f1a\u9501\u5b9a\u6574\u5f20\u8868\uff0c\u5e76\u53d1\u6027\u80fd\u8f83\u5dee<\/li>\n<li>\u884c\u9501 \uff1a\u53ea\u9501\u5b9a\u9700\u8981\u64cd\u4f5c\u7684\u6570\u636e\uff0c\u5e76\u53d1\u6027\u80fd\u597d<\/li>\n<\/ul>\n<p>\u67e5\u770bInnoDB\u4e2d\u9501\u7684\u60c5\u51b5\uff0c\u5982\u4e0b\uff1a<\/p>\n<div>\n<pre>select * from information_schema.innodb_locks; #\u9501\u7684\u6982\u51b5\nshow engine innodb status; #InnoDB\u6574\u4f53\u72b6\u6001\uff0c\u5176\u4e2d\u5305\u62ec\u9501\u7684\u60c5\u51b5\n<\/pre>\n<\/div>\n<p>\u770b\u4e00\u4e2a\u4f8b\u5b50\uff1a<\/p>\n<div>\n<pre>#\u5728\u4e8b\u52a1A\u4e2d\u6267\u884c\uff1a\nstart transaction;\nupdate account SET balance = 1000 where id = 1;\n#\u5728\u4e8b\u52a1B\u4e2d\u6267\u884c\uff1a\nstart transaction;\nupdate account SET balance = 2000 where id = 1;\n<\/pre>\n<\/div>\n<p>\u6b64\u65f6\u67e5\u770b\u9501\u7684\u60c5\u51b5\uff1a<\/p>\n<div>\n<div>\n<div><\/div>\n<div data-width=\\\"511\\\" data-height=\\\"136\\\"><img src=\\\"https:\/\/upload-images.jianshu.io\/upload_images\/12320828-ec1130afcd5f6a91.png?imageMogr2\/auto-orient\/strip|imageView2\/2\/w\/511\/format\/webp\\\" data-original-src=\\\"\/\/upload-images.jianshu.io\/upload_images\/12320828-ec1130afcd5f6a91.png\\\" data-original-width=\\\"511\\\" data-original-height=\\\"136\\\" data-original-format=\\\"image\/png\\\" data-original-filesize=\\\"85079\\\" data-image-index=\\\"0\\\" \/><\/div>\n<\/div>\n<\/div>\n<p>\u5176\u4e2d\uff0clock_type\u4e3aRECORD\uff0c\u4ee3\u8868\u9501\u4e3a\u884c\u9501(\u8bb0\u5f55\u9501)\uff1block_mode\u4e3aX\uff0c\u4ee3\u8868\u6392\u5b83\u9501(\u5199\u9501)\u3002<\/p>\n<h6>3.1.1\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/h6>\n<p>SQL\u6807\u51c6\u4e2d\u5b9a\u4e49\u4e86\u56db\u79cd\u9694\u79bb\u7ea7\u522b\uff0c\u5e76\u89c4\u5b9a\u4e86\u6bcf\u79cd\u9694\u79bb\u7ea7\u522b\u4e0b\u4e0a\u8ff0\u51e0\u4e2a\u95ee\u9898\u662f\u5426\u5b58\u5728\u3002\u4e00\u822c\u6765\u8bf4\uff0c\u9694\u79bb\u7ea7\u522b\u8d8a\u4f4e\uff0c\u7cfb\u7edf\u5f00\u9500\u8d8a\u4f4e\uff0c\u53ef\u652f\u6301\u7684\u5e76\u53d1\u8d8a\u9ad8\uff0c\u4f46\u9694\u79bb\u6027\u4e5f\u8d8a\u5dee\u3002\u9694\u79bb\u7ea7\u522b\u4e0e\u8bfb\u95ee\u9898\u7684\u5173\u7cfb\u5982\u4e0b\uff1a<\/p>\n<div>\n<div>\n<div><\/div>\n<div data-width=\\\"549\\\" data-height=\\\"368\\\"><img src=\\\"https:\/\/upload-images.jianshu.io\/upload_images\/12320828-23c73352a27b794e.png?imageMogr2\/auto-orient\/strip|imageView2\/2\/w\/549\/format\/webp\\\" data-original-src=\\\"\/\/upload-images.jianshu.io\/upload_images\/12320828-23c73352a27b794e.png\\\" data-original-width=\\\"549\\\" data-original-height=\\\"368\\\" data-original-format=\\\"image\/png\\\" data-original-filesize=\\\"112700\\\" data-image-index=\\\"1\\\" \/><\/div>\n<\/div>\n<\/div>\n<ul>\n<li>\u8d43\u8bfb\uff1a\u5f53\u524d\u4e8b\u52a1(A)\u4e2d\u53ef\u4ee5\u8bfb\u5230\u5176\u4ed6\u4e8b\u52a1(B)\u672a\u63d0\u4ea4\u7684\u6570\u636e\uff08\u810f\u6570\u636e\uff09\uff0c\u8fd9\u79cd\u73b0\u8c61\u662f\u810f\u8bfb\u3002\u4e3e\u4f8b\u5982\u4e0b\uff08\u4ee5\u8d26\u6237\u4f59\u989d\u8868\u4e3a\u4f8b\uff09\uff1a\n<div>\n<div>\n<div><\/div>\n<div data-width=\\\"1080\\\" data-height=\\\"570\\\"><img src=\\\"https:\/\/upload-images.jianshu.io\/upload_images\/12320828-be6fcca8d7b3a75a.png?imageMogr2\/auto-orient\/strip|imageView2\/2\/w\/1080\/format\/webp\\\" data-original-src=\\\"\/\/upload-images.jianshu.io\/upload_images\/12320828-be6fcca8d7b3a75a.png\\\" data-original-width=\\\"1080\\\" data-original-height=\\\"570\\\" data-original-format=\\\"image\/png\\\" data-original-filesize=\\\"210035\\\" data-image-index=\\\"2\\\" \/><\/div>\n<\/div>\n<\/div>\n<\/li>\n<li>\u4e0d\u53ef\u91cd\u590d\u8bfb\uff1a\u5728\u4e8b\u52a1A\u4e2d\u5148\u540e\u4e24\u6b21\u8bfb\u53d6\u540c\u4e00\u4e2a\u6570\u636e\uff0c\u4e24\u6b21\u8bfb\u53d6\u7684\u7ed3\u679c\u4e0d\u4e00\u6837\uff0c\u8fd9\u79cd\u73b0\u8c61\u79f0\u4e3a\u4e0d\u53ef\u91cd\u590d\u8bfb\u3002\u810f\u8bfb\u4e0e\u4e0d\u53ef\u91cd\u590d\u8bfb\u7684\u533a\u522b\u5728\u4e8e\uff1a\u524d\u8005\u8bfb\u5230\u7684\u662f\u5176\u4ed6\u4e8b\u52a1\u672a\u63d0\u4ea4\u7684\u6570\u636e\uff0c\u540e\u8005\u8bfb\u5230\u7684\u662f\u5176\u4ed6\u4e8b\u52a1\u5df2\u63d0\u4ea4\u7684\u6570\u636e\u3002\u4e3e\u4f8b\u5982\u4e0b\uff1a\n<div>\n<div>\n<div><\/div>\n<div data-width=\\\"1080\\\" data-height=\\\"732\\\"><img src=\\\"https:\/\/upload-images.jianshu.io\/upload_images\/12320828-b258473a25cb0ac9.png?imageMogr2\/auto-orient\/strip|imageView2\/2\/w\/1080\/format\/webp\\\" data-original-src=\\\"\/\/upload-images.jianshu.io\/upload_images\/12320828-b258473a25cb0ac9.png\\\" data-original-width=\\\"1080\\\" data-original-height=\\\"732\\\" data-original-format=\\\"image\/png\\\" data-original-filesize=\\\"271007\\\" data-image-index=\\\"3\\\" \/><\/div>\n<\/div>\n<\/div>\n<\/li>\n<li>\u5e7b\u8bfb\uff1a\u5728\u4e8b\u52a1A\u4e2d\u6309\u7167\u67d0\u4e2a\u6761\u4ef6\u5148\u540e\u4e24\u6b21\u67e5\u8be2\u6570\u636e\u5e93\uff0c\u4e24\u6b21\u67e5\u8be2\u7ed3\u679c\u7684\u6761\u6570\u4e0d\u540c\uff0c\u8fd9\u79cd\u73b0\u8c61\u79f0\u4e3a\u5e7b\u8bfb\u3002\u4e0d\u53ef\u91cd\u590d\u8bfb\u4e0e\u5e7b\u8bfb\u7684\u533a\u522b\u53ef\u4ee5\u901a\u4fd7\u7684\u7406\u89e3\u4e3a\uff1a\u524d\u8005\u662f\u6570\u636e\u53d8\u4e86\uff0c\u540e\u8005\u662f\u6570\u636e\u7684\u884c\u6570\u53d8\u4e86\u3002\u4e3e\u4f8b\u5982\u4e0b\uff1a\n<div>\n<div>\n<div><\/div>\n<div data-width=\\\"553\\\" data-height=\\\"496\\\"><img src=\\\"https:\/\/upload-images.jianshu.io\/upload_images\/12320828-774438b24de93aef.png?imageMogr2\/auto-orient\/strip|imageView2\/2\/w\/553\/format\/webp\\\" data-original-src=\\\"\/\/upload-images.jianshu.io\/upload_images\/12320828-774438b24de93aef.png\\\" data-original-width=\\\"553\\\" data-original-height=\\\"496\\\" data-original-format=\\\"image\/png\\\" data-original-filesize=\\\"119437\\\" data-image-index=\\\"4\\\" \/><\/div>\n<\/div>\n<\/div>\n<\/li>\n<\/ul>\n<h4>3.2 MVCC<\/h4>\n<ul>\n<li>MVCC (MultiVersion Concurrency Control) \u53eb\u505a\u591a\u7248\u672c\u5e76\u53d1\u63a7\u5236\u3002<\/li>\n<li>MVCC\u5728mysql\u4e2d\u7684\u5b9e\u73b0\u4f9d\u8d56\u7684\u662fundo log\u4e0eread view<br \/>\nundo log :undo log \u4e2d\u8bb0\u5f55\u67d0\u884c\u6570\u636e\u7684\u591a\u4e2a\u7248\u672c\u7684\u6570\u636e\u3002<br \/>\nread view :\u7528\u6765\u5224\u65ad\u5f53\u524d\u7248\u672c\u6570\u636e\u7684\u53ef\u89c1\u6027<\/li>\n<li>MVCC\u6700\u5927\u7684\u4f18\u70b9\u662f\u8bfb\u4e0d\u52a0\u9501\uff0c\u56e0\u6b64\u8bfb\u5199\u4e0d\u51b2\u7a81\uff0c\u5e76\u53d1\u6027\u80fd\u597d\u3002InnoDB\u5b9e\u73b0MVCC\uff0c\u591a\u4e2a\u7248\u672c\u7684\u6570\u636e\u53ef\u4ee5\u5171\u5b58\uff0c\u4e3b\u8981\u662f\u4f9d\u9760\u6570\u636e\u7684\u9690\u85cf\u5217(\u4e5f\u53ef\u4ee5\u79f0\u4e4b\u4e3a\u6807\u8bb0\u4f4d)\u548cundo log\u3002\u5176\u4e2d\u6570\u636e\u7684\u9690\u85cf\u5217\u5305\u62ec\u4e86\u8be5\u884c\u6570\u636e\u7684\u7248\u672c\u53f7\u3001\u5220\u9664\u65f6\u95f4\u3001\u6307\u5411undo log\u7684\u6307\u9488\u7b49\u7b49\uff1b\u5f53\u8bfb\u53d6\u6570\u636e\u65f6\uff0cMySQL\u53ef\u4ee5\u901a\u8fc7\u9690\u85cf\u5217\u5224\u65ad\u662f\u5426\u9700\u8981\u56de\u6eda\u5e76\u627e\u5230\u56de\u6eda\u9700\u8981\u7684undo log\uff0c\u4ece\u800c\u5b9e\u73b0MVCC<\/li>\n<\/ul>\n<div>\n<div>\n<div><\/div>\n<div data-width=\\\"1280\\\" data-height=\\\"536\\\"><img src=\\\"https:\/\/upload-images.jianshu.io\/upload_images\/12320828-dcca4d2fb6266445.png?imageMogr2\/auto-orient\/strip|imageView2\/2\/w\/1200\/format\/webp\\\" data-original-src=\\\"\/\/upload-images.jianshu.io\/upload_images\/12320828-dcca4d2fb6266445.png\\\" data-original-width=\\\"1280\\\" data-original-height=\\\"536\\\" data-original-format=\\\"image\/png\\\" data-original-filesize=\\\"145134\\\" data-image-index=\\\"5\\\" \/><\/div>\n<\/div>\n<\/div>\n<div>\n<div>\n<div><\/div>\n<div data-width=\\\"1280\\\" data-height=\\\"540\\\"><img src=\\\"https:\/\/upload-images.jianshu.io\/upload_images\/12320828-28e9d18ef28aa913.png?imageMogr2\/auto-orient\/strip|imageView2\/2\/w\/1200\/format\/webp\\\" data-original-src=\\\"\/\/upload-images.jianshu.io\/upload_images\/12320828-28e9d18ef28aa913.png\\\" data-original-width=\\\"1280\\\" data-original-height=\\\"540\\\" data-original-format=\\\"image\/png\\\" data-original-filesize=\\\"133982\\\" data-image-index=\\\"6\\\" \/><\/div>\n<\/div>\n<\/div>\n<\/article>\n","protected":false},"excerpt":{"rendered":"<p>\u4e00\u3001\u524d\u63d0 \u5728MySQL\u4e4bbinlog\u65e5\u5fd7\u3001undo\u65e5\u5fd7\u3001redo\u65e5\u5fd7\u8fd9\u7bc7\u6587\u7ae0\u4e2d\uff0c\u6211\u4eec\u7b80\u5355\u4ecb\u7ecd\u4e86MySql\u7684\u4e09\u79cd &hellip;<\/p>\n<p class=\"read-more\"> <a class=\"\" href=\"http:\/\/www.weijing.co\/?p=1721\"> <span class=\"screen-reader-text\">MySQL\u4e8b\u52a1ACID\u7279\u6027\u7684\u5b9e\u73b0\u539f\u7406<\/span> \u67e5\u770b\u5168\u6587 &raquo;<\/a><\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"default","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":""},"categories":[90,88],"tags":[],"uagb_featured_image_src":{"full":false,"thumbnail":false,"medium":false,"medium_large":false,"large":false,"1536x1536":false,"2048x2048":false,"mailpoet_newsletter_max":false,"woocommerce_thumbnail":false,"woocommerce_single":false,"woocommerce_gallery_thumbnail":false,"shop_catalog":false,"shop_single":false,"shop_thumbnail":false},"uagb_author_info":{"display_name":"weijing","author_link":"http:\/\/www.weijing.co\/?author=4"},"uagb_comment_info":0,"uagb_excerpt":"\u4e00\u3001\u524d\u63d0 \u5728MySQL\u4e4bbinlog\u65e5\u5fd7\u3001undo\u65e5\u5fd7\u3001redo\u65e5\u5fd7\u8fd9\u7bc7\u6587\u7ae0\u4e2d\uff0c\u6211\u4eec\u7b80\u5355\u4ecb\u7ecd\u4e86MySql\u7684\u4e09\u79cd&hellip;","_links":{"self":[{"href":"http:\/\/www.weijing.co\/index.php?rest_route=\/wp\/v2\/posts\/1721"}],"collection":[{"href":"http:\/\/www.weijing.co\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.weijing.co\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.weijing.co\/index.php?rest_route=\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"http:\/\/www.weijing.co\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1721"}],"version-history":[{"count":0,"href":"http:\/\/www.weijing.co\/index.php?rest_route=\/wp\/v2\/posts\/1721\/revisions"}],"wp:attachment":[{"href":"http:\/\/www.weijing.co\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1721"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.weijing.co\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1721"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.weijing.co\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1721"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}