{"id":120649,"date":"2026-10-31T23:48:28","date_gmt":"2026-10-31T15:48:28","guid":{"rendered":"https:\/\/www.wsisp.com\/helps\/120649.html"},"modified":"2026-10-31T23:48:28","modified_gmt":"2026-10-31T15:48:28","slug":"mysql-%e5%9f%ba%e7%a1%80%e7%af%87%ef%bc%88%e5%8d%81%e4%b8%80%ef%bc%89%ef%bc%9a%e4%ba%8b%e5%8a%a1%e4%b8%8e%e9%9a%94%e7%a6%bb%e7%ba%a7%e5%88%ab","status":"publish","type":"post","link":"https:\/\/www.wsisp.com\/helps\/120649.html","title":{"rendered":"MySQL \u57fa\u7840\u7bc7\uff08\u5341\u4e00\uff09\uff1a\u4e8b\u52a1\u4e0e\u9694\u79bb\u7ea7\u522b"},"content":{"rendered":"

\u76ee\u5f55<\/p>\n

\n

\u672c\u6587\u5185\u5bb9\u6982\u8981<\/p>\n

\u4e00\u3001\u8ba4\u8bc6\u4e8b\u52a1<\/p>\n

1.1 \u4ec0\u4e48\u662f\u4e8b\u52a1<\/p>\n

1.2 \u4e3a\u4ec0\u4e48\u9700\u8981\u4e8b\u52a1<\/p>\n

1.3 \u4e8b\u52a1\u7684\u56db\u5927\u7279\u6027（ACID）<\/p>\n

1.3.1 \u539f\u5b50\u6027（Atomicity）<\/p>\n

1.3.2 \u4e00\u81f4\u6027（Consistency）<\/p>\n

1.3.3 \u9694\u79bb\u6027（Isolation）<\/p>\n

1.3.4 \u6301\u4e45\u6027（Durability）<\/p>\n

\u4e8c\u3001\u4e8b\u52a1\u7684\u57fa\u672c\u64cd\u4f5c<\/p>\n

2.1 MySQL \u7684\u81ea\u52a8\u63d0\u4ea4\u673a\u5236<\/p>\n

2.2 \u5f00\u542f\u4e8b\u52a1<\/p>\n

2.3 \u63d0\u4ea4\u4e8b\u52a1<\/p>\n

2.5 \u4fdd\u5b58\u70b9\u00a0<\/p>\n

2.6 \u5b9e\u6218：\u6a21\u62df\u94f6\u884c\u8f6c\u8d26<\/p>\n

2.6.1 \u521b\u5efa\u6d4b\u8bd5\u6570\u636e<\/p>\n

2.6.2 \u6267\u884c\u8f6c\u8d26\u4e8b\u52a1<\/p>\n

2.6.3 \u9a8c\u8bc1\u4e8b\u52a1\u56de\u6eda<\/p>\n

\u4e09\u3001\u5e76\u53d1\u4e8b\u52a1\u5e26\u6765\u7684\u95ee\u9898<\/p>\n

3.1\u00a0\u810f\u8bfb<\/p>\n

3.2 \u4e0d\u53ef\u91cd\u590d\u8bfb<\/p>\n

3.3 \u5e7b\u8bfb<\/p>\n

3.4\u00a0\u4e22\u5931\u66f4\u65b0<\/p>\n

\u56db\u3001\u4e8b\u52a1\u7684\u9694\u79bb\u7ea7\u522b<\/p>\n

4.1 MySQL \u7684\u56db\u79cd\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/p>\n

4.2 \u8bfb\u672a\u63d0\u4ea4（READ UNCOMMITTED）<\/p>\n

4.3 \u8bfb\u5df2\u63d0\u4ea4（READ COMMITTED）<\/p>\n

4.4 \u53ef\u91cd\u590d\u8bfb（REPEATABLE READ）<\/p>\n

4.5 \u4e32\u884c\u5316（SERIALIZABLE）<\/p>\n

4.6 \u67e5\u770b\u4e0e\u8bbe\u7f6e\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/p>\n

4.6.1 \u67e5\u770b\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/p>\n

4.6.2 \u8bbe\u7f6e\u4f1a\u8bdd\u7ea7\u522b\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/p>\n

4.6.3 \u8bbe\u7f6e\u5168\u5c40\u7ea7\u522b\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/p>\n

\n

\n

\u672c\u6587\u5185\u5bb9\u6982\u8981<\/h2>\n

\u672c\u6587\u4e3b\u8981\u4ecb\u7ecd MySQL \u4e8b\u52a1\u7684\u57fa\u672c\u6982\u5ff5\u3001\u57fa\u672c\u64cd\u4f5c\u4ee5\u53ca\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b，\u5e2e\u52a9\u8bfb\u8005\u7406\u89e3\u4e8b\u52a1\u5728\u6570\u636e\u5e93\u64cd\u4f5c\u4e2d\u7684\u4f5c\u7528，\u4ee5\u53ca\u5e76\u53d1\u4e8b\u52a1\u53ef\u80fd\u5e26\u6765\u7684\u95ee\u9898\u3002<\/p>\n

\u672c\u6587\u4e3b\u8981\u5185\u5bb9\u5982\u4e0b：<\/p>\n

  • \n

    \u8ba4\u8bc6\u4e8b\u52a1： \u4ecb\u7ecd\u4e8b\u52a1\u7684\u57fa\u672c\u6982\u5ff5\u3001\u4f7f\u7528\u4e8b\u52a1\u7684\u539f\u56e0，\u4ee5\u53ca ACID \u56db\u5927\u7279\u6027\u3002<\/p>\n<\/li>\n

  • \n

    \u4e8b\u52a1\u7684\u57fa\u672c\u64cd\u4f5c： \u4ecb\u7ecd\u81ea\u52a8\u63d0\u4ea4\u673a\u5236\u3001\u4e8b\u52a1\u7684\u5f00\u542f\u3001\u63d0\u4ea4\u3001\u56de\u6eda\u4e0e\u4fdd\u5b58\u70b9，\u5e76\u901a\u8fc7\u94f6\u884c\u8f6c\u8d26\u6848\u4f8b\u8fdb\u884c\u6f14\u793a\u3002<\/p>\n<\/li>\n

  • \n

    \u5e76\u53d1\u4e8b\u52a1\u5e26\u6765\u7684\u95ee\u9898： \u4ecb\u7ecd\u810f\u8bfb\u3001\u4e0d\u53ef\u91cd\u590d\u8bfb\u3001\u5e7b\u8bfb\u548c\u4e22\u5931\u66f4\u65b0，\u5206\u6790\u8fd9\u4e9b\u95ee\u9898\u7684\u4ea7\u751f\u539f\u56e0\u3002<\/p>\n<\/li>\n

  • \n

    \u4e8b\u52a1\u7684\u9694\u79bb\u7ea7\u522b： \u4ecb\u7ecd\u8bfb\u672a\u63d0\u4ea4\u3001\u8bfb\u5df2\u63d0\u4ea4\u3001\u53ef\u91cd\u590d\u8bfb\u548c\u4e32\u884c\u5316\u56db\u79cd\u9694\u79bb\u7ea7\u522b，\u5e76\u901a\u8fc7\u53cc\u4f1a\u8bdd\u5b9e\u9a8c\u89c2\u5bdf\u4e0d\u540c\u9694\u79bb\u7ea7\u522b\u4e0b\u7684\u4e8b\u52a1\u884c\u4e3a\u3002<\/p>\n<\/li>\n

  • \n

    \u9694\u79bb\u7ea7\u522b\u7684\u67e5\u770b\u4e0e\u8bbe\u7f6e： \u4ecb\u7ecd\u5982\u4f55\u67e5\u770b\u548c\u8bbe\u7f6e MySQL \u5168\u5c40\u53ca\u4f1a\u8bdd\u7ea7\u522b\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u3002<\/p>\n<\/li>\n

    \u901a\u8fc7\u672c\u6587\u7684\u5b66\u4e60，\u8bfb\u8005\u5e94\u8be5\u80fd\u591f\u638c\u63e1 MySQL \u4e8b\u52a1\u7684\u57fa\u672c\u4f7f\u7528\u65b9\u5f0f，\u7406\u89e3\u5e38\u89c1\u7684\u5e76\u53d1\u4e8b\u52a1\u95ee\u9898，\u5e76\u6839\u636e\u5b9e\u9645\u4e1a\u52a1\u9700\u6c42\u9009\u62e9\u5408\u9002\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u3002<\/p>\n

    \u81f3\u4e8e InnoDB \u7684 MVCC \u673a\u5236\u3001Undo Log\u3001Read View \u4ee5\u53ca\u6570\u636e\u8bb0\u5f55\u7684\u9690\u85cf\u5c5e\u6027\u7b49\u5e95\u5c42\u5b9e\u73b0\u539f\u7406，\u5c06\u5728\u540e\u7eed\u6587\u7ae0\u4e2d\u5355\u72ec\u4ecb\u7ecd\u3002<\/p>\n

    \u4e00\u3001\u8ba4\u8bc6\u4e8b\u52a1<\/h2>\n

    1.1 \u4ec0\u4e48\u662f\u4e8b\u52a1<\/h3>\n

    \u5728\u5b66\u4e60 MySQL \u7684\u8fc7\u7a0b\u4e2d，\u6211\u4eec\u9700\u8981\u7ecf\u5e38\u5bf9\u6570\u636e\u5e93\u4e2d\u7684\u6570\u636e\u8fdb\u884c CURD\u3002\u5728\u5b9e\u9645\u4e1a\u52a1\u4e2d，\u6709\u4e9b\u64cd\u4f5c\u5e76\u4e0d\u662f\u72ec\u7acb\u5b8c\u6210\u7684，\u800c\u662f\u9700\u8981\u591a\u4e2a\u64cd\u4f5c\u76f8\u4e92\u914d\u5408，\u5171\u540c\u5b8c\u6210\u4e00\u4e2a\u4e1a\u52a1\u76ee\u6807\u3002<\/p>\n

    \u4f8b\u5982，\u5728\u94f6\u884c\u8f6c\u8d26\u4e1a\u52a1\u4e2d，\u5047\u8bbe\u7528\u6237 A \u9700\u8981\u5411\u7528\u6237 B \u8f6c\u8d26 100 \u5143，\u5219\u9700\u8981\u5b8c\u6210\u4ee5\u4e0b\u4e24\u4e2a\u64cd\u4f5c：<\/p>\n

  • \n

    \u5c06\u7528\u6237 A \u7684\u8d26\u6237\u4f59\u989d\u51cf\u5c11 100 \u5143\u3002<\/p>\n<\/li>\n

  • \n

    \u5c06\u7528\u6237 B \u7684\u8d26\u6237\u4f59\u989d\u589e\u52a0 100 \u5143\u3002<\/p>\n<\/li>\n

    \u8fd9\u4e24\u4e2a\u64cd\u4f5c\u5171\u540c\u6784\u6210\u4e86\u4e00\u6b21\u5b8c\u6574\u7684\u8f6c\u8d26\u4e1a\u52a1\u3002<\/p>\n

    \u4f46\u662f，\u5982\u679c\u5728\u6267\u884c\u7b2c\u4e00\u4e2a\u64cd\u4f5c\u4e4b\u540e，\u6570\u636e\u5e93\u7a81\u7136\u53d1\u751f\u5f02\u5e38，\u5bfc\u81f4\u7b2c\u4e8c\u4e2a\u64cd\u4f5c\u6ca1\u6709\u6267\u884c，\u90a3\u4e48\u7528\u6237 A \u7684\u4f59\u989d\u5df2\u7ecf\u51cf\u5c11，\u800c\u7528\u6237 B \u7684\u4f59\u989d\u5374\u6ca1\u6709\u589e\u52a0\u3002\u8fd9\u5c31\u4f1a\u9020\u6210\u6570\u636e\u4e0d\u4e00\u81f4\u7684\u95ee\u9898\u3002<\/p>\n

    \u90a3\u4e48，\u5982\u4f55\u4fdd\u8bc1\u8fd9\u4e24\u4e2a\u64cd\u4f5c\u80fd\u591f\u4f5c\u4e3a\u4e00\u4e2a\u6574\u4f53\u6267\u884c\u5462？<\/p>\n

    \u8fd9\u5c31\u9700\u8981\u4f7f\u7528 \u4e8b\u52a1\u3002<\/p>\n

    \u4e8b\u52a1\u662f\u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edf\u63d0\u4f9b\u7684\u4e00\u79cd\u673a\u5236，\u7528\u4e8e\u5c06\u591a\u4e2a\u6570\u636e\u5e93\u64cd\u4f5c\u7ec4\u7ec7\u6210\u4e00\u4e2a\u903b\u8f91\u4e0a\u7684\u6574\u4f53\u3002\u4e8b\u52a1\u4e2d\u7684\u64cd\u4f5c\u8981\u4e48\u5168\u90e8\u6210\u529f，\u8981\u4e48\u5168\u90e8\u5931\u8d25，\u4ece\u800c\u4fdd\u8bc1\u6570\u636e\u7684\u4e00\u81f4\u6027\u3002<\/span><\/p>\n

    \u5bf9\u4e8e\u4e0a\u8ff0\u8f6c\u8d26\u4e1a\u52a1，\u6211\u4eec\u53ef\u4ee5\u5c06\u6263\u6b3e\u548c\u5165\u8d26\u4e24\u4e2a\u64cd\u4f5c\u653e\u5728\u540c\u4e00\u4e2a\u4e8b\u52a1\u4e2d：<\/p>\n

      \n
    • \n

      \u5982\u679c\u4e24\u4e2a\u64cd\u4f5c\u90fd\u6210\u529f\u6267\u884c，\u5c31\u63d0\u4ea4\u4e8b\u52a1，\u4f7f\u4fee\u6539\u7ed3\u679c\u751f\u6548\u3002<\/p>\n<\/li>\n

    • \n

      \u5982\u679c\u6267\u884c\u8fc7\u7a0b\u4e2d\u53d1\u751f\u5f02\u5e38，\u5c31\u56de\u6eda\u4e8b\u52a1，\u64a4\u9500\u672c\u6b21\u4e8b\u52a1\u4e2d\u5c1a\u672a\u63d0\u4ea4\u7684\u4fee\u6539\u3002<\/p>\n<\/li>\n<\/ul>\n

      \u901a\u8fc7\u8fd9\u79cd\u65b9\u5f0f，\u6211\u4eec\u5c31\u53ef\u4ee5\u907f\u514d\u53ea\u5b8c\u6210\u90e8\u5206\u64cd\u4f5c\u800c\u5bfc\u81f4\u7684\u6570\u636e\u4e0d\u4e00\u81f4\u95ee\u9898\u3002<\/p>\n

      \u9700\u8981\u6ce8\u610f\u7684\u662f，\u4e8b\u52a1\u5e76\u4e0d\u610f\u5473\u7740\u591a\u4e2a SQL \u8bed\u53e5\u4f1a\u81ea\u52a8\u6267\u884c\u3002\u6211\u4eec\u4ecd\u7136\u9700\u8981\u7f16\u5199\u76f8\u5e94\u7684 SQL \u8bed\u53e5，\u800c\u4e8b\u52a1\u8d1f\u8d23\u7ba1\u7406\u8fd9\u4e9b\u64cd\u4f5c\u4e4b\u95f4\u7684\u6574\u4f53\u6027\u3002<\/p>\n

      1.2 \u4e3a\u4ec0\u4e48\u9700\u8981\u4e8b\u52a1<\/h3>\n

      \u7406\u89e3\u4e86\u4e8b\u52a1\u7684\u57fa\u672c\u6982\u5ff5\u4e4b\u540e，\u6211\u4eec\u518d\u6765\u601d\u8003\u4e00\u4e2a\u95ee\u9898：\u5982\u679c\u6ca1\u6709\u4e8b\u52a1，\u4f1a\u53d1\u751f\u4ec0\u4e48？<\/p>\n

      \u4ecd\u7136\u4ee5\u94f6\u884c\u8f6c\u8d26\u4e3a\u4f8b，\u5047\u8bbe\u7528\u6237 A \u7684\u4f59\u989d\u4e3a 1000 \u5143，\u7528\u6237 B \u7684\u4f59\u989d\u4e3a 500 \u5143，\u73b0\u5728 A \u5411 B \u8f6c\u8d26 100 \u5143\u3002<\/p>\n

      \u8f6c\u8d26\u524d，\u8d26\u6237\u72b6\u6001\u5982\u4e0b：<\/p>\n\n\n\u7528\u6237\u8d26\u6237\u4f59\u989d<\/tr>\n\n\n\n
      A<\/td>\n1000 \u5143<\/td>\n<\/tr>\n
      B<\/td>\n500 \u5143<\/td>\n<\/tr>\n
      \u603b\u4f59\u989d<\/td>\n1500 \u5143<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

      \u6b63\u5e38\u60c5\u51b5\u4e0b，\u8f6c\u8d26\u5b8c\u6210\u4e4b\u540e，\u8d26\u6237\u72b6\u6001\u5e94\u8be5\u53d8\u4e3a：<\/p>\n\n\n\u7528\u6237\u8d26\u6237\u4f59\u989d<\/tr>\n\n\n\n
      A<\/td>\n900 \u5143<\/td>\n<\/tr>\n
      B<\/td>\n600 \u5143<\/td>\n<\/tr>\n
      \u603b\u4f59\u989d<\/td>\n1500 \u5143<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

      \u53ef\u4ee5\u770b\u5230，\u8f6c\u8d26\u53ea\u662f\u6539\u53d8\u4e86\u8d44\u91d1\u5728\u4e24\u4e2a\u8d26\u6237\u4e4b\u95f4\u7684\u5206\u914d，\u5e76\u6ca1\u6709\u6539\u53d8\u4e24\u4e2a\u8d26\u6237\u7684\u603b\u4f59\u989d\u3002<\/p>\n

      \u4f46\u662f，\u5982\u679c\u6ca1\u6709\u4e8b\u52a1\u7684\u7ba1\u7406，\u5047\u8bbe A \u7684\u6263\u6b3e\u64cd\u4f5c\u5df2\u7ecf\u6210\u529f，\u800c B \u7684\u5165\u8d26\u64cd\u4f5c\u56e0\u4e3a\u67d0\u79cd\u539f\u56e0\u5931\u8d25，\u90a3\u4e48\u6570\u636e\u5e93\u4e2d\u7684\u72b6\u6001\u5c31\u4f1a\u53d8\u6210：<\/p>\n\n\n\u7528\u6237\u8d26\u6237\u4f59\u989d<\/tr>\n\n\n\n
      A<\/td>\n900 \u5143<\/td>\n<\/tr>\n
      B<\/td>\n500 \u5143<\/td>\n<\/tr>\n
      \u603b\u4f59\u989d<\/td>\n1400 \u5143<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

      \u539f\u672c\u5e94\u8be5\u4fdd\u6301\u4e0d\u53d8\u7684\u603b\u4f59\u989d\u51cf\u5c11\u4e86 100 \u5143，\u663e\u7136\u4e0d\u7b26\u5408\u8f6c\u8d26\u4e1a\u52a1\u7684\u8981\u6c42\u3002<\/p>\n

      \u5728\u5b9e\u9645\u5e94\u7528\u4e2d，\u6570\u636e\u5e93\u64cd\u4f5c\u53ef\u80fd\u53d7\u5230\u7a0b\u5e8f\u5f02\u5e38\u3001\u6570\u636e\u5e93\u8fde\u63a5\u4e2d\u65ad\u3001\u670d\u52a1\u5668\u6545\u969c\u7b49\u56e0\u7d20\u7684\u5f71\u54cd\u3002\u5982\u679c\u591a\u4e2a\u64cd\u4f5c\u4e4b\u95f4\u7f3a\u4e4f\u6709\u6548\u7684\u4e8b\u52a1\u7ba1\u7406，\u5c31\u53ef\u80fd\u51fa\u73b0\u53ea\u5b8c\u6210\u90e8\u5206\u64cd\u4f5c\u7684\u60c5\u51b5\u3002<\/p>\n

      \u4e8b\u52a1\u7684\u4f5c\u7528，\u5c31\u662f\u5c06\u8fd9\u4e9b\u76f8\u5173\u64cd\u4f5c\u4f5c\u4e3a\u4e00\u4e2a\u6574\u4f53\u8fdb\u884c\u7ba1\u7406，\u5c3d\u53ef\u80fd\u907f\u514d\u90e8\u5206\u64cd\u4f5c\u6210\u529f\u3001\u90e8\u5206\u64cd\u4f5c\u5931\u8d25\u6240\u9020\u6210\u7684\u6570\u636e\u4e0d\u4e00\u81f4\u95ee\u9898\u3002<\/span><\/p>\n

      \u56e0\u6b64，\u4e8b\u52a1\u7279\u522b\u9002\u7528\u4e8e\u4ee5\u4e0b\u573a\u666f：<\/p>\n

        \n
      • \n

        \u94f6\u884c\u8f6c\u8d26： \u6263\u6b3e\u4e0e\u5165\u8d26\u5fc5\u987b\u76f8\u4e92\u914d\u5408\u3002<\/p>\n<\/li>\n

      • \n

        \u8ba2\u5355\u5904\u7406： \u521b\u5efa\u8ba2\u5355\u3001\u6263\u51cf\u5e93\u5b58\u7b49\u64cd\u4f5c\u9700\u8981\u534f\u8c03\u6267\u884c\u3002<\/p>\n<\/li>\n

      • \n

        \u8d26\u6237\u4f59\u989d\u53d8\u66f4： \u8f6c\u8d26\u3001\u5145\u503c\u3001\u9000\u6b3e\u7b49\u64cd\u4f5c\u9700\u8981\u4fdd\u8bc1\u6570\u636e\u6b63\u786e\u3002<\/p>\n<\/li>\n

      • \n

        \u4e1a\u52a1\u6570\u636e\u66f4\u65b0： \u591a\u5f20\u6570\u636e\u8868\u4e4b\u95f4\u7684\u4fee\u6539\u9700\u8981\u6ee1\u8db3\u7edf\u4e00\u7684\u4e1a\u52a1\u89c4\u5219\u3002<\/p>\n<\/li>\n<\/ul>\n

        \u9700\u8981\u8bf4\u660e\u7684\u662f，\u4e8b\u52a1\u4e3b\u8981\u8d1f\u8d23\u4fdd\u8bc1\u4e8b\u52a1\u64cd\u4f5c\u7684\u539f\u5b50\u6027\u3001\u9694\u79bb\u6027\u7b49\u5c5e\u6027，\u5e76\u4e0d\u80fd\u81ea\u52a8\u4fdd\u8bc1\u6240\u6709\u4e1a\u52a1\u903b\u8f91\u90fd\u6b63\u786e\u3002\u4f8b\u5982，\u5982\u679c\u7a0b\u5e8f\u672c\u8eab\u8ba1\u7b97\u51fa\u4e86\u9519\u8bef\u7684\u8f6c\u8d26\u91d1\u989d，\u4e8b\u52a1\u4e5f\u4e0d\u4f1a\u81ea\u52a8\u7ea0\u6b63\u8fd9\u4e2a\u9519\u8bef\u3002<\/p>\n

        1.3 \u4e8b\u52a1\u7684\u56db\u5927\u7279\u6027（ACID）<\/h3>\n

        \u4e3a\u4e86\u4fdd\u8bc1\u4e8b\u52a1\u80fd\u591f\u6b63\u786e\u6267\u884c，\u6570\u636e\u5e93\u4e8b\u52a1\u901a\u5e38\u5177\u6709\u56db\u4e2a\u91cd\u8981\u7279\u6027，\u5206\u522b\u662f\u539f\u5b50\u6027（Atomicity）\u3001\u4e00\u81f4\u6027（Consistency）\u3001\u9694\u79bb\u6027（Isolation）\u548c\u6301\u4e45\u6027（Durability），\u5408\u79f0 ACID\u3002<\/p>\n

        1.3.1 \u539f\u5b50\u6027（Atomicity）<\/h4>\n

        \u539f\u5b50\u6027\u6307\u7684\u662f：\u4e8b\u52a1\u4e2d\u7684\u64cd\u4f5c\u8981\u4e48\u5168\u90e8\u5b8c\u6210，\u8981\u4e48\u5168\u90e8\u4e0d\u751f\u6548，\u4e0d\u5b58\u5728\u53ea\u6210\u529f\u4e00\u90e8\u5206\u7684\u6700\u7ec8\u7ed3\u679c\u3002<\/p>\n

        \u7ee7\u7eed\u4ee5\u94f6\u884c\u8f6c\u8d26\u4e3a\u4f8b，\u6263\u6b3e\u548c\u5165\u8d26\u5c5e\u4e8e\u540c\u4e00\u4e2a\u4e8b\u52a1\u3002<\/p>\n

        \u5982\u679c\u4e24\u4e2a\u64cd\u4f5c\u90fd\u6210\u529f\u6267\u884c，\u90a3\u4e48\u4e8b\u52a1\u53ef\u4ee5\u6b63\u5e38\u63d0\u4ea4；\u5982\u679c\u5176\u4e2d\u4e00\u4e2a\u64cd\u4f5c\u53d1\u751f\u5f02\u5e38，\u4e8b\u52a1\u53ef\u4ee5\u56de\u6eda，\u64a4\u9500\u672c\u6b21\u4e8b\u52a1\u4e2d\u5df2\u7ecf\u6267\u884c\u4f46\u5c1a\u672a\u63d0\u4ea4\u7684\u4fee\u6539\u3002<\/p>\n

        \u8fd9\u6837\u5c31\u53ef\u4ee5\u907f\u514d\u53ea\u6263\u6b3e\u3001\u4e0d\u5165\u8d26\u7684\u60c5\u51b5\u3002<\/p>\n

        \u5728 MySQL \u7684 InnoDB \u5b58\u50a8\u5f15\u64ce\u4e2d，\u539f\u5b50\u6027\u4e3b\u8981\u4f9d\u9760 Undo Log \u7b49\u673a\u5236\u5b9e\u73b0\u3002\u5f53\u4e8b\u52a1\u9700\u8981\u56de\u6eda\u65f6，\u6570\u636e\u5e93\u53ef\u4ee5\u5229\u7528\u76f8\u5173\u4fe1\u606f\u64a4\u9500\u4e8b\u52a1\u6240\u505a\u7684\u4fee\u6539\u3002<\/p>\n

        1.3.2 \u4e00\u81f4\u6027（Consistency）<\/h4>\n

        \u4e00\u81f4\u6027\u6307\u7684\u662f：\u4e8b\u52a1\u6267\u884c\u524d\u540e，\u6570\u636e\u5e93\u90fd\u5e94\u8be5\u6ee1\u8db3\u76f8\u5e94\u7684\u5b8c\u6574\u6027\u7ea6\u675f\u548c\u4e1a\u52a1\u89c4\u5219\u3002<\/p>\n

        \u4f8b\u5982，\u5728\u94f6\u884c\u8f6c\u8d26\u4e1a\u52a1\u4e2d，\u5982\u679c\u6211\u4eec\u89c4\u5b9a\u8d26\u6237\u4f59\u989d\u4e0d\u80fd\u4e3a\u8d1f\u6570，\u90a3\u4e48\u6bcf\u6b21\u8f6c\u8d26\u64cd\u4f5c\u5b8c\u6210\u540e，\u90fd\u5e94\u8be5\u6ee1\u8db3\u8fd9\u4e00\u89c4\u5219\u3002<\/p>\n

        \u5bf9\u4e8e\u524d\u9762\u4ecb\u7ecd\u7684 A \u5411 B \u8f6c\u8d26 100 \u5143\u7684\u4e1a\u52a1，\u5728\u6b63\u5e38\u8f6c\u8d26\u4e14\u4e0d\u8003\u8651\u5176\u4ed6\u5e76\u53d1\u8d44\u91d1\u53d8\u52a8\u7684\u60c5\u51b5\u4e0b，\u4e24\u4e2a\u8d26\u6237\u7684\u603b\u4f59\u989d\u5e94\u5f53\u4fdd\u6301\u4e0d\u53d8\u3002<\/p>\n

        \u4e8b\u52a1\u6267\u884c\u524d，\u4e24\u4e2a\u8d26\u6237\u7684\u603b\u4f59\u989d\u4e3a 1500 \u5143；\u4e8b\u52a1\u6b63\u5e38\u5b8c\u6210\u540e，\u603b\u4f59\u989d\u4ecd\u7136\u4e3a 1500 \u5143\u3002<\/p>\n

        \u8fd9\u5c31\u662f\u8be5\u4e1a\u52a1\u9700\u8981\u6ee1\u8db3\u7684\u4e00\u81f4\u6027\u8981\u6c42\u3002<\/p>\n

        \u9700\u8981\u6ce8\u610f，\u4e00\u81f4\u6027\u5e76\u4e0d\u662f\u4ec5\u4ec5\u4f9d\u9760\u4e8b\u52a1\u5c31\u80fd\u81ea\u52a8\u5b9e\u73b0\u7684\u3002\u5b83\u8fd8\u4f9d\u8d56\u4e8e\u6b63\u786e\u7684\u4e1a\u52a1\u903b\u8f91\u3001\u6570\u636e\u5e93\u7ea6\u675f\u4ee5\u53ca\u539f\u5b50\u6027\u3001\u9694\u79bb\u6027\u548c\u6301\u4e45\u6027\u7b49\u7279\u6027\u7684\u5171\u540c\u4fdd\u969c\u3002<\/p>\n

        \u4f8b\u5982，\u5982\u679c\u7a0b\u5e8f\u5141\u8bb8\u7528\u6237\u8f6c\u8d26\u8d85\u8fc7\u8d26\u6237\u4f59\u989d\u7684\u91d1\u989d，\u90a3\u4e48\u5373\u4f7f\u6574\u4e2a\u4e8b\u52a1\u6210\u529f\u63d0\u4ea4，\u4e5f\u53ef\u80fd\u8fdd\u53cd\u4e1a\u52a1\u89c4\u5219\u3002\u56e0\u6b64，\u7a0b\u5e8f\u4ecd\u7136\u9700\u8981\u5bf9\u4f59\u989d\u8fdb\u884c\u5408\u7406\u6821\u9a8c\u3002<\/p>\n

        1.3.3 \u9694\u79bb\u6027（Isolation）<\/h4>\n

        \u9694\u79bb\u6027\u6307\u7684\u662f：\u591a\u4e2a\u4e8b\u52a1\u5e76\u53d1\u6267\u884c\u65f6，\u4e00\u4e2a\u4e8b\u52a1\u7684\u6267\u884c\u4e0d\u5e94\u8be5\u53d7\u5230\u5176\u4ed6\u4e8b\u52a1\u4e0d\u5408\u7406\u7684\u5e72\u6270\u3002<\/p>\n

        \u5047\u8bbe\u4e24\u4e2a\u4e8b\u52a1\u540c\u65f6\u8bfb\u53d6\u540c\u4e00\u4e2a\u8d26\u6237\u7684\u4f59\u989d，\u5e76\u6839\u636e\u8bfb\u53d6\u7ed3\u679c\u8fdb\u884c\u4fee\u6539\u3002\u5982\u679c\u7f3a\u4e4f\u9002\u5f53\u7684\u5e76\u53d1\u63a7\u5236，\u5c31\u53ef\u80fd\u51fa\u73b0\u76f8\u4e92\u8986\u76d6\u4fee\u6539\u7ed3\u679c\u7b49\u95ee\u9898\u3002<\/p>\n

        \u4f8b\u5982，\u8d26\u6237\u4f59\u989d\u4e3a 1000 \u5143，\u4e24\u4e2a\u4e8b\u52a1\u5206\u522b\u51c6\u5907\u6263\u9664 100 \u5143\u548c 200 \u5143\u3002\u5982\u679c\u4e24\u4e2a\u4e8b\u52a1\u90fd\u57fa\u4e8e\u6700\u521d\u8bfb\u53d6\u7684\u4f59\u989d\u8fdb\u884c\u8ba1\u7b97，\u5e76\u4e14\u540e\u5199\u5165\u7684\u7ed3\u679c\u8986\u76d6\u4e86\u5148\u5199\u5165\u7684\u7ed3\u679c，\u90a3\u4e48\u6700\u7ec8\u4f59\u989d\u5c31\u53ef\u80fd\u4e0d\u7b26\u5408\u9884\u671f\u3002<\/p>\n

        \u4e3a\u4e86\u63a7\u5236\u5e76\u53d1\u4e8b\u52a1\u4e4b\u95f4\u7684\u76f8\u4e92\u5f71\u54cd，MySQL \u63d0\u4f9b\u4e86\u4e0d\u540c\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b，\u4f8b\u5982\u8bfb\u672a\u63d0\u4ea4\u3001\u8bfb\u5df2\u63d0\u4ea4\u3001\u53ef\u91cd\u590d\u8bfb\u548c\u4e32\u884c\u5316<\/span>\u3002<\/p>\n

        \u4e0d\u540c\u9694\u79bb\u7ea7\u522b\u5bf9\u5e76\u53d1\u4e8b\u52a1\u7684\u9650\u5236\u7a0b\u5ea6\u4e0d\u540c，\u80fd\u591f\u907f\u514d\u7684\u95ee\u9898\u4e5f\u6709\u6240\u533a\u522b\u3002<\/p>\n

        \u540e\u7eed\u7ae0\u8282\u5c06\u8be6\u7ec6\u4ecb\u7ecd\u810f\u8bfb\u3001\u4e0d\u53ef\u91cd\u590d\u8bfb\u3001\u5e7b\u8bfb\u7b49\u5e76\u53d1\u95ee\u9898，\u4ee5\u53ca MySQL \u5982\u4f55\u901a\u8fc7 MVCC \u548c\u9501\u673a\u5236\u5b9e\u73b0\u4e8b\u52a1\u9694\u79bb\u3002<\/p>\n

        1.3.4 \u6301\u4e45\u6027（Durability）<\/h4>\n

        \u6301\u4e45\u6027\u6307\u7684\u662f：\u4e8b\u52a1\u4e00\u65e6\u6210\u529f\u63d0\u4ea4，\u5176\u4fee\u6539\u7ed3\u679c\u5c31\u5e94\u8be5\u5f97\u5230\u6301\u4e45\u4fdd\u5b58，\u5373\u4f7f\u6570\u636e\u5e93\u968f\u540e\u53d1\u751f\u6545\u969c，\u4e5f\u5e94\u8be5\u80fd\u591f\u901a\u8fc7\u6062\u590d\u673a\u5236\u4fdd\u8bc1\u5df2\u63d0\u4ea4\u4e8b\u52a1\u7684\u7ed3\u679c\u3002<\/p>\n

        \u4f8b\u5982，\u7528\u6237 A \u5411\u7528\u6237 B \u8f6c\u8d26 100 \u5143，\u6570\u636e\u5e93\u5df2\u7ecf\u6210\u529f\u63d0\u4ea4\u4e8b\u52a1\u3002\u5982\u679c\u6b64\u65f6\u670d\u52a1\u5668\u7a81\u7136\u65ad\u7535，\u90a3\u4e48\u5728\u6570\u636e\u5e93\u6062\u590d\u4e4b\u540e，\u8fd9\u7b14\u5df2\u7ecf\u63d0\u4ea4\u7684\u8f6c\u8d26\u4ecd\u7136\u5e94\u8be5\u5f97\u5230\u4fdd\u7559\u3002<\/p>\n

        \u5728 MySQL \u7684 InnoDB \u5b58\u50a8\u5f15\u64ce\u4e2d，Redo Log \u662f\u4fdd\u969c\u4e8b\u52a1\u6301\u4e45\u6027\u7684\u91cd\u8981\u673a\u5236\u3002\u6570\u636e\u5e93\u53ef\u4ee5\u5229\u7528\u76f8\u5173\u65e5\u5fd7\u4fe1\u606f，\u5728\u53d1\u751f\u6545\u969c\u540e\u6062\u590d\u5df2\u7ecf\u63d0\u4ea4\u4f46\u5c1a\u672a\u5b8c\u5168\u5199\u5165\u6570\u636e\u6587\u4ef6\u7684\u4fee\u6539\u3002<\/p>\n

        \u5f53\u7136，\u6301\u4e45\u6027\u4f9d\u8d56\u4e8e\u6570\u636e\u5e93\u7684\u65e5\u5fd7\u914d\u7f6e\u3001\u5b58\u50a8\u8bbe\u5907\u4ee5\u53ca\u6545\u969c\u6062\u590d\u673a\u5236\u7b49\u6761\u4ef6，\u5e76\u4e0d\u610f\u5473\u7740\u4efb\u4f55\u786c\u4ef6\u635f\u574f\u6216\u6240\u6709\u707e\u96be\u573a\u666f\u4e0b\u90fd\u7edd\u5bf9\u4e0d\u4f1a\u4e22\u5931\u6570\u636e\u3002<\/p>\n

        \u4e8c\u3001\u4e8b\u52a1\u7684\u57fa\u672c\u64cd\u4f5c<\/h2>\n

        2.1 MySQL \u7684\u81ea\u52a8\u63d0\u4ea4\u673a\u5236<\/h3>\n

        \u5728\u4f7f\u7528 MySQL \u6267\u884c SQL \u8bed\u53e5\u65f6，\u5927\u5bb6\u53ef\u80fd\u4f1a\u5b58\u5728\u4e00\u4e2a\u7591\u95ee：\u6211\u4eec\u5e76\u6ca1\u6709\u663e\u793a\u5f00\u542f\u4e8b\u52a1，\u4e3a\u4ec0\u4e48 INSERT\u3001UPDATE\u3001DELETE \u7b49\u8bed\u53e5\u4e4b\u540e，\u6570\u636e\u4f9d\u7136\u4f1a\u53d8\u5316？<\/p>\n

        \u8fd9\u662f\u56e0\u4e3a MySQL \u9ed8\u8ba4\u5f00\u542f\u81ea\u52a8\u63d0\u4ea4\u673a\u5236：\u5355\u6761 SQL \u8bed\u53e5\u4f1a\u88ab\u5f53\u6210\u4e00\u4e2a\u4e8b\u52a1<\/span><\/p>\n

        \u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b SQL \u8bed\u53e5\u6765\u67e5\u770b\u5f53\u524d\u4f1a\u8bdd\u7684\u81ea\u52a8\u63d0\u4ea4\u72b6\u6001：<\/p>\n

        mysql> select @@autocommit;
        \n+————–+
        \n| @@autocommit |
        \n+————–+
        \n| 1 |
        \n+————–+
        \n1 row in set (0.00 sec) <\/p>\n

        \u5176\u4e2d：1 \u8868\u793a\u5f00\u542f\u81ea\u52a8\u63d0\u4ea4\u00a0 0 \u8868\u793a\u5173\u95ed\u81ea\u52a8\u63d0\u4ea4<\/p>\n

        \u5f53\u81ea\u52a8\u63d0\u4ea4\u5f00\u542f\u65f6，\u6bcf\u6761\u72ec\u7acb\u7684 SQL \u8bed\u53e5\u4f1a\u4f5c\u4e3a\u4e00\u4e2a\u4e8b\u52a1\u6267\u884c，\u5e76\u5728\u8bed\u53e5\u6210\u529f\u6267\u884c\u540e\u81ea\u52a8\u63d0\u4ea4\u3002<\/p>\n

        \u6b64\u5916，\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u8bed\u53e5\u4fee\u6539\u5f53\u524d\u4f1a\u8bdd\u7684\u81ea\u52a8\u63d0\u4ea4\u8bbe\u7f6e：<\/p>\n

        mysql> select @@autocommit;
        \n+————–+
        \n| @@autocommit |
        \n+————–+
        \n| 1 |
        \n+————–+
        \n1 row in set (0.01 sec)<\/p>\n

        mysql> set autocommit = 0;
        \nQuery OK, 0 rows affected (0.00 sec)<\/p>\n

        mysql> select @@autocommit;
        \n+————–+
        \n| @@autocommit |
        \n+————–+
        \n| 0 |
        \n+————–+
        \n1 row in set (0.00 sec)<\/p>\n

        mysql> set autocommit = 1;
        \nQuery OK, 0 rows affected (0.00 sec)<\/p>\n

        mysql> select @@autocommit;
        \n+————–+
        \n| @@autocommit |
        \n+————–+
        \n| 1 |
        \n+————–+
        \n1 row in set (0.00 sec)<\/p>\n

        \u9700\u8981\u6ce8\u610f：set autocommit \u4fee\u6539\u7684\u662f\u5f53\u524d\u4f1a\u8bdd\u7684\u8bbe\u7f6e\u3002\u5173\u95ed\u81ea\u52a8\u63d0\u4ea4\u540e，SQL \u8bed\u53e5\u7684\u6570\u636e\u4fee\u6539，\u4e0d\u4f1a\u50cf\u9ed8\u8ba4\u6a21\u5f0f\u90a3\u6837\u81ea\u52a8\u63d0\u4ea4，\u9700\u8981\u624b\u52a8 COMMIT \u63d0\u4ea4\u4e8b\u52a1\u6216\u8005 ROLLBACK \u56de\u6eda\u4e8b\u52a1\u3002<\/p>\n

        2.2 \u5f00\u542f\u4e8b\u52a1<\/h3>\n

        \u5728\u5b9e\u9645\u4e1a\u52a1\u4e2d，\u5982\u679c\u4e00\u4e2a\u4e1a\u52a1\u9700\u8981\u6267\u884c\u591a\u6761 SQL \u8bed\u53e5，\u5e76\u4e14\u8981\u6c42\u8fd9\u4e9b SQL \u4f5c\u4e3a\u4e00\u4e2a\u6574\u4f53\u6210\u529f\u6216\u8005\u5931\u8d25，\u90a3\u4e48\u4ec5\u4f9d\u9760\u9ed8\u8ba4\u7684\u81ea\u52a8\u63d0\u4ea4\u673a\u5236\u5c31\u4e0d\u591f\u4e86\u3002\u6b64\u65f6\u6211\u4eec\u9700\u8981\u663e\u793a\u5f00\u542f\u4e8b\u52a1，\u5c06\u591a\u6761 SQL \u8bed\u53e5\u7ec4\u7ec7\u5728\u540c\u4e00\u4e2a\u4e8b\u52a1\u4e2d\u518d\u63d0\u4ea4\u3002<\/p>\n

        \u5728 MySQL \u4e2d，\u5e38\u89c1\u5f00\u542f\u4e8b\u52a1\u7684\u65b9\u5f0f\u6709\u4e24\u79cd：<\/p>\n

        start transaction;<\/p>\n

        begin; <\/p>\n

        \u4e8b\u52a1\u5f00\u542f\u4e4b\u540e，\u6211\u4eec\u5c31\u53ef\u4ee5\u5728\u5176\u4e2d\u6267\u884c\u591a\u6761 SQL \u8bed\u53e5\u3002\u8fd9\u4e9b\u8bed\u53e5\u7684\u4fee\u6539\u53ef\u4ee5\u5728\u4e8b\u52a1\u7ed3\u675f\u524d\u7edf\u4e00\u63d0\u4ea4，\u4e5f\u53ef\u4ee5\u901a\u8fc7\u56de\u6eda\u64a4\u9500\u3002<\/p>\n

        start transaction;<\/p>\n

        update account
        \nset balance = balance – 100
        \nWHERE id = 1;<\/p>\n

        update account
        \nset balance = balance + 100
        \nWHERE id = 2; <\/p>\n

        \u4e0a\u8ff0\u4ee3\u7801\u5f00\u542f\u4e86\u4e00\u4e2a\u4e8b\u52a1，\u5e76\u4f9d\u6b21\u6267\u884c\u4e24\u6761 SQL \u8bed\u53e5\u3002<\/p>\n

        \u6b64\u65f6，\u6211\u4eec\u8fd8\u6ca1\u6709\u63d0\u4ea4\u4e8b\u52a1，\u56e0\u6b64\u8fd9\u4e9b\u4fee\u6539\u5c1a\u672a\u901a\u8fc7\u4e8b\u52a1\u63d0\u4ea4\u6b63\u5f0f\u751f\u6548\u3002<\/p>\n

        \u9700\u8981\u6ce8\u610f\u7684\u662f，\u4e8b\u7269\u7684\u4fee\u6539\u5e76\u4e0d\u610f\u5473\u7740\u5176\u4ed6\u4e8b\u52a1\u5b8c\u5168\u770b\u4e0d\u5230\u6b64\u4e8b\u52a1\u505a\u51fa\u7684\u76f8\u5173\u6570\u636e\u53d8\u5316\u3002\u5176\u4ed6\u4e8b\u52a1\u80fd\u5426\u8bfb\u53d6\u5230\u8fd9\u4e9b\u4fee\u6539，\u53d6\u51b3\u4e8e\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u53ca\u5177\u4f53\u7684\u8bfb\u53d6\u65b9\u5f0f\u3002<\/p>\n

        \u53e6\u5916，\u4e8b\u52a1\u7684\u884c\u4e3a\u8fd8\u4e0e\u5b58\u50a8\u5f15\u64ce\u6709\u5173\u3002MySQL \u4e2d\u7684 InnoDB \u652f\u6301\u4e8b\u52a1，\u800c MyISAM \u4e0d\u652f\u6301\u4e8b\u52a1\u56de\u6eda\u7b49\u5b8c\u6574\u7684\u4e8b\u52a1\u7ba1\u7406\u80fd\u529b\u3002\u56e0\u6b64，\u5728\u5b9e\u9645\u4f7f\u7528\u4e8b\u52a1\u65f6，\u9700\u8981\u786e\u4fdd\u76f8\u5173\u6570\u636e\u8868\u4f7f\u7528\u652f\u6301\u4e8b\u52a1\u7684\u5b58\u50a8\u5f15\u64ce\u3002<\/p>\n

        2.3 \u63d0\u4ea4\u4e8b\u52a1<\/h3>\n

        \u4e8b\u52a1\u4e2d\u7684\u64cd\u4f5c\u6267\u884c\u5b8c\u6210，\u5e76\u4e14\u6ee1\u8db3\u4e1a\u52a1\u8981\u6c42\u548c\u9884\u671f\u7ed3\u679c\u65f6，\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528 COMMIT \u63d0\u4ea4\u4e8b\u52a1：<\/p>\n

        commit; <\/p>\n

        \u63d0\u4ea4\u4e8b\u52a1\u610f\u5473\u7740\u786e\u8ba4\u672c\u6b21\u4e8b\u52a1\u7684\u4fee\u6539，\u4f7f\u5176\u6309\u7167\u6570\u636e\u5e93\u7684\u4e8b\u52a1\u63d0\u4ea4\u673a\u5236\u6b63\u5f0f\u751f\u6548\u3002<\/p>\n

        start transaction;<\/p>\n

        update account
        \nset balance = balance – 100
        \nWHERE id = 1;<\/p>\n

        update account
        \nset balance = balance + 100
        \nWHERE id = 2;<\/p>\n

        commit; <\/p>\n

        \u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d，\u4e8b\u52a1\u4f9d\u6b21\u5b8c\u6210\u6263\u6b3e\u548c\u5165\u8d26\u64cd\u4f5c，\u6700\u540e\u901a\u8fc7 COMMIT \u63d0\u4ea4\u4e8b\u52a1\u3002\u5982\u679c\u4e24\u4e2a\u66f4\u65b0\u64cd\u4f5c\u90fd\u6267\u884c\u6210\u529f，\u5e76\u4e14\u6ee1\u8db3\u76f8\u5e94\u7684\u4e1a\u52a1\u6761\u4ef6，\u90a3\u4e48\u4e8b\u52a1\u5c31\u53ef\u4ee5\u6b63\u5e38\u63d0\u4ea4\u3002<\/p>\n

        \u5bf9\u4e8e InnoDB \u800c\u8a00，\u6210\u529f\u63d0\u4ea4\u7684\u4e8b\u52a1\u8fd8\u9700\u8981\u6ee1\u8db3\u6301\u4e45\u6027\u8981\u6c42，\u5373\u5728\u6570\u636e\u5e93\u6545\u969c\u6062\u590d\u540e，\u5df2\u63d0\u4ea4\u4e8b\u52a1\u7684\u4fee\u6539\u5e94\u5f53\u5f97\u5230\u4fdd\u7559\u3002<\/p>\n

        \u56e0\u6b64，COMMIT \u53ef\u4ee5\u7406\u89e3\u4e3a：\u786e\u8ba4\u5f53\u524d\u4e8b\u52a1\u7684\u4fee\u6539，\u5e76\u7ed3\u675f\u5f53\u524d\u4e8b\u52a1\u3002<\/p>\n

        2.4 \u56de\u6eda\u4e8b\u52a1<\/p>\n

        \u5982\u679c\u4e8b\u52a1\u6267\u884c\u8fc7\u7a0b\u4e2d\u53d1\u73b0\u5f02\u5e38\u6216\u8005\u67d0\u4e9b\u64cd\u4f5c\u4e0d\u6ee1\u8db3\u4e1a\u52a1，\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528 ROLLBACK \u56de\u6eda\u4e8b\u52a1\u3002<\/p>\n

        rollback; <\/p>\n

        \u56de\u6eda\u64cd\u4f5c\u4f1a\u76f4\u63a5\u64a4\u9500\u5f53\u524d\u4e8b\u52a1\u5c1a\u672a\u63d0\u4ea4\u7684\u4fee\u6539，\u5e76\u7ed3\u675f\u5f53\u524d\u4e8b\u52a1\u3002<\/p>\n

        begin;<\/p>\n

        update account
        \nset balance = balance – 100
        \nwhere id = 1;<\/p>\n

        — \u67e5\u770b\u4fee\u6539\u540e\u7684\u4f59\u989d
        \nSELECT * FROM account where id = 1;<\/p>\n

        — \u64a4\u9500\u672c\u6b21\u4e8b\u52a1\u7684\u4fee\u6539
        \nrollback;<\/p>\n

        — \u518d\u6b21\u67e5\u770b\u4f59\u989d
        \nSELECT * FROM account where id = 1; <\/p>\n

        \u5047\u8bbe\u8d26\u6237 A \u539f\u6765\u7684\u4f59\u989d\u4e3a 1000 \u5143，\u90a3\u4e48\u6267\u884c UPDATE \u4e4b\u540e，\u5728\u5f53\u524d\u4e8b\u52a1\u4e2d\u67e5\u8be2\u5230\u7684\u4f59\u989d\u4e3a 900 \u5143\u3002\u4f46\u662f，\u7531\u4e8e\u6211\u4eec\u6267\u884c\u4e86 ROLLBACK，\u8fd9\u6b21\u4fee\u6539\u4f1a\u88ab\u64a4\u9500\u3002\u518d\u6b21\u67e5\u8be2\u65f6，\u8d26\u6237\u4f59\u989d\u5c06\u6062\u590d\u4e3a\u4e8b\u52a1\u5f00\u59cb\u524d\u7684 1000 \u5143\u3002<\/p>\n

        \u9700\u8981\u6ce8\u610f\u7684\u662f：\u5e76\u4e0d\u662f\u4efb\u4f55\u4e00\u6761 SQL \u6267\u884c\u5931\u8d25，MySQL \u4f1a\u56de\u6eda\u4e8b\u52a1\u3002MySQL \u56de\u6eda\u4e8b\u52a1\u662f\u4f7f\u7528\u8005\u8fdb\u884c ROLLBACK \u6216\u8005\u8be5\u4e8b\u52a1\u672a\u88ab COMMIT \u624d\u4f1a\u56de\u6eda\u3002\u5f53\u4e8b\u52a1\u4e2d，\u51fa\u73b0 SQL \u8bed\u53e5\u7684\u6267\u884c\u5931\u8d25\u65f6，\u4f8b\u5982：\u8bed\u6cd5\u9519\u8bef\u7b49，MySQL \u5e76\u4e0d\u4f1a\u8fdb\u884c\u81ea\u52a8\u56de\u6eda\u4e8b\u52a1\u3002<\/p>\n

        2.5 \u4fdd\u5b58\u70b9\u00a0<\/h3>\n

        ROLLBACK \u901a\u5e38\u7528\u4e8e\u56de\u6eda\u6574\u4e2a\u5c1a\u672a\u63d0\u4ea4\u7684\u4e8b\u52a1，COMMIT \u7528\u4e8e\u63d0\u4ea4\u4e8b\u52a1\u3002\u90a3\u4e48\u5982\u679c\u4e00\u4e2a\u4e8b\u52a1\u5305\u542b\u591a\u4e2a\u64cd\u4f5c，\u6211\u4eec\u53ea\u60f3\u64a4\u9500\u4e00\u90e8\u5206\u64cd\u4f5c，\u800c\u4fdd\u7559\u4e4b\u524d\u5df2\u7ecf\u5b8c\u6210\u7684\u64cd\u4f5c，\u6b64\u65f6\u5c31\u9700\u8981\u4f7f\u7528\u4fdd\u5b58\u70b9\u3002<\/p>\n

        \u4fdd\u5b58\u70b9\u53ef\u4ee5\u5728\u4e8b\u52a1\u6267\u884c\u8fc7\u7a0b\u4e2d\u8bbe\u7f6e\u4e00\u4e2a\u56de\u6eda\u4f4d\u7f6e，\u4f7f\u6211\u4eec\u80fd\u591f\u5c06\u4e8b\u52a1\u56de\u6eda\u5230\u6307\u5b9a\u4f4d\u7f6e，\u800c\u4e0d\u5fc5\u76f4\u63a5\u64a4\u9500\u6574\u4e2a\u4e8b\u52a1\u3002<\/p>\n

        begin;<\/p>\n

        update account
        \nset balance = balance – 100
        \nwhere id = 1;<\/p>\n

        — \u521b\u5efa\u4fdd\u5b58\u70b9
        \nsavepoint sp1;<\/p>\n

        update account
        \nset balance = balance + 100
        \nwhere id = 2;<\/p>\n

        — \u64a4\u9500\u4fdd\u5b58\u70b9\u4e4b\u540e\u7684\u4fee\u6539
        \nrollback to savepoint sp1;<\/p>\n

        — \u6700\u7ec8\u64a4\u9500\u6574\u4e2a\u4e8b\u52a1
        \nrollback; <\/p>\n

        \u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d：<\/p>\n

      • \n

        \u9996\u5148\u5f00\u542f\u4e8b\u52a1，\u5e76\u5c06\u8d26\u6237 A \u7684\u4f59\u989d\u51cf\u5c11 100 \u5143\u3002<\/p>\n<\/li>\n

      • \n

        \u521b\u5efa\u4fdd\u5b58\u70b9 sp1，\u8bb0\u5f55\u5f53\u524d\u4e8b\u52a1\u7684\u56de\u6eda\u4f4d\u7f6e\u3002<\/p>\n<\/li>\n

      • \n

        \u5c06\u8d26\u6237 B \u7684\u4f59\u989d\u589e\u52a0 100 \u5143\u3002<\/p>\n<\/li>\n

      • \n

        \u6267\u884c rollback to savepoint sp1，\u64a4\u9500\u4fdd\u5b58\u70b9\u4e4b\u540e\u7684\u4fee\u6539，\u4f46\u4fdd\u7559\u4fdd\u5b58\u70b9\u4e4b\u524d\u7684\u4fee\u6539\u3002<\/p>\n<\/li>\n

      • \n

        \u6700\u540e\u6267\u884c rollback，\u64a4\u9500\u6574\u4e2a\u4e8b\u52a1\u4e2d\u7684\u5269\u4f59\u4fee\u6539\u3002<\/p>\n<\/li>\n

        \u8fd9\u91cc\u7684\u8f6c\u8d26\u64cd\u4f5c\u4ec5\u7528\u4e8e\u6f14\u793a\u4fdd\u5b58\u70b9\u7684\u8bed\u6cd5，\u5b9e\u9645\u4e1a\u52a1\u4e2d\u4e0d\u80fd\u5c06\u53ea\u5b8c\u6210\u4e00\u534a\u7684\u8f6c\u8d26\u64cd\u4f5c\u63d0\u4ea4\u3002<\/p>\n

        \u9700\u8981\u6ce8\u610f，ROLLBACK TO SAVEPOINT\u00a0\u5e76\u4e0d\u4f1a\u7ed3\u675f\u6574\u4e2a\u4e8b\u52a1，\u800c\u666e\u901a\u7684 ROLLBACK \u4f1a\u56de\u6eda\u6574\u4e2a\u4e8b\u52a1\u5e76\u7ed3\u675f\u5b83\u3002\u53e6\u5916，\u4fdd\u5b58\u70b9\u53ea\u662f\u4e8b\u52a1\u5185\u90e8\u7684\u56de\u6eda\u6807\u8bb0，\u5e76\u4e0d\u662f\u4e00\u6b21\u72ec\u7acb\u63d0\u4ea4\u3002\u5373\u4f7f\u5df2\u7ecf\u521b\u5efa\u4fdd\u5b58\u70b9，\u4e8b\u52a1\u6700\u7ec8\u4ecd\u7136\u53ef\u4ee5\u6574\u4f53\u56de\u6eda\u3002\u00a0<\/p>\n

        2.6 \u5b9e\u6218：\u6a21\u62df\u94f6\u884c\u8f6c\u8d26<\/h3>\n

        \u7406\u89e3\u4e86\u4e8b\u52a1\u7684\u57fa\u672c\u64cd\u4f5c\u4e4b\u540e，\u6211\u4eec\u901a\u8fc7\u4e00\u4e2a\u5b8c\u6574\u6848\u4f8b，\u5c06\u524d\u9762\u4ecb\u7ecd\u7684\u77e5\u8bc6\u4e32\u8054\u8d77\u6765\u3002<\/p>\n

        \u5047\u8bbe\u5b58\u5728\u4e00\u5f20\u8d26\u6237\u8868 account，\u5176\u4e2d\u5305\u542b\u8d26\u6237\u7f16\u53f7\u3001\u8d26\u6237\u540d\u79f0\u548c\u8d26\u6237\u4f59\u989d\u3002<\/p>\n

        2.6.1 \u521b\u5efa\u6d4b\u8bd5\u6570\u636e<\/h4>\n

        \u9996\u5148\u521b\u5efa\u8d26\u6237\u8868：<\/p>\n

        CREATE TABLE account (
        \n id INT PRIMARY KEY,
        \n name VARCHAR(20) NOT NULL,
        \n balance DECIMAL(10, 2) NOT NULL
        \n) ENGINE = InnoDB; <\/p>\n

        \u7136\u540e\u63d2\u5165\u4e24\u6761\u6d4b\u8bd5\u6570\u636e：<\/p>\n

        INSERT INTO account (id, name, balance)
        \nVALUES
        \n (1, 'A', 1000.00),
        \n (2, 'B', 500.00); <\/p>\n

        \u67e5\u8be2\u521d\u59cb\u6570\u636e：<\/p>\n

        SELECT * FROM account; <\/p>\n

        \u7ed3\u679c\u5982\u4e0b：<\/p>\n\n\nidnamebalance<\/tr>\n\n\n
        1<\/td>\nA<\/td>\n1000.00<\/td>\n<\/tr>\n
        2<\/td>\nB<\/td>\n500.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        \u73b0\u5728，\u6211\u4eec\u8ba9\u8d26\u6237 A \u5411\u8d26\u6237 B \u8f6c\u8d26 100 \u5143\u3002<\/p>\n

        2.6.2 \u6267\u884c\u8f6c\u8d26\u4e8b\u52a1<\/h4>\n

        START TRANSACTION;<\/p>\n

        — A \u8d26\u6237\u6263\u6b3e
        \nUPDATE account
        \nSET balance = balance – 100
        \nWHERE id = 1 AND balance >= 100;<\/p>\n

        — B \u8d26\u6237\u5165\u8d26
        \nUPDATE account
        \nSET balance = balance + 100
        \nWHERE id = 2;<\/p>\n

        — \u786e\u8ba4\u64cd\u4f5c\u7ed3\u679c\u6ee1\u8db3\u4e1a\u52a1\u8981\u6c42\u540e\u63d0\u4ea4
        \nCOMMIT; <\/p>\n

        \u6267\u884c\u5b8c\u6210\u540e，\u518d\u6b21\u67e5\u8be2\u8d26\u6237\u6570\u636e：<\/p>\n

        SELECT * FROM account; <\/p>\n

        \u7ed3\u679c\u5982\u4e0b：<\/p>\n\n\nidnamebalance<\/tr>\n\n\n
        1<\/td>\nA<\/td>\n900.00<\/td>\n<\/tr>\n
        2<\/td>\nB<\/td>\n600.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        \u53ef\u4ee5\u770b\u5230，A \u7684\u4f59\u989d\u51cf\u5c11\u4e86 100 \u5143，B \u7684\u4f59\u989d\u589e\u52a0\u4e86 100 \u5143，\u4e24\u4e2a\u8d26\u6237\u7684\u603b\u4f59\u989d\u4f9d\u7136\u662f 1500 \u5143\u3002\u901a\u8fc7\u663e\u5f0f\u4e8b\u52a1，\u6211\u4eec\u5c06\u6263\u6b3e\u548c\u5165\u8d26\u4e24\u4e2a\u64cd\u4f5c\u7ec4\u7ec7\u5728\u4e00\u8d77，\u907f\u514d\u5b83\u4eec\u5728\u9ed8\u8ba4\u81ea\u52a8\u63d0\u4ea4\u6a21\u5f0f\u4e0b\u88ab\u5206\u522b\u63d0\u4ea4\u3002\u4e0d\u8fc7，\u4e0a\u8ff0 SQL \u793a\u4f8b\u4e3a\u4e86\u5c55\u793a\u4e8b\u52a1\u7684\u57fa\u672c\u7528\u6cd5，\u7701\u7565\u4e86\u5b8c\u6574\u7684\u4e1a\u52a1\u6821\u9a8c\u3002\u5728\u771f\u5b9e\u9879\u76ee\u4e2d，\u7a0b\u5e8f\u8fd8\u5e94\u8be5\u68c0\u67e5\u6263\u6b3e\u548c\u5165\u8d26\u8bed\u53e5\u662f\u5426\u5f71\u54cd\u4e86\u9884\u671f\u7684\u8bb0\u5f55\u6570，\u5e76\u5728\u4efb\u4e00\u64cd\u4f5c\u5931\u8d25\u6216\u4e1a\u52a1\u6761\u4ef6\u4e0d\u6ee1\u8db3\u65f6\u56de\u6eda\u6574\u4e2a\u4e8b\u52a1\u3002\u5426\u5219，\u5373\u4f7f\u4f7f\u7528\u4e86\u4e8b\u52a1，\u4e5f\u4e0d\u80fd\u4fdd\u8bc1\u4e1a\u52a1\u903b\u8f91\u4e00\u5b9a\u6b63\u786e\u3002<\/p>\n

        2.6.3 \u9a8c\u8bc1\u4e8b\u52a1\u56de\u6eda<\/h4>\n

        \u63a5\u4e0b\u6765，\u6211\u4eec\u518d\u6a21\u62df\u4e00\u6b21\u5931\u8d25\u7684\u8f6c\u8d26\u64cd\u4f5c\u3002<\/p>\n

        START TRANSACTION;<\/p>\n

        UPDATE account
        \nSET balance = balance – 100
        \nWHERE id = 1;<\/p>\n

        — \u5047\u8bbe\u6b64\u65f6\u53d1\u73b0\u4e1a\u52a1\u6761\u4ef6\u4e0d\u6ee1\u8db3
        \nROLLBACK; <\/p>\n

        \u518d\u6b21\u67e5\u8be2\u8d26\u6237\u6570\u636e：<\/p>\n

        SELECT * FROM account; <\/p>\n

        \u5982\u679c\u8fd9\u671f\u95f4\u6ca1\u6709\u5176\u4ed6\u4e8b\u52a1\u4fee\u6539\u8d26\u6237\u6570\u636e，\u90a3\u4e48\u67e5\u8be2\u7ed3\u679c\u4ecd\u7136\u662f：<\/p>\n\n\nidnamebalance<\/tr>\n\n\n
        1<\/td>\nA<\/td>\n900.00<\/td>\n<\/tr>\n
        2<\/td>\nB<\/td>\n600.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        \u8fd9\u662f\u56e0\u4e3a\u672c\u6b21\u4e8b\u52a1\u7684\u6263\u6b3e\u64cd\u4f5c\u5e76\u6ca1\u6709\u63d0\u4ea4，\u800c\u662f\u901a\u8fc7 ROLLBACK \u64a4\u9500\u4e86\u3002<\/p>\n

        \u4e09\u3001\u5e76\u53d1\u4e8b\u52a1\u5e26\u6765\u7684\u95ee\u9898<\/h2>\n

        \u5728\u4e0a\u4e00\u7ae0\u4e2d，\u6211\u4eec\u8be6\u7ec6\u4ecb\u7ecd\u4e86 MySQL \u4e8b\u52a1\u7684\u57fa\u672c\u64cd\u4f5c，\u5305\u62ec\u4e8b\u7269\u7684\u5f00\u542f\u3001\u63d0\u4ea4\u3001\u56de\u6eda\u4ee5\u53ca\u4fdd\u5b58\u70b9\u3002\u4f46\u662f，\u5728\u5b9e\u9645\u4e1a\u52a1\u4e2d，\u5f80\u5f80\u4f1a\u6709\u591a\u4e2a\u7528\u6237\u540c\u65f6\u8bbf\u95ee\u6570\u636e\u5e93\u3002\u5982\u679c\u591a\u4e2a\u4e8b\u52a1\u540c\u65f6\u6267\u884c，\u90a3\u4e48\u5b83\u4eec\u4e4b\u95f4\u53ef\u80fd\u76f8\u4e92\u5f71\u54cd，\u4ea7\u751f\u5e76\u53d1\u95ee\u9898\u3002<\/p>\n

        3.1\u00a0\u810f\u8bfb<\/h3>\n

        \u810f\u8bfb\u662f\u6307\u4e00\u4e2a\u4e8b\u52a1\u8bfb\u53d6\u5230\u4e86\u53e6\u4e00\u4e2a\u4e8b\u52a1\u5c1a\u672a\u63d0\u4ea4<\/span>\u7684\u6570\u636e\u3002<\/p>\n

        \u4e86\u89e3：\u4e3a\u4ec0\u4e48\u88ab\u79f0\u4e3a \u201c\u810f\u201d \u8bfb\u5462？<\/p>\n

        \u56e0\u4e3a\u53e6\u4e00\u4e2a\u4e8b\u52a1\u5c1a\u672a\u63d0\u4ea4，\u5176\u4fee\u6539\u7ed3\u679c\u6700\u7ec8\u53ef\u80fd\u88ab\u56de\u6eda\u3002\u5982\u679c\u5f53\u524d\u4e8b\u52a1\u8bfb\u53d6\u4e86\u8fd9\u4e9b\u6570\u636e，\u90a3\u4e48\u5b83\u8bfb\u53d6\u5230\u7684\u5c31\u662f\u4e00\u4efd\u6c38\u8fdc\u4e0d\u4f1a\u6b63\u5f0f\u751f\u6548\u7684\u6570\u636e\u3002<\/p>\n

        \u4e0b\u9762\u901a\u8fc7\u4e24\u4e2a\u5e76\u53d1\u4e8b\u52a1\u8fdb\u884c\u6f14\u793a：<\/p>\n

        \u5047\u8bbe\u8d26\u6237 A \u7684\u521d\u59cb\u4f59\u989d\u4e3a 1000 \u5143<\/p>\n

        \u4e8b\u52a1 T1：<\/p>\n

        START TRANSACTION;<\/p>\n

        UPDATE account
        \nSET balance = 500
        \nWHERE id = 1;<\/p>\n

        — \u6682\u65f6\u4e0d\u63d0\u4ea4\u4e8b\u52a1 <\/p>\n

        \u4e8b\u52a1 T2：<\/p>\n

        –\u4e3a\u4e86\u6f14\u793a\u810f\u8bfb，\u6211\u4eec\u9700\u8981\u5c06\u9694\u79bb\u7ea7\u522b\u8bbe\u7f6e\u4e3a\u8bfb\u672a\u63d0\u4ea4
        \nSET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;<\/p>\n

        START TRANSACTION;<\/p>\n

        SELECT balance
        \nFROM account
        \nWHERE id = 1; <\/p>\n

        \u6b64\u65f6，\u4f1a\u8bdd\u4e8c\u53ef\u80fd\u67e5\u8be2\u5230：<\/p>\n\n\nbalance<\/tr>\n\n
        500.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        \u4f46\u662f，\u8d26\u6237 A \u7684\u4f59\u989d\u4fee\u6539\u5c1a\u672a\u63d0\u4ea4\u3002<\/p>\n

        \u63a5\u4e0b\u6765，\u4f1a\u8bdd\u4e00\u6267\u884c：<\/p>\n

        ROLLBACK; <\/p>\n

        \u7531\u4e8e\u4e8b\u52a1 T1 \u56de\u6eda\u4e86，\u8d26\u6237 A \u7684\u4f59\u989d\u53c8\u6062\u590d\u4e3a 1000 \u5143\u3002<\/p>\n

        \u8fd9\u610f\u5473\u7740，\u4f1a\u8bdd\u4e8c\u4e4b\u524d\u8bfb\u53d6\u5230\u7684 500 \u5143，\u5b9e\u9645\u4e0a\u5e76\u6ca1\u6709\u6210\u4e3a\u6700\u7ec8\u751f\u6548\u7684\u6570\u636e\u3002\u8fd9\u5c31\u662f\u810f\u8bfb\u3002<\/p>\n

        3.2 \u4e0d\u53ef\u91cd\u590d\u8bfb<\/h3>\n

        \u4e0d\u53ef\u91cd\u590d\u8bfb\u662f\u6307\u540c\u4e00\u4e2a\u4e8b\u52a1<\/span>\u5728\u524d\u540e\u4e24\u6b21\u8bfb\u53d6\u540c\u4e00\u6761\u8bb0\u5f55<\/span>\u65f6，\u5f97\u5230\u4e86\u4e0d\u540c<\/span>\u7684\u7ed3\u679c<\/span>\u3002<\/p>\n

        \u9700\u8981\u6ce8\u610f\u7684\u662f，\u8fd9\u91cc\u5f3a\u8c03\u7684\u662f\u540c\u4e00\u4e2a\u4e8b\u52a1\u5bf9\u540c\u4e00\u6761\u8bb0\u5f55\u8fdb\u884c\u591a\u6b21\u8bfb\u53d6<\/span>\u3002<\/p>\n

        \u4e0e\u810f\u8bfb\u4e0d\u540c，\u4e0d\u53ef\u91cd\u590d\u8bfb\u662f\u56e0\u4e3a\u53e6\u4e00\u4e2a\u4e8b\u52a1\u4fee\u6539\u4e86\u76f8\u5173\u6570\u636e，\u5e76\u4e14\u63d0\u4ea4\u4e86\u4fee\u6539\u7ed3\u679c\u3002<\/p>\n

        \u5047\u8bbe\u8d26\u6237 A \u7684\u521d\u59cb\u4f59\u989d\u4e3a 1000 \u5143\u3002<\/p>\n

        \u4e3a\u4e86\u65b9\u4fbf\u89c2\u5bdf，\u6211\u4eec\u5c06\u4f1a\u8bdd\u4e00\u8bbe\u7f6e\u4e3a\u8bfb\u5df2\u63d0\u4ea4\u9694\u79bb\u7ea7\u522b\u3002<\/p>\n

        \u4e8b\u52a1 T1：<\/p>\n

        SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;<\/p>\n

        START TRANSACTION;<\/p>\n

        SELECT balance
        \nFROM account
        \nWHERE id = 1; <\/p>\n

        \u7b2c\u4e00\u6b21\u67e5\u8be2\u7ed3\u679c\u4e3a：<\/p>\n\n\nbalance<\/tr>\n\n
        1000.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        \u6b64\u65f6，\u4e8b\u52a1 T1 \u6682\u65f6\u4e0d\u63d0\u4ea4\u3002<\/p>\n

        \u4e8b\u52a1 T2：<\/p>\n

        UPDATE account
        \nSET balance = 800
        \nWHERE id = 1; <\/p>\n

        \u5728\u9ed8\u8ba4\u81ea\u52a8\u63d0\u4ea4\u5f00\u542f\u7684\u60c5\u51b5\u4e0b，\u8fd9\u6761\u8bed\u53e5\u6210\u529f\u6267\u884c\u540e，\u5176\u4fee\u6539\u4f1a\u81ea\u52a8\u63d0\u4ea4\u3002<\/p>\n

        \u6b64\u65f6，\u6570\u636e\u5e93\u4e2d\u7684\u8d26\u6237\u4f59\u989d\u5df2\u7ecf\u53d8\u4e3a 800 \u5143\u3002<\/p>\n

        \u63a5\u4e0b\u6765，\u4f1a\u8bdd\u4e00\u518d\u6b21\u6267\u884c\u76f8\u540c\u7684\u67e5\u8be2：<\/p>\n

        SELECT balance
        \nFROM account
        \nWHERE id = 1; <\/p>\n

        \u7b2c\u4e8c\u6b21\u67e5\u8be2\u7ed3\u679c\u4e3a：<\/p>\n\n\nbalance<\/tr>\n\n
        800.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        \u53ef\u4ee5\u770b\u5230，\u4e8b\u52a1 T1 \u5728\u81ea\u8eab\u4e8b\u52a1\u5c1a\u672a\u7ed3\u675f\u7684\u60c5\u51b5\u4e0b，\u524d\u540e\u4e24\u6b21\u8bfb\u53d6\u540c\u4e00\u6761\u8bb0\u5f55，\u5f97\u5230\u4e86\u4e0d\u540c\u7684\u7ed3\u679c\u3002\u8fd9\u5c31\u662f\u4e0d\u53ef\u91cd\u590d\u8bfb\u3002<\/p>\n

        \u6700\u540e，\u4f1a\u8bdd\u4e00\u6267\u884c：<\/p>\n

        COMMIT; <\/p>\n

        \u7ed3\u675f\u4e8b\u52a1\u3002<\/p>\n

        \u4e3a\u4ec0\u4e48\u4f1a\u51fa\u73b0\u4e0d\u53ef\u91cd\u590d\u8bfb？<\/p>\n

        \u8fd9\u4e0e MySQL \u7684\u9694\u79bb\u7ea7\u522b\u662f\u5f3a\u76f8\u5173\u7684，\u5728\u8bfb\u5df2\u63d0\u4ea4\u7684\u9694\u79bb\u7ea7\u522b\u4e0b，\u5e76\u53d1\u4e2d\u7684\u4e8b\u52a1\u53ef\u4ee5\u8bfb\u53d6\u5230\u5176\u4ed6\u4e8b\u52a1\u63d0\u4ea4\u7684\u6570\u636e\u3002<\/p>\n

        3.3 \u5e7b\u8bfb<\/h3>\n

        \u5e7b\u8bfb\u662f\u6307\u540c\u4e00\u4e2a\u4e8b\u52a1\u6309\u7167\u76f8\u540c\u7684\u67e5\u8be2\u6761\u4ef6，\u591a\u6b21\u67e5\u8be2\u7b26\u5408\u6761\u4ef6\u7684\u8bb0\u5f55\u65f6，\u7ed3\u679c\u96c6\u4e2d\u7684\u8bb0\u5f55\u6570\u91cf\u6216\u8bb0\u5f55\u96c6\u5408\u53d1\u751f\u4e86\u53d8\u5316\u3002<\/p>\n

        \u4e0e\u4e0d\u53ef\u91cd\u590d\u8bfb\u76f8\u6bd4，\u5e7b\u8bfb\u66f4\u5f3a\u8c03\u67e5\u8be2\u6761\u4ef6\u5bf9\u5e94\u7684\u7ed3\u679c\u96c6\u53d1\u751f\u4e86\u53d8\u5316\u3002<\/p>\n

        \u4f8b\u5982，\u6211\u4eec\u6267\u884c\u4ee5\u4e0b\u67e5\u8be2：<\/p>\n

        SELECT *
        \nFROM account
        \nWHERE balance >= 600; <\/p>\n

        \u7b2c\u4e00\u6b21\u67e5\u8be2\u65f6，\u6570\u636e\u5e93\u4e2d\u6709\u4e24\u6761\u8bb0\u5f55\u6ee1\u8db3\u6761\u4ef6\u3002\u5982\u679c\u5728\u4e24\u6b21\u67e5\u8be2\u4e4b\u95f4，\u53e6\u4e00\u4e2a\u4e8b\u52a1\u63d2\u5165\u4e86\u4e00\u6761\u4f59\u989d\u4e3a 700 \u5143\u7684\u65b0\u8d26\u6237\u8bb0\u5f55\u5e76\u63d0\u4ea4，\u90a3\u4e48\u518d\u6b21\u6267\u884c\u76f8\u540c\u7684\u67e5\u8be2\u65f6，\u5c31\u53ef\u80fd\u591a\u51fa\u4e00\u6761\u8bb0\u5f55\u3002\u8fd9\u5c31\u662f\u5178\u578b\u7684\u5e7b\u8bfb\u573a\u666f\u3002<\/p>\n\n\n\u5bf9\u6bd4\u7ef4\u5ea6\u4e0d\u53ef\u91cd\u590d\u8bfb\u5e7b\u8bfb<\/tr>\n\n\n\n
        \u5173\u6ce8\u91cd\u70b9<\/td>\n\u540c\u4e00\u6761\u8bb0\u5f55\u7684\u5185\u5bb9\u53d1\u751f\u53d8\u5316<\/td>\n\u6ee1\u8db3\u6761\u4ef6\u7684\u8bb0\u5f55\u96c6\u5408\u53d1\u751f\u53d8\u5316<\/td>\n<\/tr>\n
        \u5178\u578b\u539f\u56e0<\/td>\n\u5176\u4ed6\u4e8b\u52a1\u4fee\u6539\u5e76\u63d0\u4ea4\u5df2\u6709\u8bb0\u5f55<\/td>\n\u5176\u4ed6\u4e8b\u52a1\u63d2\u5165\u65b0\u8bb0\u5f55，\u6216\u4fee\u6539\u8bb0\u5f55\u4f7f\u5176\u6ee1\u8db3\u67e5\u8be2\u6761\u4ef6<\/td>\n<\/tr>\n
        \u5178\u578b\u8868\u73b0<\/td>\n\u540c\u4e00\u8d26\u6237\u4f59\u989d\u524d\u540e\u4e0d\u540c<\/td>\n\u76f8\u540c\u67e5\u8be2\u6761\u4ef6\u8fd4\u56de\u7684\u8bb0\u5f55\u96c6\u5408\u4e0d\u540c<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        \u4f8b\u5982：<\/p>\n

          \n
        • \n

          \u7b2c\u4e00\u6b21\u67e5\u8be2\u8d26\u6237 A \u7684\u4f59\u989d\u4e3a 1000 \u5143，\u7b2c\u4e8c\u6b21\u53d8\u6210 800 \u5143，\u5c5e\u4e8e\u4e0d\u53ef\u91cd\u590d\u8bfb\u3002<\/p>\n<\/li>\n

        • \n

          \u7b2c\u4e00\u6b21\u67e5\u8be2\u4f59\u989d\u5927\u4e8e\u7b49\u4e8e 600 \u5143\u7684\u8d26\u6237\u6709\u4e24\u6761，\u7b2c\u4e8c\u6b21\u53d8\u6210\u4e09\u6761，\u5c5e\u4e8e\u5178\u578b\u7684\u5e7b\u8bfb\u3002<\/p>\n<\/li>\n<\/ul>\n

          \u8fd9\u91cc\u9700\u8981\u5f3a\u8c03 MySQL InnoDB \u7684\u5b9e\u73b0\u7ec6\u8282：\u5728\u53ef\u91cd\u590d\u8bfb\u9694\u79bb\u7ea7\u522b\u4e0b，\u666e\u901a\u7684\u5feb\u7167\u8bfb\u4f1a\u57fa\u4e8e\u4e8b\u52a1\u7684 Read View \u8bfb\u53d6\u4e00\u81f4\u7684\u6570\u636e\u7248\u672c，\u56e0\u6b64\u540c\u4e00\u4e2a\u4e8b\u52a1\u91cd\u590d\u6267\u884c\u67e5\u8be2\u65f6，\u662f\u4e0d\u5b58\u5728\u5e7b\u8bfb\u7684\u60c5\u51b5\u7684\u3002<\/p>\n

          3.4\u00a0\u4e22\u5931\u66f4\u65b0<\/h3>\n

          \u4e22\u5931\u66f4\u65b0\u662f\u6307\u591a\u4e2a\u4e8b\u52a1\u5e76\u53d1\u4fee\u6539\u540c\u4e00\u4efd\u6570\u636e\u65f6，\u4e00\u4e2a\u4e8b\u52a1\u7684\u4fee\u6539\u7ed3\u679c\u88ab\u53e6\u4e00\u4e2a\u4e8b\u52a1\u8986\u76d6，\u5bfc\u81f4\u4e4b\u524d\u7684\u66f4\u65b0\u6ca1\u6709\u4f53\u73b0\u5728\u6700\u7ec8\u7ed3\u679c\u4e2d\u3002<\/p>\n

          \u5047\u8bbe\u8d26\u6237 A \u7684\u4f59\u989d\u4e3a 1000 \u5143\u3002<\/p>\n

          \u73b0\u5728\u6709\u4e24\u4e2a\u4e8b\u52a1：<\/p>\n

            \n
          • \n

            \u4e8b\u52a1 T1：\u4ece\u8d26\u6237 A \u4e2d\u6263\u9664 100 \u5143\u3002<\/p>\n<\/li>\n

          • \n

            \u4e8b\u52a1 T2：\u4ece\u8d26\u6237 A \u4e2d\u6263\u9664 200 \u5143\u3002<\/p>\n<\/li>\n<\/ul>\n

            \u5982\u679c\u4e24\u4e2a\u4e8b\u52a1\u90fd\u5148\u8bfb\u53d6\u4f59\u989d，\u518d\u7531\u5e94\u7528\u7a0b\u5e8f\u6839\u636e\u8bfb\u53d6\u7ed3\u679c\u8ba1\u7b97\u65b0\u7684\u4f59\u989d，\u53ef\u80fd\u51fa\u73b0\u4ee5\u4e0b\u60c5\u51b5\u3002<\/p>\n

            \u4f1a\u8bdd\u4e00\u6267\u884c：<\/p>\n

            START TRANSACTION;<\/p>\n

            SELECT balance
            \nFROM account
            \nWHERE id = 1; <\/p>\n

            \u67e5\u8be2\u7ed3\u679c\u4e3a 1000 \u5143\u3002<\/p>\n

            \u4e0e\u6b64\u540c\u65f6，\u4f1a\u8bdd\u4e8c\u4e5f\u8bfb\u53d6\u540c\u4e00\u6761\u8bb0\u5f55：<\/p>\n

            START TRANSACTION;<\/p>\n

            SELECT balance
            \nFROM account
            \nWHERE id = 1; <\/p>\n

            \u67e5\u8be2\u7ed3\u679c\u540c\u6837\u4e3a 1000 \u5143\u3002<\/p>\n

            \u6b64\u65f6，\u4e24\u4e2a\u4e8b\u52a1\u90fd\u57fa\u4e8e\u65e7\u4f59\u989d\u8fdb\u884c\u8ba1\u7b97\u3002<\/p>\n

            \u4e8b\u52a1 T1 \u8ba1\u7b97：1000 – 100 = 900<\/p>\n

            \u4e8b\u52a1 T2 \u8ba1\u7b97：1000 – 200 = 800<\/p>\n

            \u4f1a\u8bdd\u4e00\u6267\u884c：<\/p>\n

            UPDATE account
            \nSET balance = 900
            \nWHERE id = 1;<\/p>\n

            COMMIT; <\/p>\n

            \u6b64\u65f6，\u8d26\u6237\u4f59\u989d\u53d8\u4e3a 900 \u5143\u3002<\/p>\n

            \u4f1a\u8bdd\u4e8c\u6267\u884c：<\/p>\n

            UPDATE account
            \nSET balance = 800
            \nWHERE id = 1;<\/p>\n

            COMMIT; <\/p>\n

            \u5982\u679c\u8be5\u66f4\u65b0\u5728\u7b49\u5f85\u4f1a\u8bdd\u4e00\u91ca\u653e\u884c\u9501\u540e\u6210\u529f\u6267\u884c，\u90a3\u4e48\u8d26\u6237\u4f59\u989d\u6700\u7ec8\u53d8\u4e3a 800 \u5143\u3002<\/p>\n

            \u4f46\u662f，\u6b63\u786e\u7684\u7ed3\u679c\u5e94\u8be5\u662f：1000 – 100 – 200 = 700<\/p>\n

            \u6700\u7ec8\u7ed3\u679c\u5374\u662f 800 \u5143，\u8bf4\u660e T1 \u7684\u6263\u6b3e\u7ed3\u679c\u88ab T2 \u6839\u636e\u65e7\u6570\u636e\u8ba1\u7b97\u51fa\u7684\u7edd\u5bf9\u503c\u8986\u76d6\u4e86\u3002\u8fd9\u5c31\u662f\u4e22\u5931\u66f4\u65b0\u3002\u9700\u8981\u6ce8\u610f，\u4e0a\u8ff0\u8fc7\u7a0b\u5047\u8bbe\u4e24\u4e2a\u4e8b\u52a1\u901a\u8fc7\u5e94\u7528\u7a0b\u5e8f\u8bfb\u53d6\u65e7\u503c\u3001\u8ba1\u7b97\u7edd\u5bf9\u503c\u5e76\u5199\u56de\u3002\u5b9e\u9645\u7684 SQL \u6267\u884c\u4f1a\u53d7\u5230 InnoDB \u884c\u9501\u3001\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u4ee5\u53ca\u8bed\u53e5\u6267\u884c\u987a\u5e8f\u7b49\u56e0\u7d20\u5f71\u54cd\u3002<\/p>\n

            \u5bf9\u4e8e\u4e0a\u8ff0\u573a\u666f，\u6211\u4eec\u53ef\u4ee5\u76f4\u63a5\u5728 SQL \u4e2d\u5b8c\u6210\u4f59\u989d\u7684\u589e\u51cf，\u800c\u4e0d\u662f\u5148\u67e5\u8be2\u4f59\u989d，\u518d\u7531\u5e94\u7528\u7a0b\u5e8f\u8ba1\u7b97\u5e76\u5199\u5165\u4e00\u4e2a\u56fa\u5b9a\u7684\u65b0\u503c\u3002<\/p>\n

            \u4f8b\u5982，\u6263\u6b3e\u64cd\u4f5c\u53ef\u4ee5\u5199\u6210：<\/p>\n

            UPDATE account
            \nSET balance = balance – 100
            \nWHERE id = 1
            \n AND balance >= 100; <\/p>\n

            \u53e6\u4e00\u4e2a\u4e8b\u52a1\u6263\u6b3e 200 \u5143\u65f6，\u53ef\u4ee5\u6267\u884c：<\/p>\n

            UPDATE account
            \nSET balance = balance – 200
            \nWHERE id = 1
            \n AND balance >= 200; <\/p>\n

            \u5bf9\u4e8e\u540c\u4e00\u6761\u8bb0\u5f55，InnoDB \u4f1a\u901a\u8fc7\u884c\u9501\u534f\u8c03\u5e76\u53d1\u66f4\u65b0\u3002\u6bcf\u6761\u66f4\u65b0\u8bed\u53e5\u90fd\u4f1a\u57fa\u4e8e\u5176\u5b9e\u9645\u6267\u884c\u65f6\u80fd\u591f\u66f4\u65b0\u7684\u5f53\u524d\u8bb0\u5f55\u503c\u8fdb\u884c\u8ba1\u7b97，\u800c\u4e0d\u662f\u7b80\u5355\u5730\u5199\u5165\u5e94\u7528\u7a0b\u5e8f\u6b64\u524d\u8ba1\u7b97\u51fa\u7684\u65e7\u503c\u3002\u5728\u524d\u9762\u7684\u793a\u4f8b\u4e2d，\u5982\u679c\u4e24\u6b21\u6263\u6b3e\u90fd\u6210\u529f，\u90a3\u4e48\u6700\u7ec8\u4f59\u989d\u5c31\u5e94\u8be5\u662f 700 \u5143\u3002\u5b9e\u9645\u4e1a\u52a1\u4e2d，\u8fd8\u9700\u8981\u68c0\u67e5\u6bcf\u6761\u8bed\u53e5\u7684\u53d7\u5f71\u54cd\u884c\u6570，\u5e76\u5c06\u76f8\u5173\u4e1a\u52a1\u64cd\u4f5c\u653e\u5165\u4e8b\u52a1\u4e2d\u3002\u5982\u679c\u6263\u6b3e\u5931\u8d25\u6216\u5176\u4ed6\u64cd\u4f5c\u51fa\u73b0\u5f02\u5e38，\u5c31\u5e94\u8be5\u6839\u636e\u4e1a\u52a1\u8981\u6c42\u56de\u6eda\u6574\u4e2a\u4e8b\u52a1\u3002<\/p>\n

            \u5904\u7406\u4e22\u5931\u66f4\u65b0\u7684\u91cd\u70b9\u662f：\u907f\u514d\u57fa\u4e8e\u8fc7\u671f\u6570\u636e\u76f4\u63a5\u8986\u76d6\u6700\u65b0\u7ed3\u679c，\u5e76\u901a\u8fc7\u5408\u7406\u7684 SQL \u66f4\u65b0\u65b9\u5f0f\u4e0e\u5e76\u53d1\u63a7\u5236\u673a\u5236\u4fdd\u62a4\u6570\u636e<\/span>\u3002<\/p>\n

            \u56db\u3001\u4e8b\u52a1\u7684\u9694\u79bb\u7ea7\u522b<\/h2>\n

            \u5728\u4e0a\u4e00\u7ae0\u7684\u8bb2\u8ff0\u4e2d，\u5927\u5bb6\u4eec\u53ef\u80fd\u4f1a\u5b58\u5728\u8bb8\u591a\u7591\u60d1，\u7a76\u7adf\u662f\u5728\u4ec0\u4e48\u573a\u666f\u4e0b\u624d\u4f1a\u4ea7\u751f\u95ee\u9898，\u800c\u53c8\u662f\u5982\u4f55\u89e3\u51b3\u4e0a\u8ff0\u95ee\u9898\u7684\u5462？\u65e2\u7136\u591a\u4e2a\u4e8b\u52a1\u540c\u65f6\u6267\u884c\u53ef\u80fd\u76f8\u4e92\u5e72\u6270\u4ea7\u751f\u95ee\u9898，\u90a3\u4e48 MySQL \u5e94\u8be5\u5982\u4f55\u63a7\u5236\u5b83\u4eec\u4e4b\u95f4\u7684\u76f8\u4e92\u5f71\u54cd？<\/p>\n

            \u672c\u7ae0\u8282\u5c06\u4e3a\u4f60\u89e3\u7b54：MySQL \u7684\u4e8b\u52a1\u9694\u79bb\u673a\u5236\u3002<\/p>\n

            4.1 MySQL \u7684\u56db\u79cd\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/h3>\n

            MySQL \u652f\u6301\u7684\u56db\u79cd\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b：<\/p>\n

          • \u8bfb\u672a\u63d0\u4ea4（READ UNCOMMITTED）：\u9694\u79bb\u7a0b\u5ea6\u6700\u4f4e，\u5141\u8bb8\u8bfb\u53d6\u5176\u4ed6\u4e8b\u52a1\u5c1a\u672a\u63d0\u4ea4\u7684\u6570\u636e，\u56e0\u6b64\u4f1a\u51fa\u73b0\u810f\u8bfb\u3001\u4e0d\u53ef\u91cd\u590d\u8bfb\u3001\u5e7b\u8bfb\u3002<\/li>\n
          • \u8bfb\u5df2\u63d0\u4ea4（READ COMMITTED）：\u53ea\u80fd\u8bfb\u53d6\u5df2\u7ecf\u63d0\u4ea4\u7684\u6570\u636e，\u89e3\u51b3\u4e86\u810f\u8bfb\u7684\u95ee\u9898，\u4f46\u540c\u4e00\u4e2a\u4e8b\u52a1\u7684\u591a\u6b21\u67e5\u8be2\u53ef\u80fd\u8bfb\u5230\u4e0d\u540c\u7248\u672c\u7684\u6570\u636e，\u51fa\u73b0\u4e0d\u53ef\u91cd\u590d\u8bfb\u7684\u95ee\u9898\u3002<\/li>\n
          • \u53ef\u91cd\u590d\u8bfb（REPEATABLE READ）：MySQL InnoDB \u7684\u9ed8\u8ba4\u9694\u79bb\u7ea7\u522b，\u89e3\u51b3\u4e86\u4e0d\u53ef\u91cd\u590d\u8bfb\u7684\u95ee\u9898，\u5373\u7b2c\u4e00\u6b21\u8bfb\u53d6\u5c31\u662f\u6700\u7ec8\u7248\u672c（\u5f53\u524d\u4e8b\u52a1\u4e0d\u8fdb\u884c\u4fee\u6539\u6570\u636e），\u4fdd\u8bc1\u91cd\u590d\u8bfb\u53d6\u7684\u4e00\u81f4\u6027，\u4f46 InnoDB \u5b83\u4e5f\u4e00\u5e76\u89e3\u51b3\u4e86\u5e7b\u8bfb\u7684\u95ee\u9898，\u800c\u5176\u4ed6\u6570\u636e\u5e93\u4e0d\u4e00\u5b9a\u89e3\u51b3\u3002<\/li>\n
          • \u4e32\u884c\u5316（SERIALIZABLE）：\u9694\u79bb\u7a0b\u5ea6\u6700\u9ad8，\u901a\u8fc7\u6700\u4e25\u683c\u7684\u5e76\u53d1\u63a7\u5236，\u4f7f\u4e8b\u52a1\u7684\u6267\u884c\u7f16\u5199\u7b26\u5408\u4e32\u884c\u6267\u884c\u7684\u8981\u6c42，\u597d\u5904\u662f\u66f4\u5b89\u5168，\u4ee3\u4ef7\u662f\u964d\u4f4e\u5e76\u53d1\u80fd\u529b，\u964d\u4f4e\u6548\u7387\u3002<\/li>\n\n\n\n

            \u9694\u79bb\u7ea7\u522b<\/p>\n

            \u810f\u8bfb<\/p>\n

            \u4e0d\u53ef\u91cd\u590d\u8bfb<\/p>\n

            \u5e7b\u8bfb<\/p>\n<\/tr>\n

            \n\n\n\n
            \n

            \u8bfb\u672a\u63d0\u4ea4 RU<\/p>\n<\/td>\n

            		\n

            \u53ef\u80fd<\/p>\n<\/td>\n

            		\n

            \u53ef\u80fd<\/p>\n<\/td>\n

            		\n

            \u53ef\u80fd<\/p>\n<\/td>\n<\/tr>\n

            \n

            \u8bfb\u5df2\u63d0\u4ea4 RC<\/p>\n<\/td>\n

            		\n

            \u4e0d\u4f1a<\/p>\n<\/td>\n

            		\n

            \u53ef\u80fd<\/p>\n<\/td>\n

            		\n

            \u53ef\u80fd<\/p>\n<\/td>\n<\/tr>\n

            \n

            \u53ef\u91cd\u590d\u8bfb RR<\/p>\n<\/td>\n

            		\n

            \u4e0d\u4f1a<\/p>\n<\/td>\n

            		\n

            \u4e0d\u4f1a<\/p>\n<\/td>\n

            		\n

            InnoDB \u6709\u4e13\u95e8\u5904\u7406\u673a\u5236<\/p>\n<\/td>\n<\/tr>\n

            \n

            \u4e32\u884c\u5316 Serializable<\/p>\n<\/td>\n

            		\n

            \u4e0d\u4f1a<\/p>\n<\/td>\n

            		\n

            \u4e0d\u4f1a<\/p>\n<\/td>\n

            		\n

            \u4e0d\u4f1a<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

            4.2 \u8bfb\u672a\u63d0\u4ea4（READ UNCOMMITTED）<\/h3>\n

            \u8bfb\u672a\u63d0\u4ea4\u662f\u56db\u79cd\u9694\u79bb\u7ea7\u522b\u4e2d\u9650\u5236\u6700\u5c11\u7684\u4e00\u79cd\u3002<\/p>\n

            \u5728\u8fd9\u79cd\u9694\u79bb\u7ea7\u522b\u4e0b，\u4e00\u4e2a\u4e8b\u52a1\u53ef\u4ee5\u8bfb\u53d6\u53e6\u4e00\u4e2a\u4e8b\u52a1\u5c1a\u672a\u63d0\u4ea4\u7684\u4fee\u6539，\u56e0\u6b64\u53ef\u80fd\u4ea7\u751f\u810f\u8bfb\u3002<\/p>\n

            \u4e3a\u4e86\u9a8c\u8bc1\u8fd9\u4e00\u70b9，\u6211\u4eec\u4f7f\u7528\u4e24\u4e2a\u6570\u636e\u5e93\u4f1a\u8bdd\u8fdb\u884c\u5b9e\u9a8c\u3002<\/p>\n

            \u5b9e\u9a8c\u524d\u63d0：\u4f7f\u7528\u4e0a\u4e00\u7ae0\u521b\u5efa\u7684 accout \u8868，\u786e\u4fdd\u8d26\u6237 A \u7684 id = 1，\u521d\u59cb\u4f59\u989d\u4e3a 1000 \u5143\u3002<\/p>\n

            \u9996\u5148，\u5728\u4f1a\u8bdd\u4e00\u4e2d\u5f00\u542f\u4e8b\u52a1\u5e76\u4fee\u6539\u4f59\u989d：<\/p>\n

            SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;<\/p>\n

            START TRANSACTION;<\/p>\n

            UPDATE account
            \nSET balance = 500
            \nWHERE id = 1; <\/p>\n

            \u6ce8\u610f，\u6b64\u65f6\u4e0d\u8981\u63d0\u4ea4\u4e8b\u52a1\u3002<\/p>\n

            \u63a5\u7740，\u5728\u4f1a\u8bdd\u4e8c\u4e2d\u6267\u884c：<\/p>\n

            SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;<\/p>\n

            START TRANSACTION;<\/p>\n

            SELECT balance
            \nFROM account
            \nWHERE id = 1; <\/p>\n

            \u6b64\u65f6，\u4f1a\u8bdd\u4e8c\u53ef\u80fd\u67e5\u8be2\u5230\u4ee5\u4e0b\u7ed3\u679c：<\/p>\n\n\nbalance<\/tr>\n\n
            500.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

            \u4f46\u662f，\u4f1a\u8bdd\u4e00\u5bf9\u4f59\u989d\u7684\u4fee\u6539\u8fd8\u6ca1\u6709\u63d0\u4ea4\u3002<\/p>\n

            \u63a5\u4e0b\u6765，\u56de\u5230\u4f1a\u8bdd\u4e00\u6267\u884c：<\/p>\n

            ROLLBACK; <\/p>\n

            \u4f1a\u8bdd\u4e00\u7684\u4fee\u6539\u88ab\u64a4\u9500，\u8d26\u6237\u4f59\u989d\u6062\u590d\u4e3a 1000 \u5143\u3002<\/p>\n

            \u8fd9\u610f\u5473\u7740，\u4f1a\u8bdd\u4e8c\u4e4b\u524d\u8bfb\u53d6\u5230\u7684 500 \u5143，\u5e76\u4e0d\u662f\u4e00\u4e2a\u5df2\u7ecf\u63d0\u4ea4\u7684\u4fee\u6539\u7ed3\u679c\u3002<\/p>\n

            \u8fd9\u5c31\u662f\u810f\u8bfb\u3002<\/p>\n

            \u5b9e\u9a8c\u7ed3\u675f\u540e，\u5728\u4f1a\u8bdd\u4e8c\u6267\u884c：<\/p>\n

            COMMIT; <\/p>\n

            \u901a\u8fc7\u5b9e\u9a8c\u53ef\u4ee5\u53d1\u73b0，\u8bfb\u672a\u63d0\u4ea4\u5141\u8bb8\u4e8b\u52a1\u8bfb\u53d6\u5176\u4ed6\u4e8b\u52a1\u5c1a\u672a\u63d0\u4ea4\u7684\u6570\u636e，\u56e0\u6b64\u53ef\u80fd\u53d1\u751f\u810f\u8bfb\u3002<\/p>\n

            \u8fd9\u79cd\u9694\u79bb\u7ea7\u522b\u7684\u5e76\u53d1\u9650\u5236\u8f83\u5f31，\u901a\u5e38\u4e0d\u9002\u5408\u5bf9\u6570\u636e\u6b63\u786e\u6027\u8981\u6c42\u8f83\u9ad8\u7684\u4e1a\u52a1\u573a\u666f\u3002<\/p>\n

            4.3 \u8bfb\u5df2\u63d0\u4ea4（READ COMMITTED）<\/h3>\n

            \u8bfb\u5df2\u63d0\u4ea4\u8981\u6c42\u4e8b\u52a1\u53ea\u80fd\u8bfb\u53d6\u5df2\u7ecf\u63d0\u4ea4\u7684\u6570\u636e\u3002<\/p>\n

            \u4e0e\u8bfb\u672a\u63d0\u4ea4\u76f8\u6bd4，\u5b83\u80fd\u591f\u907f\u514d\u810f\u8bfb\u3002\u4f46\u662f，\u5b83\u5e76\u4e0d\u80fd\u4fdd\u8bc1\u540c\u4e00\u4e2a\u4e8b\u52a1\u5728\u591a\u6b21\u67e5\u8be2\u65f6\u59cb\u7ec8\u8bfb\u53d6\u5230\u76f8\u540c\u7684\u6570\u636e\u3002<\/p>\n

            \u5728 InnoDB \u4e2d，\u8bfb\u5df2\u63d0\u4ea4\u7684\u666e\u901a\u4e00\u81f4\u6027\u8bfb\u901a\u5e38\u4f1a\u5728\u6bcf\u6b21\u67e5\u8be2\u65f6\u83b7\u53d6\u65b0\u7684 Read View\u3002\u56e0\u6b64，\u5f53\u5176\u4ed6\u4e8b\u52a1\u63d0\u4ea4\u4e86\u6570\u636e\u4fee\u6539\u540e，\u5f53\u524d\u4e8b\u52a1\u518d\u6b21\u67e5\u8be2\u65f6，\u5c31\u53ef\u80fd\u8bfb\u53d6\u5230\u65b0\u7684\u6570\u636e\u7248\u672c\u3002<\/p>\n

            \u5b9e\u9a8c\u524d\u63d0：\u786e\u4fdd\u8d26\u6237 A \u7684\u4f59\u989d\u4e3a 1000 \u5143，\u5e76\u4e14\u6ca1\u6709\u5176\u4ed6\u4e8b\u52a1\u6b63\u5728\u4fee\u6539\u8fd9\u6761\u8bb0\u5f55\u3002<\/p>\n

            \u9996\u5148，\u5728\u4f1a\u8bdd\u4e00\u4e2d\u5f00\u542f\u4e8b\u52a1：<\/p>\n

            SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;<\/p>\n

            START TRANSACTION;<\/p>\n

            SELECT balance
            \nFROM account
            \nWHERE id = 1; <\/p>\n

            \u7b2c\u4e00\u6b21\u67e5\u8be2\u7ed3\u679c\u4e3a：<\/p>\n\n\nbalance<\/tr>\n\n
            1000.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

            \u6b64\u65f6，\u4f1a\u8bdd\u4e00\u4e0d\u8981\u63d0\u4ea4\u4e8b\u52a1\u3002<\/p>\n

            \u63a5\u7740，\u5728\u4f1a\u8bdd\u4e8c\u4e2d\u4fee\u6539\u8d26\u6237\u4f59\u989d\u5e76\u63d0\u4ea4：<\/p>\n

            START TRANSACTION;<\/p>\n

            UPDATE account
            \nSET balance = 800
            \nWHERE id = 1;<\/p>\n

            COMMIT; <\/p>\n

            \u6b64\u65f6，\u8d26\u6237\u4f59\u989d\u5df2\u7ecf\u6210\u529f\u4fee\u6539\u4e3a 800 \u5143\u3002<\/p>\n

            \u56de\u5230\u4f1a\u8bdd\u4e00，\u518d\u6b21\u6267\u884c\u76f8\u540c\u7684\u67e5\u8be2：<\/p>\n

            SELECT balance
            \nFROM account
            \nWHERE id = 1; <\/p>\n

            \u7b2c\u4e8c\u6b21\u67e5\u8be2\u7ed3\u679c\u4e3a：<\/p>\n\n\nbalance<\/tr>\n\n
            800.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

            \u53ef\u4ee5\u53d1\u73b0，\u4f1a\u8bdd\u4e00\u5728\u540c\u4e00\u4e2a\u4e8b\u52a1\u4e2d，\u4e24\u6b21\u6267\u884c\u76f8\u540c\u7684\u67e5\u8be2，\u5374\u5f97\u5230\u4e86\u4e0d\u540c\u7684\u7ed3\u679c\u3002<\/p>\n

            \u8fd9\u5c31\u662f\u4e0d\u53ef\u91cd\u590d\u8bfb\u3002<\/p>\n

            \u5b9e\u9a8c\u7ed3\u675f\u540e，\u5728\u4f1a\u8bdd\u4e00\u6267\u884c：<\/p>\n

            COMMIT; <\/p>\n

            \u8bfb\u5df2\u63d0\u4ea4\u53ef\u4ee5\u907f\u514d\u810f\u8bfb，\u4f46\u4ecd\u7136\u53ef\u80fd\u51fa\u73b0\u4e0d\u53ef\u91cd\u590d\u8bfb\u3002<\/p>\n

            \u5176\u539f\u56e0\u5728\u4e8e，InnoDB \u5728 RC \u9694\u79bb\u7ea7\u522b\u4e0b，\u666e\u901a\u4e00\u81f4\u6027\u8bfb\u901a\u5e38\u4e3a\u6bcf\u6b21\u67e5\u8be2\u83b7\u53d6\u65b0\u7684 Read View\u3002\u5f53\u5176\u4ed6\u4e8b\u52a1\u63d0\u4ea4\u4fee\u6539\u540e，\u540e\u7eed\u67e5\u8be2\u5c31\u53ef\u80fd\u8bfb\u53d6\u5230\u65b0\u7684\u6570\u636e\u7248\u672c\u3002<\/p>\n

            \u6b64\u5916，RC \u4e5f\u53ef\u80fd\u51fa\u73b0\u5e7b\u8bfb\u3002\u4f8b\u5982，\u4e00\u4e2a\u4e8b\u52a1\u4e24\u6b21\u67e5\u8be2\u4f59\u989d\u5927\u4e8e\u7b49\u4e8e 600 \u5143\u7684\u8d26\u6237，\u5728\u4e24\u6b21\u67e5\u8be2\u4e4b\u95f4，\u53e6\u4e00\u4e2a\u4e8b\u52a1\u63d2\u5165\u4e86\u4e00\u6761\u6ee1\u8db3\u6761\u4ef6\u5e76\u63d0\u4ea4\u7684\u65b0\u8bb0\u5f55，\u90a3\u4e48\u7b2c\u4e8c\u6b21\u67e5\u8be2\u5c31\u53ef\u80fd\u591a\u51fa\u4e00\u6761\u8bb0\u5f55\u3002<\/p>\n

            4.4 \u53ef\u91cd\u590d\u8bfb（REPEATABLE READ）<\/h3>\n

            \u53ef\u91cd\u590d\u8bfb\u662f InnoDB \u9ed8\u8ba4\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u3002<\/p>\n

            \u5b83\u7684\u6838\u5fc3\u7279\u70b9\u662f：\u5728\u540c\u4e00\u4e2a\u4e8b\u52a1\u4e2d，\u666e\u901a\u4e00\u81f4\u6027\u8bfb\u901a\u5e38\u57fa\u4e8e\u540c\u4e00\u4e2a Read View \u8bfb\u53d6\u6570\u636e，\u4ece\u800c\u4fdd\u8bc1\u591a\u6b21\u8bfb\u53d6\u7684\u4e00\u81f4\u6027\u3002<\/p>\n

            \u4e5f\u5c31\u662f\u8bf4，\u5373\u4f7f\u5176\u4ed6\u4e8b\u52a1\u4fee\u6539\u5e76\u63d0\u4ea4\u4e86\u6570\u636e，\u5f53\u524d\u4e8b\u52a1\u91cd\u590d\u6267\u884c\u666e\u901a\u67e5\u8be2\u65f6，\u4ecd\u7136\u53ef\u4ee5\u8bfb\u53d6\u5230\u539f\u6765\u5feb\u7167\u4e2d\u7684\u6570\u636e\u7248\u672c\u3002<\/p>\n

            \u5b9e\u9a8c\u524d\u63d0：\u786e\u4fdd\u8d26\u6237 A \u7684\u4f59\u989d\u4e3a 1000 \u5143，\u5e76\u4e14\u6ca1\u6709\u5176\u4ed6\u4e8b\u52a1\u6b63\u5728\u4fee\u6539\u8fd9\u6761\u8bb0\u5f55\u3002<\/p>\n

            \u9996\u5148，\u5728\u4f1a\u8bdd\u4e00\u4e2d\u5f00\u542f\u4e8b\u52a1\u5e76\u67e5\u8be2\u4f59\u989d：<\/p>\n

            SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;<\/p>\n

            START TRANSACTION;<\/p>\n

            SELECT balance
            \nFROM account
            \nWHERE id = 1; <\/p>\n

            \u7b2c\u4e00\u6b21\u67e5\u8be2\u7ed3\u679c\u4e3a：<\/p>\n\n\nbalance<\/tr>\n\n
            1000.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

            \u8fd9\u6b21\u666e\u901a\u4e00\u81f4\u6027\u8bfb\u5efa\u7acb\u4e86\u5f53\u524d\u4e8b\u52a1\u4f7f\u7528\u7684 Read View\u3002<\/p>\n

            \u63a5\u7740，\u5728\u4f1a\u8bdd\u4e8c\u4e2d\u4fee\u6539\u4f59\u989d\u5e76\u63d0\u4ea4：<\/p>\n

            START TRANSACTION;<\/p>\n

            UPDATE account
            \nSET balance = 800
            \nWHERE id = 1;<\/p>\n

            COMMIT; <\/p>\n

            \u6b64\u65f6，\u8d26\u6237\u7684\u6700\u65b0\u4f59\u989d\u5df2\u7ecf\u53d8\u4e3a 800 \u5143\u3002<\/p>\n

            \u4f46\u662f，\u4f1a\u8bdd\u4e00\u5c1a\u672a\u7ed3\u675f\u4e8b\u52a1\u3002<\/p>\n

            \u56de\u5230\u4f1a\u8bdd\u4e00，\u518d\u6b21\u6267\u884c：<\/p>\n

            SELECT balance
            \nFROM account
            \nWHERE id = 1; <\/p>\n

            \u7b2c\u4e8c\u6b21\u67e5\u8be2\u7ed3\u679c\u901a\u5e38\u4ecd\u7136\u4e3a：<\/p>\n\n\nbalance<\/tr>\n\n
            1000.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

            \u4e3a\u4ec0\u4e48\u4e0d\u662f 800 \u5143？<\/p>\n

            \u56e0\u4e3a\u5728 RR \u9694\u79bb\u7ea7\u522b\u4e0b，\u4f1a\u8bdd\u4e00\u7684\u666e\u901a\u4e00\u81f4\u6027\u8bfb\u7ee7\u7eed\u4f7f\u7528\u539f\u6765\u7684 Read View\u3002\u867d\u7136\u4f1a\u8bdd\u4e8c\u5df2\u7ecf\u63d0\u4ea4\u4e86\u4fee\u6539，\u4f46\u65b0\u7248\u672c\u4e0d\u5c5e\u4e8e\u4f1a\u8bdd\u4e00\u5f53\u524d\u5feb\u7167\u53ef\u89c1\u7684\u6570\u636e，\u56e0\u6b64\u4f1a\u8bdd\u4e00\u4ecd\u7136\u8bfb\u53d6\u5230 1000 \u5143\u3002<\/p>\n

            \u5b9e\u9a8c\u7ed3\u675f\u540e，\u5728\u4f1a\u8bdd\u4e00\u6267\u884c：<\/p>\n

            COMMIT; <\/p>\n

            \u5982\u679c\u6b64\u65f6\u91cd\u65b0\u5f00\u542f\u4e00\u4e2a\u4e8b\u52a1\u5e76\u67e5\u8be2\u4f59\u989d，\u5c31\u53ef\u4ee5\u770b\u5230\u6700\u65b0\u63d0\u4ea4\u7684 800 \u5143\u3002<\/p>\n

            \u901a\u8fc7\u5b9e\u9a8c\u53ef\u4ee5\u53d1\u73b0，InnoDB \u7684 RR \u80fd\u591f\u907f\u514d\u666e\u901a\u4e00\u81f4\u6027\u8bfb\u4e2d\u7684\u810f\u8bfb\u548c\u4e0d\u53ef\u91cd\u590d\u8bfb\u3002<\/p>\n

            \u4e0d\u8fc7，\u8fd9\u5e76\u4e0d\u610f\u5473\u7740 InnoDB \u7684\u6240\u6709\u67e5\u8be2\u90fd\u53ea\u8bfb\u53d6\u5feb\u7167\u4e2d\u7684\u5386\u53f2\u7248\u672c\u3002<\/p>\n

            \u56e0\u6b64，\u7406\u89e3 RR \u65f6，\u9700\u8981\u533a\u5206\u5feb\u7167\u8bfb\u4e0e\u5f53\u524d\u8bfb\u3002MVCC \u548c\u9501\u673a\u5236\u4f1a\u5728\u540e\u7eed\u7ae0\u8282\u4e2d\u8be6\u7ec6\u4ecb\u7ecd\u3002<\/p>\n

            4.5 \u4e32\u884c\u5316（SERIALIZABLE）<\/h3>\n

            \u4e32\u884c\u5316\u662f\u56db\u79cd\u9694\u79bb\u7ea7\u522b\u4e2d\u9694\u79bb\u7a0b\u5ea6\u6700\u9ad8\u7684\u4e00\u79cd\u3002<\/p>\n

            \u5b83\u8981\u6c42\u5e76\u53d1\u4e8b\u52a1\u7684\u6267\u884c\u6548\u679c\u7b26\u5408\u4e32\u884c\u6267\u884c\u7684\u8981\u6c42，\u4ece\u800c\u907f\u514d\u810f\u8bfb\u3001\u4e0d\u53ef\u91cd\u590d\u8bfb\u548c\u5e7b\u8bfb\u7b49\u7ecf\u5178\u5e76\u53d1\u95ee\u9898\u3002<\/p>\n

            \u4e3a\u4e86\u5b9e\u73b0\u66f4\u4e25\u683c\u7684\u9694\u79bb，\u6570\u636e\u5e93\u53ef\u80fd\u9700\u8981\u8ba9\u4e8b\u52a1\u7b49\u5f85\u5176\u4ed6\u4e8b\u52a1\u91ca\u653e\u9501，\u56e0\u6b64\u4e32\u884c\u5316\u901a\u5e38\u4f1a\u5e26\u6765\u66f4\u9ad8\u7684\u5e76\u53d1\u63a7\u5236\u5f00\u9500\u3002<\/p>\n

            \u5b9e\u9a8c\u524d\u63d0：\u786e\u4fdd\u8d26\u6237 A \u7684\u4f59\u989d\u4e3a 1000 \u5143\u3002<\/p>\n

            \u9996\u5148，\u5728\u4f1a\u8bdd\u4e00\u4e2d\u8bbe\u7f6e\u4e32\u884c\u5316\u9694\u79bb\u7ea7\u522b，\u5e76\u5f00\u542f\u4e8b\u52a1：<\/p>\n

            SET SESSION TRANSACTION ISOLATION LEVEL SERIALIZABLE;<\/p>\n

            START TRANSACTION;<\/p>\n

            SELECT balance
            \nFROM account
            \nWHERE id = 1; <\/p>\n

            \u67e5\u8be2\u7ed3\u679c\u4e3a：<\/p>\n\n\nbalance<\/tr>\n\n
            1000.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

            \u6b64\u65f6，\u4e0d\u8981\u63d0\u4ea4\u4f1a\u8bdd\u4e00\u7684\u4e8b\u52a1\u3002<\/p>\n

            \u5728 InnoDB \u4e2d，\u5f53\u4f7f\u7528\u663e\u5f0f\u4e8b\u52a1\u4e14\u9694\u79bb\u7ea7\u522b\u4e3a SERIALIZABLE \u65f6，\u666e\u901a SELECT \u4f1a\u91c7\u7528\u5171\u4eab\u9501\u5b9a\u8bfb\u7684\u65b9\u5f0f\u3002<\/p>\n

            \u63a5\u4e0b\u6765，\u5728\u4f1a\u8bdd\u4e8c\u4e2d\u6267\u884c：<\/p>\n

            START TRANSACTION;<\/p>\n

            UPDATE account
            \nSET balance = 800
            \nWHERE id = 1; <\/p>\n

            \u6b64\u65f6，\u4f1a\u8bdd\u4e8c\u7684 UPDATE \u53ef\u80fd\u4e00\u76f4\u7b49\u5f85，\u65e0\u6cd5\u7acb\u5373\u5b8c\u6210\u3002<\/p>\n

            \u8fd9\u662f\u56e0\u4e3a\u4f1a\u8bdd\u4e00\u4ecd\u7136\u6301\u6709\u76f8\u5173\u8bb0\u5f55\u7684\u5171\u4eab\u9501，\u800c\u4f1a\u8bdd\u4e8c\u9700\u8981\u83b7\u53d6\u6392\u4ed6\u9501\u624d\u80fd\u4fee\u6539\u8fd9\u6761\u8bb0\u5f55\u3002<\/p>\n

            \u73b0\u5728，\u56de\u5230\u4f1a\u8bdd\u4e00\u6267\u884c：<\/p>\n

            COMMIT; <\/p>\n

            \u4f1a\u8bdd\u4e00\u63d0\u4ea4\u4e8b\u52a1\u5e76\u91ca\u653e\u76f8\u5173\u9501\u3002<\/p>\n

            \u6b64\u65f6，\u4f1a\u8bdd\u4e8c\u7b49\u5f85\u4e2d\u7684 UPDATE \u5c31\u53ef\u4ee5\u7ee7\u7eed\u6267\u884c\u3002\u5f85\u5176\u6210\u529f\u5b8c\u6210\u540e，\u518d\u5728\u4f1a\u8bdd\u4e8c\u6267\u884c：<\/p>\n

            COMMIT; <\/p>\n

            \u6700\u540e\u67e5\u8be2\u8d26\u6237\u4f59\u989d，\u53ef\u4ee5\u770b\u5230\u4fee\u6539\u540e\u7684\u7ed3\u679c\u4e3a 800 \u5143\u3002<\/p>\n

            \u901a\u8fc7\u5b9e\u9a8c\u53ef\u4ee5\u53d1\u73b0，\u5728\u4e32\u884c\u5316\u9694\u79bb\u7ea7\u522b\u4e0b，\u6570\u636e\u5e93\u4f1a\u91c7\u7528\u66f4\u4e25\u683c\u7684\u5e76\u53d1\u63a7\u5236\u65b9\u5f0f，\u5fc5\u8981\u65f6\u8ba9\u4e8b\u52a1\u7b49\u5f85，\u4ece\u800c\u9650\u5236\u5e76\u53d1\u4e8b\u52a1\u5bf9\u540c\u4e00\u6570\u636e\u7684\u8bbf\u95ee\u3002<\/p>\n

            \u4e32\u884c\u5316\u80fd\u591f\u63d0\u4f9b\u66f4\u5f3a\u7684\u9694\u79bb，\u4f46\u4e5f\u53ef\u80fd\u589e\u52a0\u9501\u7b49\u5f85\u548c\u6b7b\u9501\u7684\u98ce\u9669，\u964d\u4f4e\u7cfb\u7edf\u7684\u5e76\u53d1\u80fd\u529b\u3002<\/p>\n

            \u56e0\u6b64，\u5728\u5b9e\u9645\u9879\u76ee\u4e2d，\u9700\u8981\u6839\u636e\u4e1a\u52a1\u7684\u4e00\u81f4\u6027\u8981\u6c42\u548c\u5e76\u53d1\u538b\u529b\u9009\u62e9\u5408\u9002\u7684\u9694\u79bb\u7ea7\u522b\u3002<\/p>\n

            4.6 \u67e5\u770b\u4e0e\u8bbe\u7f6e\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/h3>\n

            MySQL \u5141\u8bb8\u6211\u4eec\u67e5\u770b\u548c\u8bbe\u7f6e\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u3002\u6839\u636e\u4f5c\u7528\u8303\u56f4\u7684\u4e0d\u540c，\u53ef\u4ee5\u5206\u4e3a\u5168\u5c40\u7ea7\u522b（GLOBAL）\u548c\u4f1a\u8bdd\u7ea7\u522b（SESSION）\u3002<\/p>\n

            4.6.1 \u67e5\u770b\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/h4>\n

            1. \u67e5\u770b\u5168\u5c40\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/p>\n

            SELECT @@GLOBAL.transaction_isolation; <\/p>\n

            \u8be5\u8bed\u53e5\u7528\u4e8e\u67e5\u770b MySQL \u670d\u52a1\u5668\u5f53\u524d\u7684\u5168\u5c40\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b，\u4e5f\u5c31\u662f\u65b0\u5efa\u4f1a\u8bdd\u9ed8\u8ba4\u4f7f\u7528\u7684\u9694\u79bb\u7ea7\u522b\u3002<\/p>\n

            2. \u67e5\u770b\u5f53\u524d\u4f1a\u8bdd\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/p>\n

            SELECT @@SESSION.transaction_isolation; <\/p>\n

            \u8be5\u8bed\u53e5\u7528\u4e8e\u67e5\u770b\u5f53\u524d\u6570\u636e\u5e93\u8fde\u63a5\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u3002<\/p>\n

            \u4e5f\u53ef\u4ee5\u7b80\u5199\u4e3a：<\/p>\n

            SELECT @@transaction_isolation; <\/p>\n

            4.6.2 \u8bbe\u7f6e\u4f1a\u8bdd\u7ea7\u522b\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/h4>\n

            \u5982\u679c\u53ea\u60f3\u4fee\u6539\u5f53\u524d\u6570\u636e\u5e93\u8fde\u63a5\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b，\u53ef\u4ee5\u4f7f\u7528 SET SESSION\u3002<\/p>\n

            \u4f8b\u5982，\u5c06\u5f53\u524d\u4f1a\u8bdd\u7684\u9694\u79bb\u7ea7\u522b\u8bbe\u7f6e\u4e3a\u8bfb\u5df2\u63d0\u4ea4：<\/p>\n

            SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED; <\/p>\n

            \u8bbe\u7f6e\u5b8c\u6210\u540e，\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u8bed\u53e5\u9a8c\u8bc1：<\/p>\n

            SELECT @@SESSION.transaction_isolation; <\/p>\n

            \u9700\u8981\u6ce8\u610f，\u4f1a\u8bdd\u7ea7\u522b\u7684\u8bbe\u7f6e\u53ea\u5bf9\u5f53\u524d\u6570\u636e\u5e93\u8fde\u63a5\u751f\u6548，\u4e0d\u4f1a\u5f71\u54cd\u5176\u4ed6\u8fde\u63a5，\u4e5f\u4e0d\u4f1a\u4fee\u6539\u670d\u52a1\u5668\u7684\u5168\u5c40\u9ed8\u8ba4\u503c\u3002<\/p>\n

            \u6b64\u5916，\u8be5\u8bbe\u7f6e\u4e0d\u4f1a\u6539\u53d8\u5df2\u7ecf\u5f00\u59cb\u6267\u884c\u7684\u4e8b\u52a1\u7684\u9694\u79bb\u7ea7\u522b，\u800c\u662f\u7528\u4e8e\u5f53\u524d\u4f1a\u8bdd\u540e\u7eed\u5f00\u542f\u7684\u4e8b\u52a1\u3002<\/p>\n

            4.6.3 \u8bbe\u7f6e\u5168\u5c40\u7ea7\u522b\u7684\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b<\/h4>\n

            \u5982\u679c\u5e0c\u671b\u4fee\u6539 MySQL \u670d\u52a1\u5668\u7684\u5168\u5c40\u9ed8\u8ba4\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b，\u53ef\u4ee5\u4f7f\u7528 SET GLOBAL\u3002<\/p>\n

            \u4f8b\u5982，\u5c06\u5168\u5c40\u9694\u79bb\u7ea7\u522b\u8bbe\u7f6e\u4e3a\u8bfb\u5df2\u63d0\u4ea4：<\/p>\n

            SET GLOBAL TRANSACTION ISOLATION LEVEL READ COMMITTED; <\/p>\n

            \u7136\u540e\u67e5\u770b\u5168\u5c40\u8bbe\u7f6e：<\/p>\n

            SELECT @@GLOBAL.transaction_isolation; <\/p>\n

            \u6b64\u65f6，\u5168\u5c40\u9ed8\u8ba4\u9694\u79bb\u7ea7\u522b\u5df2\u7ecf\u4fee\u6539\u4e3a READ-COMMITTED\u3002<\/p>\n

            \u9700\u8981\u6ce8\u610f\u4ee5\u4e0b\u51e0\u70b9：<\/p>\n

          • \n

            \u53ea\u5f71\u54cd\u65b0\u5efa\u4f1a\u8bdd\u3002 \u4fee\u6539\u5168\u5c40\u9694\u79bb\u7ea7\u522b\u540e，\u65b0\u5efa\u7acb\u7684\u6570\u636e\u5e93\u8fde\u63a5\u9ed8\u8ba4\u4f7f\u7528\u65b0\u7684\u9694\u79bb\u7ea7\u522b\u3002<\/p>\n<\/li>\n

          • \n

            \u4e0d\u5f71\u54cd\u5df2\u6709\u4f1a\u8bdd\u3002 \u5df2\u7ecf\u5efa\u7acb\u7684\u6570\u636e\u5e93\u8fde\u63a5\u4ecd\u7136\u4fdd\u7559\u5404\u81ea\u7684\u4f1a\u8bdd\u7ea7\u522b\u8bbe\u7f6e，\u4e0d\u4f1a\u56e0\u4e3a\u5168\u5c40\u8bbe\u7f6e\u6539\u53d8\u800c\u81ea\u52a8\u66f4\u65b0\u3002<\/p>\n<\/li>\n

          • \n

            \u9700\u8981\u76f8\u5e94\u6743\u9650\u3002 \u4fee\u6539\u5168\u5c40\u8bbe\u7f6e\u9700\u8981\u5177\u5907\u76f8\u5e94\u7684\u7ba1\u7406\u6743\u9650，\u5177\u4f53\u6743\u9650\u8981\u6c42\u53d6\u51b3\u4e8e MySQL \u7248\u672c\u548c\u914d\u7f6e\u3002<\/p>\n<\/li>\n

          • \n

            \u91cd\u542f\u540e\u4e0d\u4e00\u5b9a\u4fdd\u7559\u3002 \u901a\u8fc7 SET GLOBAL \u4fee\u6539\u7684\u8bbe\u7f6e\u901a\u5e38\u53ea\u5728\u5f53\u524d\u670d\u52a1\u5668\u8fd0\u884c\u671f\u95f4\u6709\u6548\u3002\u5982\u679c\u5e0c\u671b\u91cd\u542f\u540e\u4ecd\u7136\u751f\u6548，\u9700\u8981\u901a\u8fc7\u914d\u7f6e\u6587\u4ef6\u6216\u9002\u7528\u7684\u6301\u4e45\u5316\u914d\u7f6e\u65b9\u5f0f\u8fdb\u884c\u8bbe\u7f6e\u3002<\/p>\n<\/li>\n

            <\/h4><\/p>\n","protected":false},"excerpt":{"rendered":"

            \u76ee\u5f55 \u672c\u6587\u5185\u5bb9\u6982\u8981
            \n\u4e00\u3001\u8ba4\u8bc6\u4e8b\u52a1
            \n1.1 \u4ec0\u4e48\u662f\u4e8b\u52a1
            \n1.2 \u4e3a\u4ec0\u4e48\u9700\u8981\u4e8b\u52a1
            \n1.3 \u4e8b\u52a1\u7684\u56db\u5927\u7279\u6027（ACID）
            \n1.3.1 \u539f\u5b50\u6027（Atomicity）
            \n1.3.2 \u4e00\u81f4\u6027（Consistency）
            \n1.3.3 \u9694\u79bb\u6027（Isolation）
            \n1.3.4 \u6301\u4e45\u6027（Durability）
            \n\u4e8c\u3001\u4e8b\u52a1\u7684\u57fa\u672c\u64cd\u4f5c
            \n2.1 My<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[11820,114,100],"topic":[],"class_list":["post-120649","post","type-post","status-publish","format-standard","hentry","category-server","tag-atomgit","tag-mysql","tag-100"],"yoast_head":"\nMySQL \u57fa\u7840\u7bc7\uff08\u5341\u4e00\uff09\uff1a\u4e8b\u52a1\u4e0e\u9694\u79bb\u7ea7\u522b - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.wsisp.com\/helps\/120649.html\" \/>\n<meta property=\"og:locale\" content=\"zh_CN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"MySQL \u57fa\u7840\u7bc7\uff08\u5341\u4e00\uff09\uff1a\u4e8b\u52a1\u4e0e\u9694\u79bb\u7ea7\u522b - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3\" \/>\n<meta property=\"og:description\" content=\"\u76ee\u5f55 \u672c\u6587\u5185\u5bb9\u6982\u8981 \u4e00\u3001\u8ba4\u8bc6\u4e8b\u52a1 1.1 \u4ec0\u4e48\u662f\u4e8b\u52a1 1.2 \u4e3a\u4ec0\u4e48\u9700\u8981\u4e8b\u52a1 1.3 \u4e8b\u52a1\u7684\u56db\u5927\u7279\u6027（ACID） 1.3.1 \u539f\u5b50\u6027（Atomicity） 1.3.2 \u4e00\u81f4\u6027（Consistency） 1.3.3 \u9694\u79bb\u6027（Isolation） 1.3.4 \u6301\u4e45\u6027（Durability） \u4e8c\u3001\u4e8b\u52a1\u7684\u57fa\u672c\u64cd\u4f5c 2.1 My\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.wsisp.com\/helps\/120649.html\" \/>\n<meta property=\"og:site_name\" content=\"\u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3\" \/>\n<meta property=\"article:published_time\" content=\"2026-10-31T15:48:28+00:00\" \/>\n<meta name=\"author\" content=\"admin\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"\u4f5c\u8005\" \/>\n\t<meta name=\"twitter:data1\" content=\"admin\" \/>\n\t<meta name=\"twitter:label2\" content=\"\u9884\u8ba1\u9605\u8bfb\u65f6\u95f4\" \/>\n\t<meta name=\"twitter:data2\" content=\"9 \u5206\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.wsisp.com\/helps\/120649.html\",\"url\":\"https:\/\/www.wsisp.com\/helps\/120649.html\",\"name\":\"MySQL \u57fa\u7840\u7bc7\uff08\u5341\u4e00\uff09\uff1a\u4e8b\u52a1\u4e0e\u9694\u79bb\u7ea7\u522b - 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