{"id":118,"date":"2023-11-26T17:34:00","date_gmt":"2023-11-26T09:34:00","guid":{"rendered":"http:\/\/www.cmd137blog.top\/?p=118"},"modified":"2024-04-01T17:37:43","modified_gmt":"2024-04-01T09:37:43","slug":"sql-%e4%ba%8b%e5%8a%a1%ef%bc%88%e4%ba%8b%e5%8a%a1%e6%93%8d%e4%bd%9c%e4%ba%8b%e5%8a%a1%e5%9b%9b%e5%a4%a7%e7%89%b9%e6%80%a7%e5%b9%b6%e5%8f%91%e4%ba%8b%e5%8a%a1%e9%97%ae%e9%a2%98%e4%ba%8b%e5%8a%a1","status":"publish","type":"post","link":"http:\/\/www.cmd137blog.top\/?p=118","title":{"rendered":"SQL-\u4e8b\u52a1\uff08\u4e8b\u52a1\u64cd\u4f5c|\u4e8b\u52a1\u56db\u5927\u7279\u6027|\u5e76\u53d1\u4e8b\u52a1\u95ee\u9898|\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\uff09"},"content":{"rendered":"\n<h1 class=\"wp-block-heading\">\u7b80\u4ecb<\/h1>\n\n\n\n<p><strong>\u4e8b\u52a1<\/strong>\u662f\u4e00\u4e2a\u64cd\u4f5c\u7684\u96c6\u5408\uff0c\u4ed6\u662f\u4e00\u4e2a\u4e0d\u53ef\u5206\u5272\u7684\u5de5\u4f5c\u5355\u4f4d\uff0c\u4e8b\u52a1\u4f1a\u628a\u6240\u6709\u7684\u64cd\u4f5c\u4f5c\u4e3a\u4e00\u4e2a\u6574\u4f53\u4e00\u8d77\u5411\u7cfb\u7edf\u63d0\u4ea4\u6216\u64a4\u9500\u64cd\u4f5c\u8bf7\u6c42\uff0c\u5373\u8fd9\u4e9b\u64cd\u4f5c<strong>\u8981\u4e48\u540c\u65f6\u6210\u529f\u8981\u4e48\u540c\u65f6\u5931\u8d25<\/strong>\u3002<br>\u4f8b\uff1a\u5f20\u4e09\u8981\u5411\u674e\u56db\u8f6c\u8d261000\uff1a<br><br>\u9ed8\u8ba4MySQL\u7684\u4e8b\u52a1\u662f\u81ea\u52a8\u63d0\u4ea4\u7684\uff0c\u5373\u5f53\u6267\u884c\u4e00\u6761DML\u8bed\u53e5\uff0cMySQL\u4f1a\u7acb\u5373\u9690\u5f0f\u7684\u63d0\u4ea4\u4e8b\u52a1\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='http:\/\/www.cmd137blog.top\/wp-content\/uploads\/2024\/04\/d4daa631f40643d68dd219650dba29a0.png'><img class=\"lazyload lazyload-style-1\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  loading=\"lazy\" decoding=\"async\" width=\"595\" height=\"380\" data-original=\"http:\/\/www.cmd137blog.top\/wp-content\/uploads\/2024\/04\/d4daa631f40643d68dd219650dba29a0.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" class=\"wp-image-119\"  sizes=\"auto, (max-width: 595px) 100vw, 595px\" \/><\/div><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u4e00\u3001\u4e8b\u52a1\u64cd\u4f5c<\/h1>\n\n\n\n<p>\u6a21\u62df\u8f6c\u8d26\u64cd\u4f5c\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>-- 1. \u67e5\u8be2\u5f20\u4e09\u8d26\u6237\u4f59\u989d\nselect * from account where name = '\u5f20\u4e09';\n-- 2. \u5c06\u5f20\u4e09\u8d26\u6237\u4f59\u989d-1000\nupdate account set money = money - 1000 where name = '\u5f20\u4e09';\n-- \u6b64\u8bed\u53e5\u51fa\u9519\u540e\u5f20\u4e09\u94b1\u51cf\u5c11\u4f46\u662f\u674e\u56db\u94b1\u6ca1\u6709\u589e\u52a0\n\u6a21\u62dfsql\u8bed\u53e5\u9519\u8bef...\n-- 3. \u5c06\u674e\u56db\u8d26\u6237\u4f59\u989d+1000\nupdate account set money = money + 1000 where name = '\u674e\u56db';<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u65b9\u6cd5\u4e00\uff1a\u4fee\u6539\u4e8b\u52a1\u63d0\u4ea4\u65b9\u5f0f\uff1a<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u67e5\u770b\u5f53\u524d\u4e8b\u52a1\u63d0\u4ea4\u65b9\u5f0f\uff1a1\u8868\u793a\u81ea\u52a8\u63d0\u4ea4\uff0c0\u8868\u793a\u624b\u52a8\u63d0\u4ea4\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>SELECT @@AUTOCOMMIT;<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u8bbe\u7f6e\u4e8b\u52a1\u63d0\u4ea4\u65b9\u5f0f\uff1a1\u4e3a\u81ea\u52a8\u63d0\u4ea4\uff0c0\u4e3a\u624b\u52a8\u63d0\u4ea4\uff0c\u8be5\u8bbe\u7f6e\u53ea\u5bf9\u5f53\u524d\u4f1a\u8bdd\u6709\u6548\uff1a<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>SET @@AUTOCOMMIT = 0;<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u63d0\u4ea4\u4e8b\u52a1\uff1a<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>COMMIT;<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u56de\u6eda\u4e8b\u52a1\uff1a<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>ROLLBACK;<\/code><\/pre>\n\n\n\n<p>\u5219\u4e0a\u9762\u4ee3\u7801\u53ef\u6539\u4e3a\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>select * from account where name = '\u5f20\u4e09';\nupdate account set money = money - 1000 where name = '\u5f20\u4e09';\nupdate account set money = money + 1000 where name = '\u674e\u56db';\ncommit;\n--\u82e5\u6267\u884c\u5931\u8d25\uff1a\n--ROLLBACK;<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u65b9\u6cd5\u4e8c\uff1a\u5f00\u542f\u4e8b\u52a1\u2014&gt;\u63d0\u4ea4\u4e8b\u52a1\uff1a<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5f00\u542f\u4e8b\u52a1\uff1a<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>START TRANSACTION; \u6216 BEGIN TRANSACTION;<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u63d0\u4ea4\u4e8b\u52a1\uff1a<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>COMMIT;<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u56de\u6eda\u4e8b\u52a1\uff1a<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>ROLLBACK;<\/code><\/pre>\n\n\n\n<p>\u5219\u4e0a\u9762\u4ee3\u7801\u53ef\u6539\u4e3a\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>START TRANSACTION;\nSELECT * FROM account WHERE name = '\u5f20\u4e09';\nUPDATE account set money = money-1000 where name ='\u5f20\u4e09';\nUPDATE account set money = money+1000 where name ='\u674e\u56db';\nCOMMIT;\n--\u82e5\u6267\u884c\u5931\u8d25\uff1a\n--ROLLBACK;<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u4e8c\u3001\u4e8b\u52a1\u56db\u5927\u7279\u6027:ACID<\/h1>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u539f\u5b50\u6027(Atomicity)\uff1a\u4e8b\u52a1\u662f\u4e0d\u53ef\u5206\u5272\u7684\u6700\u5c0f\u64cd\u4f5c\u5355\u5143\uff0c\u8981\u5417\u5168\u90e8\u6210\u529f\uff0c\u8981\u5417\u5168\u90e8\u5931\u8d25\uff1b<\/li>\n\n\n\n<li>\u4e00\u81f4\u6027(Consistency)\uff1a\u4e8b\u52a1\u5b8c\u6210\u65f6\uff0c\u5fc5\u987b\u4f7f\u6240\u6709\u7684\u6570\u636e\u4fdd\u6301\u4e00\u81f4\u72b6\u6001\uff1b<\/li>\n\n\n\n<li>\u9694\u79bb\u6027(Isolation)\uff1a\u6570\u636e\u5e93\u7cfb\u7edf\u63d0\u4f9b\u7684\u9694\u79bb\u673a\u5236\uff0c\u4fdd\u8bc1\u4e8b\u52a1\u4e0d\u53d7\u5916\u90e8\u5e76\u53d1\u64cd\u4f5c\u5f71\u54cd\u7684\u72ec\u7acb\u73af\u5883\u4e0b\u8fd0\u884c\uff1b<\/li>\n\n\n\n<li>\u6301\u4e45\u6027(Durability)\uff1a\u4e8b\u52a1\u4e00\u65e6\u63d0\u4ea4\u6216\u56de\u6eda\uff0c\u5b83\u5bf9\u6570\u636e\u5e93\u4e2d\u6570\u636e\u7684\u6539\u53d8\u65f6\u6c38\u4e45\u7684\u3002<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h1 class=\"wp-block-heading\">\u4e09\u3001\u5e76\u53d1\u4e8b\u52a1\u95ee\u9898<\/h1>\n\n\n\n<p>\u5e76\u53d1\u4e8b\u52a1\u95ee\u9898\uff1aA\u4e8b\u52a1B\u4e8b\u52a1\u5728\u540c\u65f6\u64cd\u4f5c\u67d0\u4e00\u6570\u636e\u5e93\/\u8868\u65f6\u5f15\u53d1\u7684\u95ee\u9898\u3002<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>\u95ee\u9898<\/th><th>\u63cf\u8ff0<\/th><\/tr><\/thead><tbody><tr><td>\u810f\u8bfb<\/td><td>\u4e00\u4e2a\u4e8b\u7269\u8bfb\u5230\u53e6\u4e00\u4e2a\u4e8b\u52a1\u8fd8\u6ca1\u6709\u63d0\u4ea4\u7684\u6570\u636e<\/td><\/tr><tr><td>\u4e0d\u53ef\u91cd\u590d\u8bfb<\/td><td>\u4e00\u4e2a\u4e8b\u52a1\u5148\u540e\u8bfb\u53d6\u540c\u4e00\u6761\u8bb0\u5f55\uff0c\u4f46\u4e24\u6b21\u8bfb\u53d6\u7684\u6570\u636e\u4e0d\u540c<\/td><\/tr><tr><td>\u5e7b\u8bfb<\/td><td>\u4e00\u4e2a\u4e8b\u7269\u6309\u7167\u6761\u4ef6\u67e5\u8be2\u6570\u636e\u65f6\uff0c\u6ca1\u6709\u5bf9\u5e94\u7684\u6570\u636e\u884c\uff0c\u4f46\u662f\u5728\u63d2\u5165\u6570\u636e\u65f6\uff0c\u53c8\u53d1\u73b0\u8fd9\u884c\u6570\u636e\u5df2\u7ecf\u5b58\u5728<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">1.\u810f\u8bfb\uff1a<\/h2>\n\n\n\n<p>\u810f\u8bfb\u662f\u6307\u4e00\u4e2a\u4e8b\u52a1\u5728\u8bfb\u53d6\u4e86\u53e6\u4e00\u4e2a\u4e8b\u52a1\u5c1a\u672a\u63d0\u4ea4\u7684\u6570\u636e\u65f6\u53d1\u751f\u7684\u73b0\u8c61\u3002\u5047\u8bbe\u6709\u4e24\u4e2a\u5e76\u53d1\u7684\u4e8b\u52a1 A \u548c\u4e8b\u52a1 B\uff0c\u4e8b\u52a1 A \u5728\u8bfb\u53d6\u6570\u636e\u7684\u540c\u65f6\uff0c\u4e8b\u52a1 B \u5bf9\u8be5\u6570\u636e\u505a\u4e86\u4fee\u6539\uff0c\u5e76\u4e14\u8fd8\u6ca1\u6709\u63d0\u4ea4\u3002\u5982\u679c\u4e8b\u52a1 A \u8bfb\u53d6\u4e86\u8fd9\u4e2a\u672a\u63d0\u4ea4\u7684\u6570\u636e\uff0c\u5c31\u53d1\u751f\u4e86\u810f\u8bfb\u3002<\/p>\n\n\n\n<p>\u4e3e\u4f8b\uff1a<br>\u5047\u8bbe\u7528\u6237 A \u7684\u8d26\u6237\u4f59\u989d\u4e3a 1000 \u5143\uff0c\u7528\u6237 B \u7684\u8d26\u6237\u4f59\u989d\u4e3a 2000 \u5143\u3002\u4e8b\u52a1 A \u5728\u8bfb\u53d6\u7528\u6237 A \u7684\u4f59\u989d\u65f6\uff0c\u7528\u6237 B \u540c\u65f6\u8fdb\u884c\u4e86\u4e00\u7b14\u8f6c\u8d26\u64cd\u4f5c\u5c06\u81ea\u5df1\u7684\u4f59\u989d\u51cf\u5c11\u5230 1000 \u5143\uff0c\u5e76\u63d0\u4ea4\u4e86\u4e8b\u52a1\u3002\u6b64\u65f6\u4e8b\u52a1 A \u8bfb\u53d6\u5230\u7684\u7528\u6237 A \u7684\u4f59\u989d\u662f 1000 \u5143\uff0c\u4f46\u5b9e\u9645\u4e0a\u7528\u6237 A \u7684\u4f59\u989d\u8fd8\u662f 2000 \u5143\u3002\u8fd9\u5c31\u662f\u4e00\u4e2a\u810f\u8bfb\u73b0\u8c61\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">2.\u4e0d\u53ef\u91cd\u590d\u8bfb\uff1a<\/h2>\n\n\n\n<p>\u4e0d\u53ef\u91cd\u590d\u8bfb\u662f\u6307\u4e00\u4e2a\u4e8b\u52a1\u5728\u8bfb\u53d6\u4e86\u67d0\u4e2a\u6570\u636e\u540e\uff0c\u518d\u6b21\u8bfb\u53d6\u8be5\u6570\u636e\u65f6\uff0c\u53d1\u73b0\u6570\u636e\u5df2\u7ecf\u53d1\u751f\u4e86\u53d8\u5316\u3002\u8fd9\u662f\u56e0\u4e3a\u5728\u8be5\u4e8b\u52a1\u8bfb\u53d6\u6570\u636e\u671f\u95f4\uff0c\u53e6\u4e00\u4e2a\u4e8b\u52a1\u5bf9\u8be5\u6570\u636e\u8fdb\u884c\u4e86\u4fee\u6539\u5e76\u63d0\u4ea4\uff0c\u5bfc\u81f4\u4e24\u6b21\u8bfb\u53d6\u7684\u7ed3\u679c\u4e0d\u4e00\u81f4\u3002<\/p>\n\n\n\n<p>\u4e3e\u4f8b\uff1a<br>\u5047\u8bbe\u4e8b\u52a1 A \u5728\u8bfb\u53d6\u67d0\u4e2a\u8868\u4e2d\u7684\u4e00\u6761\u8bb0\u5f55\u65f6\uff0c\u5f97\u5230\u4e86\u8be5\u8bb0\u5f55\u7684\u67d0\u4e2a\u7279\u5b9a\u503c\u3002\u800c\u5728\u4e8b\u52a1 A \u8fdb\u884c\u5176\u4ed6\u64cd\u4f5c\u7684\u8fc7\u7a0b\u4e2d\uff0c\u4e8b\u52a1 B \u4fee\u6539\u4e86\u8be5\u8bb0\u5f55\u5e76\u63d0\u4ea4\u4e86\u4e8b\u52a1\u3002\u6b64\u65f6\uff0c\u4e8b\u52a1 A \u518d\u6b21\u8bfb\u53d6\u8be5\u8bb0\u5f55\u65f6\uff0c\u53d1\u73b0\u8be5\u8bb0\u5f55\u7684\u503c\u5df2\u7ecf\u53d1\u751f\u4e86\u53d8\u5316\uff0c\u5bfc\u81f4\u4e0d\u53ef\u91cd\u590d\u8bfb\u7684\u73b0\u8c61\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">3.\u5e7b\u8bfb\uff1a<\/h2>\n\n\n\n<p>\u5e7b\u8bfb\u662f\u6307\u4e00\u4e2a\u4e8b\u52a1\u5728\u8bfb\u53d6\u67d0\u4e2a\u8303\u56f4\u5185\u7684\u6570\u636e\u8bb0\u5f55\u65f6\uff0c\u53d1\u73b0\u6709\u65b0\u7684\u6570\u636e\u8bb0\u5f55\u88ab\u63d2\u5165\uff0c\u5bfc\u81f4\u4e24\u6b21\u8bfb\u53d6\u7684\u8bb0\u5f55\u6570\u4e0d\u4e00\u81f4\u3002<em>\u5e7b\u8bfb\u4e0e\u4e0d\u53ef\u91cd\u590d\u8bfb\u7684\u533a\u522b\u5728\u4e8e\uff0c\u5e7b\u8bfb\u91cd\u70b9\u5173\u6ce8\u7684\u662f\u65b0\u589e\u7684\u6570\u636e\u8bb0\u5f55\uff0c\u800c\u4e0d\u662f\u5df2\u6709\u7684\u6570\u636e\u8bb0\u5f55\u7684\u66f4\u65b0\u3002<\/em><\/p>\n\n\n\n<p>\u4e3e\u4f8b\uff1a<br>\u5047\u8bbe\u4e8b\u52a1 A \u5728\u67d0\u4e2a\u8868\u4e2d\u6309\u67d0\u4e2a\u6761\u4ef6\u8bfb\u53d6\u4e86\u4e00\u6279\u6570\u636e\u8bb0\u5f55\uff0c\u7136\u540e\u5728\u4e8b\u52a1 A \u8fdb\u884c\u5176\u4ed6\u64cd\u4f5c\u7684\u8fc7\u7a0b\u4e2d\uff0c\u4e8b\u52a1 B \u63d2\u5165\u4e86\u4e00\u4e9b\u7b26\u5408\u6761\u4ef6\u7684\u65b0\u6570\u636e\u8bb0\u5f55\uff0c\u5e76\u63d0\u4ea4\u4e86\u4e8b\u52a1\u3002\u6b64\u65f6\u4e8b\u52a1 A \u518d\u6b21\u6309\u7167\u540c\u6837\u7684\u6761\u4ef6\u8bfb\u53d6\u6570\u636e\u65f6\uff0c\u53d1\u73b0\u6709\u65b0\u589e\u6570\u636e\u8bb0\u5f55\u51fa\u73b0\uff0c\u5bfc\u81f4\u5e7b\u8bfb\u7684\u73b0\u8c61\u3002<\/p>\n\n\n\n<h1 class=\"wp-block-heading\">\u56db\u3001\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\uff1a<\/h1>\n\n\n\n<p>\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u5b9a\u4e49\u4e86\u4e8b\u52a1\u5728\u5e76\u53d1\u6267\u884c\u65f6\uff0c\u5bf9\u5176\u4ed6\u4e8b\u52a1\u64cd\u4f5c\u7684\u53ef\u89c1\u6027\u548c\u5f71\u54cd\u7684\u9650\u5236\u7a0b\u5ea6\u3002\u6807\u51c6\u7684 SQL \u89c4\u8303\u5b9a\u4e49\u4e86\u56db\u79cd\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\uff1a<br><em>\u53e6\u5916\uff0cMySQL\u7684\u9ed8\u8ba4\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u4e3a \u53ef\u91cd\u590d\u8bfb\uff08Repeatable Read\uff09\u3002<\/em><\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>\u9694\u79bb\u7ea7\u522b<\/th><th>\u810f\u8bfb<\/th><th>\u4e0d\u53ef\u91cd\u590d\u8bfb<\/th><th>\u5e7b\u8bfb<\/th><\/tr><\/thead><tbody><tr><td>\u8bfb\u672a\u63d0\u4ea4\uff08Read Uncommitted\uff09<\/td><td>\u221a<\/td><td>\u221a<\/td><td>\u221a<\/td><\/tr><tr><td>\u8bfb\u5df2\u63d0\u4ea4\uff08Read Committed\uff09<\/td><td>\u00d7<\/td><td>\u221a<\/td><td>\u221a<\/td><\/tr><tr><td>\u53ef\u91cd\u590d\u8bfb\uff08Repeatable Read\uff09<\/td><td>\u00d7<\/td><td>\u00d7<\/td><td>\u221a<\/td><\/tr><tr><td>\u4e32\u884c\u5316\uff08Serializable\uff09<\/td><td>\u00d7<\/td><td>\u00d7<\/td><td>\u00d7<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u221a\u8868\u793a\u5728\u5f53\u524d\u9694\u79bb\u7ea7\u522b\u4e0b\u8be5\u95ee\u9898\u4f1a\u51fa\u73b0<\/li>\n\n\n\n<li>Serializable \u6027\u80fd\u6700\u4f4e\uff1bRead uncommitted \u6027\u80fd\u6700\u9ad8\uff0c\u6570\u636e\u5b89\u5168\u6027\u6700\u5dee<\/li>\n\n\n\n<li>\u67e5\u770b\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\uff1a<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>SELECT @@TRANSACTION_ISOLATION;<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u8bbe\u7f6e\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\uff1a\uff08SESSION \u662f\u4f1a\u8bdd\u7ea7\u522b\uff0c\u8868\u793a\u53ea\u9488\u5bf9\u5f53\u524d\u4f1a\u8bdd\u6709\u6548\uff0cGLOBAL \u8868\u793a\u5bf9\u6240\u6709\u4f1a\u8bdd\u6709\u6548\uff09<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>SET &#91; SESSION | GLOBAL ] \nTRANSACTION ISOLATION LEVEL \n{READ UNCOMMITTED | READ COMMITTED | REPEATABLE READ | SERIALIZABLE };<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">1.\u8bfb\u672a\u63d0\u4ea4\uff08Read Uncommitted\uff09\uff1a<\/h2>\n\n\n\n<p>\u8be5\u9694\u79bb\u7ea7\u522b\u5141\u8bb8\u4e00\u4e2a\u4e8b\u52a1\u8bfb\u53d6\u53e6\u4e00\u4e2a\u672a\u63d0\u4ea4\u7684\u4e8b\u52a1\u6240\u505a\u7684\u4fee\u6539\uff0c\u53ef\u4ee5\u53d1\u751f\u810f\u8bfb\u3001\u4e0d\u53ef\u91cd\u590d\u8bfb\u548c\u5e7b\u8bfb\u7684\u95ee\u9898\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">2.\u8bfb\u5df2\u63d0\u4ea4\uff08Read Committed\uff09\uff1a<\/h2>\n\n\n\n<p>\u8be5\u9694\u79bb\u7ea7\u522b\u8981\u6c42\u4e00\u4e2a\u4e8b\u52a1\u53ea\u80fd\u8bfb\u53d6\u5df2\u7ecf\u63d0\u4ea4\u7684\uff0c\u4f46\u662f\u53ef\u80fd\u4f1a\u53d1\u751f\u4e0d\u53ef\u91cd\u590d\u8bfb\u548c\u5e7b\u8bfb\u7684\u95ee\u9898\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">3.\u53ef\u91cd\u590d\u8bfb\uff08Repeatable Read\uff09\uff1a<\/h2>\n\n\n\n<p>\u8be5\u9694\u79bb\u7ea7\u522b\u8981\u6c42\u4e00\u4e2a\u4e8b\u52a1\u53ea\u80fd\u8bfb\u53d6\u5df2\u7ecf\u63d0\u4ea4\u7684\u6570\u636e\uff0c\u5e76\u4e14\u5728\u540c\u4e00\u4e8b\u52a1\u4e2d\u591a\u6b21\u8bfb\u53d6\u540c\u6837\u7684\u6570\u636e\uff0c\u5f97\u5230\u7684\u7ed3\u679c\u662f\u4e00\u81f4\u7684\u3002\u4f46\u662f\u4ecd\u7136\u53ef\u80fd\u4f1a\u53d1\u751f\u5e7b\u8bfb\u7684\u95ee\u9898\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">4.\u4e32\u884c\u5316\uff08Serializable\uff09 \uff1a<\/h2>\n\n\n\n<p>\u8be5\u9694\u79bb\u7ea7\u522b\u9650\u5236\u4e86\u540c\u65f6\u6267\u884c\u7684\u4e8b\u52a1\u4e4b\u95f4\u4e92\u76f8\u8bbf\u95ee\u6570\u636e\u7684\u80fd\u529b\uff0c\u53ea\u6709\u4e00\u6761\u4e8b\u52a1\u53ef\u4ee5\u5bf9\u6570\u636e\u8fdb\u884c\u8bfb\u5199\uff0c\u907f\u514d\u4e86\u6240\u6709\u7684\u5e76\u53d1\u95ee\u9898\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p>\u4e00\u822c\u6765\u8bf4\uff0c\u9694\u79bb\u7ea7\u522b\u8d8a\u9ad8\uff0c\u4fdd\u8bc1\u6570\u636e\u7684\u4e00\u81f4\u6027\u5c31\u8d8a\u597d\uff0c\u4f46\u662f\u5bf9\u7cfb\u7edf\u7684\u6027\u80fd\u5f71\u54cd\u4e5f\u8d8a\u5927\u3002\u56e0\u6b64\uff0c\u5728\u9009\u62e9\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u65f6\uff0c\u9700\u8981\u6839\u636e\u5177\u4f53\u4e1a\u52a1\u573a\u666f\u548c\u7cfb\u7edf\u8d1f\u8f7d\u60c5\u51b5\u8fdb\u884c\u8003\u8651\u548c\u53d6\u820d\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u7b80\u4ecb \u4e8b\u52a1\u662f\u4e00\u4e2a\u64cd\u4f5c\u7684\u96c6\u5408\uff0c\u4ed6\u662f\u4e00\u4e2a\u4e0d\u53ef\u5206\u5272\u7684\u5de5\u4f5c\u5355\u4f4d\uff0c\u4e8b\u52a1\u4f1a\u628a\u6240\u6709\u7684\u64cd\u4f5c\u4f5c\u4e3a\u4e00\u4e2a\u6574\u4f53\u4e00\u8d77\u5411\u7cfb\u7edf\u63d0\u4ea4\u6216\u64a4\u9500\u64cd\u4f5c [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[14,20],"class_list":["post-118","post","type-post","status-publish","format-standard","hentry","category-sql","tag-sql","tag-20"],"_links":{"self":[{"href":"http:\/\/www.cmd137blog.top\/index.php?rest_route=\/wp\/v2\/posts\/118","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.cmd137blog.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.cmd137blog.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.cmd137blog.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.cmd137blog.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=118"}],"version-history":[{"count":1,"href":"http:\/\/www.cmd137blog.top\/index.php?rest_route=\/wp\/v2\/posts\/118\/revisions"}],"predecessor-version":[{"id":120,"href":"http:\/\/www.cmd137blog.top\/index.php?rest_route=\/wp\/v2\/posts\/118\/revisions\/120"}],"wp:attachment":[{"href":"http:\/\/www.cmd137blog.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=118"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.cmd137blog.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=118"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.cmd137blog.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=118"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}