{"id":4730,"date":"2020-02-06T10:30:12","date_gmt":"2020-02-06T02:30:12","guid":{"rendered":"https:\/\/www.xttblog.com\/?p=4730"},"modified":"2020-02-06T10:30:12","modified_gmt":"2020-02-06T02:30:12","slug":"mysql-%e6%9c%80%e6%96%b0%e9%ab%98%e9%a2%91%e9%9d%a2%e8%af%95%e9%a2%98","status":"publish","type":"post","link":"https:\/\/www.xttblog.com\/?p=4730","title":{"rendered":"MySQL \u6700\u65b0\u9ad8\u9891\u9762\u8bd5\u9898"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">\u53c8\u5230\u4e86\u4e00\u5e74\u7684\u9762\u8bd5\u5b63\uff0c\u4eca\u5e74\u60c5\u51b5\u7279\u6b8a\uff0c\u5f88\u591a\u4eba\u53ef\u80fd\u90fd\u7a9d\u5728\u5bb6\u91cc\uff0c\u4e5f\u6709\u4e00\u4e9b\u4eba\u51c6\u5907\u627e\u5de5\u4f5c\uff0c\u4f46\u662f\u75ab\u60c5\u4e25\u91cd\uff0c\u4e5f\u6ca1\u4f01\u4e1a\u53d1\u62db\u8058\u4fe1\u606f\u3002\u8fd9\u4e2a\u65f6\u5019\uff0c\u6700\u597d\u7684\u505a\u6cd5\u5c31\u662f\u5728\u5bb6\u91cc\u5237\u9762\u8bd5\u9898\uff0c\u4eca\u5929\u7ed9\u5927\u5bb6\u5206\u4eab 21 \u4e2a MySQL \u9762\u8bd5\u9898\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">1\u3001Mysql\u4e2d\u6709\u54ea\u51e0\u79cd\u9501\uff1f<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">MyISAM \u652f\u6301\u8868\u9501\uff0cInnoDB \u652f\u6301\u8868\u9501\u548c\u884c\u9501\uff0c\u9ed8\u8ba4\u4e3a\u884c\u9501\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u8868\u7ea7\u9501:\u5f00\u9500\u5c0f\uff0c\u52a0\u9501\u5feb\uff0c\u4e0d\u4f1a\u51fa\u73b0\u6b7b\u9501\u3002\u9501\u5b9a\u7c92\u5ea6\u5927\uff0c\u53d1\u751f\u9501\u51b2\u7a81\u7684\u6982\u7387\u6700\u9ad8\uff0c\u5e76\u53d1\u91cf \u6700\u4f4e\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u884c\u7ea7\u9501:\u5f00\u9500\u5927\uff0c\u52a0\u9501\u6162\uff0c\u4f1a\u51fa\u73b0\u6b7b\u9501\u3002\u9501\u529b\u5ea6\u5c0f\uff0c\u53d1\u751f\u9501\u51b2\u7a81\u7684\u6982\u7387\u5c0f\uff0c\u5e76\u53d1\u5ea6\u6700\u9ad8\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">2\u3001Mysql\u652f\u6301\u4e8b\u52a1\u5417\uff1f<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5728\u7f3a\u7701\u6a21\u5f0f\u4e0b\uff0cMYSQL \u662f autocommit \u6a21\u5f0f\u7684\uff0c\u6240\u6709\u7684\u6570\u636e\u5e93\u66f4\u65b0\u64cd\u4f5c\u90fd\u4f1a\u5373\u65f6\u63d0\u4ea4\uff0c\u6240 \u4ee5\u5728\u7f3a\u7701\u60c5\u51b5\u4e0b\uff0cmysql \u662f\u4e0d\u652f\u6301\u4e8b\u52a1\u7684\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f46\u662f\u5982\u679c\u4f60\u7684 MYSQL \u8868\u7c7b\u578b\u662f\u4f7f\u7528 InnoDB Tables \u6216 BDB tables \u7684\u8bdd\uff0c\u4f60\u7684 MYSQL \u5c31\u53ef\u4ee5 \u4f7f\u7528\u4e8b\u52a1\u5904\u7406,\u4f7f\u7528 SET AUTOCOMMIT=0 \u5c31\u53ef\u4ee5\u4f7f MYSQL \u5141\u8bb8\u5728\u975e autocommit \u6a21\u5f0f\uff0c\u5728\u975eautocommit \u6a21\u5f0f\u4e0b\uff0c\u4f60\u5fc5\u987b\u4f7f\u7528 COMMIT \u6765\u63d0\u4ea4\u4f60\u7684\u66f4\u6539\uff0c\u6216\u8005\u7528 ROLLBACK \u6765\u56de\u6eda\u4f60\u7684 \u66f4\u6539\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u793a\u4f8b\u5982\u4e0b\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>START TRANSACTION;\nSELECT @A:=SUM(salary) FROM table1 WHERE type=1; \nUPDATE table2 SET summmary=@A WHERE type=1; \nCOMMIT;<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">3\u3001Mysql\u67e5\u8be2\u662f\u5426\u533a\u5206\u5927\u5c0f\u5199\uff1f<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e0d\u533a\u5206\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>SELECT VERSION(), CURRENT_DATE;\nSeLect version(), current_date;\nseleCt vErSiOn(), current_DATE;<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u8fd9\u51e0\u4e2a\u4f8b\u5b50\u90fd\u662f\u4e00\u6837\u7684\uff0cMysql \u4e0d\u533a\u5206\u5927\u5c0f\u5199\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">4\u3001\u5217\u8bbe\u7f6e\u4e3a AUTO INCREMENT \u65f6\uff0c\u5982\u679c\u5728\u8868\u4e2d\u8fbe\u5230\u6700\u5927\u503c\uff0c\u4f1a\u53d1\u751f\u4ec0\u4e48\u60c5\u51b5?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b54\uff1a\u5b83\u4f1a\u505c\u6b62\u9012\u589e\uff0c\u4efb\u4f55\u8fdb\u4e00\u6b65\u7684\u63d2\u5165\u90fd\u5c06\u4ea7\u751f\u9519\u8bef\uff0c\u56e0\u4e3a\u5bc6\u94a5\u5df2\u88ab\u4f7f\u7528\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">5\u3001\u4e00\u5f20\u8868\uff0c\u91cc\u9762\u6709 ID \u81ea\u589e\u4e3b\u952e\uff0c\u5f53 insert \u4e86 17 \u6761\u8bb0\u5f55\u4e4b\u540e\uff0c\u5220\u9664\u4e86\u7b2c 15,16,17 \u6761\u8bb0\u5f55\uff0c \u518d\u628a Mysql \u91cd\u542f\uff0c\u518d insert \u4e00\u6761\u8bb0\u5f55\uff0c\u8fd9\u6761\u8bb0\u5f55\u7684 ID \u662f 18 \u8fd8\u662f 15 ?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5982\u679c\u8868\u7684\u7c7b\u578b\u662f MyISAM\uff0c\u90a3\u4e48\u662f 18\u3002\u56e0\u4e3a MyISAM \u8868\u4f1a\u628a\u81ea\u589e\u4e3b\u952e\u7684\u6700\u5927 ID \u8bb0\u5f55\u5230\u6570\u636e\u6587\u4ef6\u91cc\uff0c\u91cd\u542f MySQL \u81ea\u589e\u4e3b\u952e\u7684\u6700\u5927ID \u4e5f\u4e0d\u4f1a\u4e22\u5931\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5982\u679c\u8868\u7684\u7c7b\u578b\u662f InnoDB\uff0c\u90a3\u4e48\u662f 15\u3002InnoDB \u8868\u53ea\u662f\u628a\u81ea\u589e\u4e3b\u952e\u7684\u6700\u5927 ID \u8bb0\u5f55\u5230\u5185\u5b58\u4e2d\uff0c\u6240\u4ee5\u91cd\u542f\u6570\u636e\u5e93\u6216\u8005\u662f\u5bf9\u8868\u8fdb\u884cOPTIMIZE \u64cd\u4f5c\uff0c\u90fd\u4f1a\u5bfc\u81f4\u6700\u5927 ID \u4e22\u5931\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">6\u3001\u6570\u636e\u5e93\u4e09\u8303\u5f0f\u662f\u4ec0\u4e48?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b2c\u4e00\u8303\u5f0f(1NF):\u5b57\u6bb5\u5177\u6709\u539f\u5b50\u6027,\u4e0d\u53ef\u518d\u5206\u3002(\u6240\u6709\u5173\u7cfb\u578b\u6570\u636e\u5e93\u7cfb \u7edf\u90fd\u6ee1\u8db3\u7b2c\u4e00\u8303\u5f0f\u6570\u636e\u5e93\u8868\u4e2d\u7684\u5b57\u6bb5\u90fd\u662f\u5355\u4e00\u5c5e\u6027\u7684\uff0c\u4e0d\u53ef\u518d\u5206) <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b2c\u4e8c\u8303\u5f0f(2NF)\u662f\u5728\u7b2c\u4e00\u8303\u5f0f(1NF)\u7684\u57fa\u7840\u4e0a\u5efa\u7acb\u8d77\u6765\u7684\uff0c\u5373\u6ee1\u8db3 \u7b2c\u4e8c\u8303\u5f0f(2NF)\u5fc5\u987b\u5148\u6ee1\u8db3\u7b2c\u4e00\u8303\u5f0f(1NF)\u3002\u8981\u6c42\u6570\u636e\u5e93\u8868\u4e2d\u7684\u6bcf \u4e2a\u5b9e\u4f8b\u6216\u884c\u5fc5\u987b\u53ef\u4ee5\u88ab\u60df\u4e00\u5730\u533a\u5206\u3002\u901a\u5e38\u9700\u8981\u4e3a\u8868\u52a0\u4e0a\u4e00\u4e2a\u5217\uff0c\u4ee5\u5b58\u50a8 \u5404\u4e2a\u5b9e\u4f8b\u7684\u60df\u4e00\u6807\u8bc6\u3002\u8fd9\u4e2a\u60df\u4e00\u5c5e\u6027\u5217\u88ab\u79f0\u4e3a\u4e3b\u5173\u952e\u5b57\u6216\u4e3b\u952e\u3002 <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6ee1\u8db3\u7b2c\u4e09\u8303\u5f0f(3NF)\u5fc5\u987b\u5148\u6ee1\u8db3\u7b2c\u4e8c\u8303\u5f0f(2NF)\u3002\u7b80\u800c\u8a00\u4e4b\uff0c\u7b2c\u4e09 \u8303\u5f0f(3NF)\u8981\u6c42\u4e00\u4e2a\u6570\u636e\u5e93\u8868\u4e2d\u4e0d\u5305\u542b\u5df2\u5728\u5176\u5b83\u8868\u4e2d\u5df2\u5305\u542b\u7684\u975e\u4e3b\u5173 \u952e\u5b57\u4fe1\u606f\u3002&gt;\u6240\u4ee5\u7b2c\u4e09\u8303\u5f0f\u5177\u6709\u5982\u4e0b\u7279\u5f81: &gt;&gt;1. \u6bcf\u4e00\u5217\u53ea\u6709\u4e00\u4e2a \u503c &gt;&gt;2. \u6bcf\u4e00\u884c\u90fd\u80fd\u533a\u5206\u3002&gt;&gt;3. \u6bcf\u4e00\u4e2a\u8868\u90fd\u4e0d\u5305\u542b\u5176\u4ed6\u8868\u5df2\u7ecf\u5305\u542b \u7684\u975e\u4e3b\u5173\u952e\u5b57\u4fe1\u606f\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">7\u3001mysql \u7684\u590d\u5236\u539f\u7406\u4ee5\u53ca\u6d41\u7a0b\uff1f<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b54\uff1aMysql \u5185\u5efa\u7684\u590d\u5236\u529f\u80fd\u662f\u6784\u5efa\u5927\u578b\uff0c\u9ad8\u6027\u80fd\u5e94\u7528\u7a0b\u5e8f\u7684\u57fa\u7840\u3002\u5c06 Mysql \u7684\u6570\u636e \u5206\u5e03\u5230\u591a\u4e2a\u7cfb\u7edf\u4e0a\u53bb\uff0c\u8fd9\u79cd\u5206\u5e03\u7684\u673a\u5236\uff0c\u662f\u901a\u8fc7\u5c06 Mysql \u7684\u67d0\u4e00\u53f0\u4e3b\u673a\u7684\u6570\u636e \u590d\u5236\u5230\u5176\u5b83\u4e3b\u673a(slaves)\u4e0a\uff0c\u5e76\u91cd\u65b0\u6267\u884c\u4e00\u904d\u6765\u5b9e\u73b0\u7684\u3002* \u590d\u5236\u8fc7\u7a0b\u4e2d\u4e00 \u4e2a\u670d\u52a1\u5668\u5145\u5f53\u4e3b\u670d\u52a1\u5668\uff0c\u800c\u4e00\u4e2a\u6216\u591a\u4e2a\u5176\u5b83\u670d\u52a1\u5668\u5145\u5f53\u4ece\u670d\u52a1\u5668\u3002\u4e3b\u670d\u52a1\u5668\u5c06 \u66f4\u65b0\u5199\u5165\u4e8c\u8fdb\u5236\u65e5\u5fd7\u6587\u4ef6\uff0c\u5e76\u7ef4\u62a4\u6587\u4ef6\u7684\u4e00\u4e2a\u7d22\u5f15\u4ee5\u8ddf\u8e2a\u65e5\u5fd7\u5faa\u73af\u3002\u8fd9\u4e9b\u65e5\u5fd7 \u53ef\u4ee5\u8bb0\u5f55\u53d1\u9001\u5230\u4ece\u670d\u52a1\u5668\u7684\u66f4\u65b0\u3002\u5f53\u4e00\u4e2a\u4ece\u670d\u52a1\u5668\u8fde\u63a5\u4e3b\u670d\u52a1\u5668\u65f6\uff0c\u5b83\u901a\u77e5\u4e3b \u670d\u52a1\u5668\u5728\u65e5\u5fd7\u4e2d\u8bfb\u53d6\u7684\u6700\u540e\u4e00\u6b21\u6210\u529f\u66f4\u65b0\u7684\u4f4d\u7f6e\u3002\u4ece\u670d\u52a1\u5668\u63a5\u6536\u4ece\u90a3\u65f6\u8d77\u53d1\u751f \u7684\u4efb\u4f55\u66f4\u65b0\uff0c\u7136\u540e\u5c01\u9501\u5e76\u7b49\u5f85\u4e3b\u670d\u52a1\u5668\u901a\u77e5\u65b0\u7684\u66f4\u65b0\u3002 <br>\n\u8fc7\u7a0b\u5982\u4e0b \uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u4e3b\u670d\u52a1\u5668 \u628a\u66f4\u65b0\u8bb0\u5f55\u5230\u4e8c\u8fdb\u5236\u65e5\u5fd7\u6587\u4ef6\u4e2d\u3002 <\/li><li>\u4ece\u670d\u52a1\u5668\u628a\u4e3b\u670d\u52a1\u5668\u7684\u4e8c\u8fdb\u5236\u65e5\u5fd7\u62f7\u8d1d \u5230\u81ea\u5df1\u7684\u4e2d\u7ee7\u65e5\u5fd7(replay log)\u4e2d\u3002 <\/li><li>\u4ece\u670d\u52a1\u5668\u91cd\u505a\u4e2d\u7ee7\u65e5\u5fd7\u4e2d\u7684\u65f6\u95f4\uff0c \u628a\u66f4\u65b0\u5e94\u7528\u5230\u81ea\u5df1\u7684\u6570\u636e\u5e93\u4e0a\u3002<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">8\u3001mysql \u4e2d myISAM\u4e0e innodb \u7684\u533a\u522b?<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u4e8b\u52a1\u652f\u6301 &gt; MyISAM:\u5f3a\u8c03\u7684\u662f\u6027\u80fd\uff0c\u6bcf\u6b21\u67e5\u8be2\u5177\u6709\u539f\u5b50\u6027,\u5176\u6267\u884c\u6570 \u5ea6\u6bd4 InnoDB \u7c7b\u578b\u66f4\u5feb\uff0c\u4f46\u662f\u4e0d\u63d0\u4f9b\u4e8b\u52a1\u652f\u6301\u3002&gt; InnoDB:\u63d0\u4f9b\u4e8b \u52a1\u652f\u6301\u4e8b\u52a1\uff0c\u5916\u90e8\u952e\u7b49\u9ad8\u7ea7\u6570\u636e\u5e93\u529f\u80fd\u3002\u5177\u6709\u4e8b\u52a1(commit)\u3001\u56de\u6eda (rollback)\u548c\u5d29\u6e83\u4fee\u590d\u80fd\u529b(crash recovery capabilities)\u7684\u4e8b\u52a1\u5b89\u5168 (transaction-safe (ACID compliant))\u578b\u8868\u3002 <\/li><li>InnoDB \u652f\u6301\u884c\u7ea7\u9501\uff0c\u800c MyISAM \u652f\u6301\u8868\u7ea7\u9501. &gt;&gt; \u7528\u6237\u5728\u64cd\u4f5c myisam \u8868\u65f6\uff0cselect\uff0cupdate\uff0cdelete\uff0cinsert \u8bed\u53e5\u90fd\u4f1a\u7ed9\u8868\u81ea\u52a8 \u52a0\u9501\uff0c\u5982\u679c\u52a0\u9501\u4ee5\u540e\u7684\u8868\u6ee1\u8db3 insert \u5e76\u53d1\u7684\u60c5\u51b5\u4e0b\uff0c\u53ef\u4ee5\u5728\u8868\u7684\u5c3e\u90e8\u63d2 \u5165\u65b0\u7684\u6570\u636e\u3002<\/li><li>InnoDB \u652f\u6301 MVCC, \u800c MyISAM \u4e0d\u652f\u6301\u3002<\/li><li>InnoDB\u652f\u6301\u5916\u952e\uff0c\u800cMyISAM\u4e0d\u652f\u6301\u3002<\/li><li>\u8868\u4e3b\u952e\uff0cMyISAM\uff1a\u5141\u8bb8\u6ca1\u6709\u4efb\u4f55\u7d22\u5f15\u548c\u4e3b\u952e\u7684\u8868\u5b58\u5728\uff0c\u7d22\u5f15\u90fd\u662f\u4fdd\u5b58\u884c\u7684\u5730\u5740\u3002InnoDB:\u5982\u679c\u6ca1\u6709\u8bbe\u5b9a\u4e3b\u952e\u6216\u8005\u975e\u7a7a\u552f\u4e00\u7d22\u5f15\uff0c\u5c31\u4f1a \u81ea\u52a8\u751f\u6210\u4e00\u4e2a 6 \u5b57\u8282\u7684\u4e3b\u952e(\u7528\u6237\u4e0d\u53ef\u89c1)\uff0c\u6570\u636e\u662f\u4e3b\u7d22\u5f15\u7684\u4e00\u90e8\u5206\uff0c\u9644 \u52a0\u7d22\u5f15\u4fdd\u5b58\u7684\u662f\u4e3b\u7d22\u5f15\u7684\u503c\u3002 <\/li><li>InnoDB \u4e0d\u652f\u6301\u5168\u6587\u7d22\u5f15\uff0c\u800c MyISAM \u652f\u6301\u3002 <\/li><li>\u53ef\u79fb\u690d\u6027\u3001\u5907\u4efd\u53ca\u6062\u590d\uff0cMyISAM:\u6570\u636e\u662f\u4ee5\u6587\u4ef6\u7684\u5f62\u5f0f\u5b58\u50a8\uff0c\u6240\u4ee5\u5728\u8de8\u5e73\u53f0\u7684\u6570\u636e\u8f6c\u79fb\u4e2d\u4f1a\u5f88\u65b9\u4fbf\u3002\u5728\u5907\u4efd\u548c\u6062\u590d\u65f6\u53ef\u5355\u72ec\u9488\u5bf9\u67d0\u4e2a\u8868\u8fdb \u884c\u64cd\u4f5c\u3002InnoDB:\u514d\u8d39\u7684\u65b9\u6848\u53ef\u4ee5\u662f\u62f7\u8d1d\u6570\u636e\u6587\u4ef6\u3001\u5907\u4efd binlog\uff0c\u6216\u8005\u7528 mysqldump\uff0c\u5728\u6570\u636e\u91cf\u8fbe\u5230\u51e0\u5341 G \u7684\u65f6\u5019\u5c31\u76f8\u5bf9\u75db\u82e6\u4e86\u3002<\/li><li>\u5b58\u50a8\u7ed3\u6784\uff0cMyISAM:\u6bcf\u4e2a MyISAM \u5728\u78c1\u76d8\u4e0a\u5b58\u50a8\u6210\u4e09\u4e2a\u6587\u4ef6\u3002\u7b2c\u4e00 \u4e2a\u6587\u4ef6\u7684\u540d\u5b57\u4ee5\u8868\u7684\u540d\u5b57\u5f00\u59cb\uff0c\u6269\u5c55\u540d\u6307\u51fa\u6587\u4ef6\u7c7b\u578b\u3002.frm \u6587\u4ef6\u5b58\u50a8\u8868 \u5b9a\u4e49\u3002\u6570\u636e\u6587\u4ef6\u7684\u6269\u5c55\u540d\u4e3a.MYD (MYData)\u3002\u7d22\u5f15\u6587\u4ef6\u7684\u6269\u5c55\u540d \u662f.MYI (MYIndex)\u3002InnoDB:\u6240\u6709\u7684\u8868\u90fd\u4fdd\u5b58\u5728\u540c\u4e00\u4e2a\u6570\u636e\u6587\u4ef6 \u4e2d(\u4e5f\u53ef\u80fd\u662f\u591a\u4e2a\u6587\u4ef6\uff0c\u6216\u8005\u662f\u72ec\u7acb\u7684\u8868\u7a7a\u95f4\u6587\u4ef6)\uff0cInnoDB \u8868\u7684\u5927 \u5c0f\u53ea\u53d7\u9650\u4e8e\u64cd\u4f5c\u7cfb\u7edf\u6587\u4ef6\u7684\u5927\u5c0f\uff0c\u4e00\u822c\u4e3a 2GB\u3002<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">9\u3001MySQL \u4e2d InnoDB \u652f\u6301\u7684\u56db\u79cd\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\u540d\u79f0\uff0c\u4ee5\u53ca\u9010\u7ea7\u4e4b\u95f4\u7684\u533a \u522b?<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>Read Uncommitted(\u8bfb\u53d6\u672a\u63d0\u4ea4\u5185\u5bb9) &gt;&gt; \u5728\u8be5\u9694\u79bb\u7ea7\u522b\uff0c\u6240\u6709\u4e8b\u52a1\u90fd\u53ef\u4ee5\u770b\u5230\u5176\u4ed6\u672a\u63d0\u4ea4\u4e8b\u52a1\u7684\u6267\u884c\u7ed3\u679c\u3002\u672c\u9694\u79bb\u7ea7\u522b\u5f88\u5c11\u7528\u4e8e\u5b9e\u9645\u5e94\u7528\uff0c\u56e0\u4e3a\u5b83\u7684\u6027\u80fd\u4e5f\u4e0d\u6bd4\u5176\u4ed6\u7ea7\u522b\u597d\u591a\u5c11\u3002\u8bfb\u53d6\u672a\u63d0\u4ea4\u7684\u6570\u636e\uff0c\u4e5f\u88ab\u79f0\u4e4b\u4e3a\u810f\u8bfb(Dirty Read)\u3002 <\/li><li>Read Committed(\u8bfb\u53d6\u63d0\u4ea4\u5185\u5bb9) &gt;&gt; \u8fd9\u662f\u5927\u591a\u6570\u6570\u636e\u5e93\u7cfb\u7edf\u7684\u9ed8\u8ba4\u9694\u79bb\u7ea7\u522b(\u4f46\u4e0d\u662f MySQL \u9ed8\u8ba4\u7684)\u3002\u5b83\u6ee1\u8db3\u4e86\u9694\u79bb\u7684\u7b80\u5355\u5b9a\u4e49:\u4e00\u4e2a\u4e8b\u52a1\u53ea\u80fd\u770b\u89c1\u5df2\u7ecf\u63d0\u4ea4\u4e8b\u52a1\u6240\u505a\u7684\u6539\u53d8\u3002\u8fd9\u79cd\u9694\u79bb\u7ea7\u522b\u4e5f\u652f\u6301\u6240\u8c13\u7684\u4e0d\u53ef\u91cd\u590d\u8bfb(Nonrepeatable Read)\uff0c\u56e0\u4e3a\u540c\u4e00\u4e8b\u52a1\u7684\u5176\u4ed6\u5b9e\u4f8b\u5728\u8be5\u5b9e\u4f8b\u5904\u7406\u5176\u95f4\u53ef\u80fd\u4f1a\u6709\u65b0\u7684 commit\uff0c\u6240\u4ee5\u540c\u4e00 select \u53ef\u80fd\u8fd4\u56de\u4e0d\u540c\u7ed3\u679c\u3002 <\/li><li>Repeatable Read(\u53ef\u91cd\u8bfb) &gt;&gt; \u8fd9\u662f MySQL \u7684\u9ed8\u8ba4\u4e8b\u52a1\u9694\u79bb\u7ea7\u522b\uff0c\u5b83\u786e\u4fdd\u540c\u4e00\u4e8b\u52a1\u7684\u591a\u4e2a\u5b9e\u4f8b\u5728\u5e76\u53d1\u8bfb\u53d6\u6570\u636e\u65f6\uff0c\u4f1a\u770b\u5230\u540c\u6837\u7684\u6570\u636e\u884c\u3002\u4e0d\u8fc7\u7406\u8bba\u4e0a\uff0c\u8fd9\u4f1a\u5bfc\u81f4\u53e6\u4e00\u4e2a\u68d8\u624b\u7684\u95ee\u9898:\u5e7b\u8bfb(Phantom Read)\u3002\u7b80\u5355\u7684\u8bf4\uff0c\u5e7b\u8bfb\u6307\u5f53\u7528\u6237\u8bfb\u53d6\u67d0\u4e00\u8303\u56f4\u7684\u6570\u636e\u884c\u65f6\uff0c\u53e6\u4e00\u4e2a\u4e8b\u52a1\u53c8\u5728\u8be5\u8303\u56f4\u5185\u63d2\u5165\u4e86\u65b0\u884c\uff0c\u5f53\u7528\u6237\u518d\u8bfb\u53d6\u8be5\u8303\u56f4\u7684\u6570\u636e\u884c\u65f6\uff0c\u4f1a\u53d1\u73b0\u6709\u65b0\u7684\u201c\u5e7b\u5f71\u201d\u884c\u3002InnoDB \u548c Falcon \u5b58\u50a8\u5f15\u64ce\u901a\u8fc7\u591a\u7248\u672c\u5e76\u53d1\u63a7\u5236(MVCC\uff0cMultiversion Concurrency Control \u95f4\u9699\u9501)\u673a\u5236\u89e3\u51b3\u4e86\u8be5\u95ee\u9898\u3002\u6ce8:\u5176\u5b9e\u591a\u7248\u672c\u53ea\u662f\u89e3\u51b3\u4e0d\u53ef\u91cd\u590d\u8bfb\u95ee\u9898\uff0c\u800c\u52a0\u4e0a\u95f4\u9699\u9501(\u4e5f\u5c31\u662f\u5b83\u8fd9\u91cc\u6240\u8c13\u7684\u5e76\u53d1\u63a7\u5236)\u624d\u89e3\u51b3\u4e86\u5e7b\u8bfb\u95ee\u9898\u3002 <\/li><li>Serializable(\u53ef\u4e32\u884c\u5316) &gt;&gt; \u8fd9\u662f\u6700\u9ad8\u7684\u9694\u79bb\u7ea7\u522b\uff0c\u5b83\u901a\u8fc7\u5f3a\u5236\u4e8b\u52a1 \u6392\u5e8f\uff0c\u4f7f\u4e4b\u4e0d\u53ef\u80fd\u76f8\u4e92\u51b2\u7a81\uff0c\u4ece\u800c\u89e3\u51b3\u5e7b\u8bfb\u95ee\u9898\u3002\u7b80\u8a00\u4e4b\uff0c\u5b83\u662f\u5728\u6bcf\u4e2a \u8bfb\u7684\u6570\u636e\u884c\u4e0a\u52a0\u4e0a\u5171\u4eab\u9501\u3002\u5728\u8fd9\u4e2a\u7ea7\u522b\uff0c\u53ef\u80fd\u5bfc\u81f4\u5927\u91cf\u7684\u8d85\u65f6\u73b0\u8c61\u548c\u9501 \u7ade\u4e89\u3002<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">10\u3001[SELECT *] \u548c[SELECT \u5168\u90e8\u5b57\u6bb5]\u7684 2 \u79cd\u5199\u6cd5\u6709\u4f55\u4f18\u7f3a\u70b9?<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u524d\u8005\u8981\u89e3\u6790\u6570\u636e\u5b57\u5178\uff0c\u540e\u8005\u4e0d\u9700\u8981<\/li><li>\u7ed3\u679c\u8f93\u51fa\u987a\u5e8f\uff0c\u524d\u8005\u4e0e\u5efa\u8868\u5217\u987a\u5e8f\u76f8\u540c\uff0c\u540e\u8005\u6309\u6307\u5b9a\u5b57\u6bb5\u987a\u5e8f\u3002<\/li><li>\u8868\u5b57\u6bb5\u6539\u540d\uff0c\u524d\u8005\u4e0d\u9700\u8981\u4fee\u6539\uff0c\u540e\u8005\u9700\u8981\u6539<\/li><li>\u540e\u8005\u53ef\u4ee5\u5efa\u7acb\u7d22\u5f15\u8fdb\u884c\u4f18\u5316\uff0c\u524d\u8005\u65e0\u6cd5\u4f18\u5316<\/li><li>\u540e\u8005\u7684\u53ef\u8bfb\u6027\u6bd4\u524d\u8005\u8981\u9ad8<\/li><\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">11\u3001\u7b80\u8ff0 Mybatis \u7684\u63d2\u4ef6\u8fd0\u884c\u539f\u7406\uff0c\u4ee5\u53ca\u5982\u4f55\u7f16\u5199\u4e00\u4e2a\u63d2\u4ef6?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Mybatis \u4ec5\u53ef\u4ee5\u7f16\u5199\u9488\u5bf9 ParameterHandler\u3001ResultSetHandler\u3001StatementHandler\u3001 Executor \u8fd9 4 \u79cd\u63a5\u53e3\u7684\u63d2\u4ef6\uff0cMybatis \u901a\u8fc7\u52a8\u6001\u4ee3\u7406\uff0c\u4e3a\u9700\u8981\u62e6\u622a\u7684\u63a5\u53e3\u751f\u6210\u4ee3\u7406\u5bf9\u8c61\u4ee5\u5b9e \u73b0\u63a5\u53e3\u65b9\u6cd5\u62e6\u622a\u529f\u80fd\uff0c\u6bcf\u5f53\u6267\u884c\u8fd9 4 \u79cd\u63a5\u53e3\u5bf9\u8c61\u7684\u65b9\u6cd5\u65f6\uff0c\u5c31\u4f1a\u8fdb\u5165\u62e6\u622a\u65b9\u6cd5\uff0c\u5177\u4f53\u5c31\u662f InvocationHandler \u7684 invoke()\u65b9\u6cd5\uff0c\u5f53\u7136\uff0c\u53ea\u4f1a\u62e6\u622a\u90a3\u4e9b\u4f60\u6307\u5b9a\u9700\u8981\u62e6\u622a\u7684\u65b9\u6cd5\u3002 <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5b9e\u73b0 Mybatis \u7684 Interceptor \u63a5\u53e3\u5e76\u590d\u5199 intercept()\u65b9\u6cd5\uff0c\u7136\u540e\u5728\u7ed9\u63d2\u4ef6\u7f16\u5199\u6ce8\u89e3\uff0c\u6307\u5b9a \u8981\u62e6\u622a\u54ea\u4e00\u4e2a\u63a5\u53e3\u7684\u54ea\u4e9b\u65b9\u6cd5\u5373\u53ef\uff0c\u8bb0\u4f4f\uff0c\u522b\u5fd8\u4e86\u5728\u914d\u7f6e\u6587\u4ef6\u4e2d\u914d\u7f6e\u4f60\u7f16\u5199\u7684\u63d2\u4ef6\u3002 <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">12\u3001#{}\u548c${}\u7684\u533a\u522b\u662f\u4ec0\u4e48?<\/p>\n\n\n\n{}\u662f\u9884\u7f16\u8bd1\u5904\u7406\uff0c${}\u662f\u5b57\u7b26\u4e32\u66ff\u6362\u3002\n\n\n\n<p class=\"wp-block-paragraph\">Mybatis \u5728\u5904\u7406#{}\u65f6\uff0c\u4f1a\u5c06 sql \u4e2d\u7684#{}\u66ff\u6362\u4e3a?\u53f7\uff0c\u8c03\u7528 PreparedStatement \u7684 set \u65b9\u6cd5 \u6765\u8d4b\u503c\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Mybatis \u5728\u5904\u7406${}\u65f6\uff0c\u5c31\u662f\u628a${}\u66ff\u6362\u6210\u53d8\u91cf\u7684\u503c\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f7f\u7528#{}\u53ef\u4ee5\u6709\u6548\u7684\u9632\u6b62 SQL \u6ce8\u5165\uff0c\u63d0\u9ad8\u7cfb\u7edf\u5b89\u5168\u6027\u3002 <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">13\u3001\u4ec0\u4e48\u662f\u7d22\u5f15\uff1f\u8bf7\u7b80\u8ff0\u5e38\u7528\u7684\u7d22\u5f15\u6709\u54ea\u4e9b\u79cd\u7c7b?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7d22\u5f15\u662f\u5bf9\u6570\u636e\u5e93\u8868\u4e2d\u4e00\u5217\u6216\u591a\u5217\u7684\u503c\u8fdb\u884c\u6392\u5e8f\u7684\u4e00\u79cd\u7ed3\u6784\uff0c\u4f7f\u7528\u7d22\u5f15\u53ef\u5feb\u901f\u8bbf\u95ee\u6570\u636e\u5e93\u8868\u4e2d\u7684\u7279\u5b9a\u4fe1\u606f\u3002\u5982\u679c\u60f3\u6309\u7279\u5b9a\u804c\u5458\u7684\u59d3\u6765\u67e5\u627e\u4ed6\u6216\u5979\uff0c\u5219\u5728\u8868\u4e2d\u641c\u7d22\u6240\u6709\u7684\u884c\u76f8\u6bd4\uff0c\u7d22\u5f15\u6709\u52a9\u4e8e\u66f4\u5feb\u5730\u83b7\u53d6\u4fe1\u606f<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u901a\u4fd7\u7684\u8bb2\uff0c\u7d22\u5f15\u5c31\u662f\u6570\u636e\u7684\u76ee\u5f55\uff0c\u5c31\u50cf\u770b\u4e66\u4e00\u6837\uff0c\u5047\u5982\u6211\u60f3\u770b\u7b2c\u4e09\u7ae0\u7b2c\u56db\u8282\u7684\u5185\u5bb9\uff0c\u5982\u679c\u6709\u76ee\u5f55\uff0c\u6211\u76f4\u63a5\u7ffb\u76ee\u5f55\uff0c\u627e\u5230\u7b2c\u4e09\u7ae0\u7b2c\u56db\u8282\u7684\u9875\u7801\u5373\u53ef\u3002\u5982\u679c\u6ca1\u6709\u76ee\u5f55\uff0c\u6211\u5c31\u9700\u8981\u5c06\u4ece\u4e66\u7684\u5f00\u5934\u5f00\u59cb\uff0c\u4e00\u9875\u4e00\u9875\u7ffb\uff0c\u76f4\u5230\u7ffb\u5230\u7b2c\u4e09\u7ae0\u7b2c\u56db\u8282\u7684\u5185\u5bb9\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">MySQL\u7d22\u5f15\u7684\u5206\u7c7b<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6211\u4eec\u6839\u636e\u5bf9\u4ee5\u5217\u5c5e\u6027\u751f\u6210\u7684\u7d22\u5f15\u5927\u81f4\u5206\u4e3a\u4e24\u7c7b\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5355\u5217\u7d22\u5f15\uff1a\u4ee5\u8be5\u8868\u7684\u5355\u4e2a\u5217\uff0c\u751f\u6210\u7684\u7d22\u5f15\u6811\uff0c\u5c31\u79f0\u4e3a\u8be5\u8868\u7684\u5355\u5217\u7d22\u5f15<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7ec4\u5408\u7d22\u5f15\uff1a\u4ee5\u8be5\u8868\u7684\u591a\u4e2a\u5217\u7ec4\u5408\uff0c\u4e00\u8d77\u751f\u6210\u7684\u7d22\u5f15\u6811\uff0c\u5c31\u79f0\u4e3a\u8be5\u8868\u7684\u7ec4\u5408\u7d22\u5f15\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5355\u5217\u7d22\u5f15\u53c8\u6709\u5177\u4f53\u7ec6\u7684\u5212\u5206\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e3b\u952e\u7d22\u5f15\uff1a\u4ee5\u8be5\u8868\u4e3b\u952e\u751f\u6210\u7684\u7d22\u5f15\u6811\uff0c\u5c31\u79f0\u4e3a\u8be5\u8868\u7684\u4e3b\u952e\u7d22\u5f15\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u552f\u4e00\u7d22\u5f15\uff1a\u4ee5\u8be5\u8868\u552f\u4e00\u5217\u751f\u6210\u7684\u7d22\u5f15\u6811\uff0c\u5c31\u79f0\u4e3a\u8be5\u8868\u7684\u552f\u4e00\u7d22\u5f15\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u666e\u901a\u7d22\u5f15\uff1a\u4ee5\u8be5\u8868\u7684\u666e\u901a\u5217\uff08\u975e\u4e3b\u952e\uff0c\u975e\u552f\u4e00\u5217\uff09\u751f\u6210\u7684\u7d22\u5f15\u6811\uff0c\u5c31\u79f0\u4e3a\u8be5\u8868\u7684\u666e\u901a\u7d22\u5f15\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">14\u3001\u7d22\u5f15\u662f\u4e2a\u4ec0\u4e48\u6837\u7684\u6570\u636e\u7ed3\u6784\u5462?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b54\uff1a\u7d22\u5f15\u7684\u6570\u636e\u7ed3\u6784\u548c\u5177\u4f53\u5b58\u50a8\u5f15\u64ce\u7684\u5b9e\u73b0\u6709\u5173, \u5728MySQL\u4e2d\u4f7f\u7528\u8f83\u591a\u7684\u7d22\u5f15\u6709Hash\u7d22\u5f15,B+\u6811\u7d22\u5f15\u7b49\u3002\u800c\u6211\u4eec\u7ecf\u5e38\u4f7f\u7528\u7684InnoDB\u5b58\u50a8\u5f15\u64ce\u7684\u9ed8\u8ba4\u7d22\u5f15\u5b9e\u73b0\u4e3a:B+\u6811\u7d22\u5f15\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">15\u3001Hash\u7d22\u5f15\u548cB+\u6811\u6240\u6709\u6709\u4ec0\u4e48\u533a\u522b\u6216\u8005\u8bf4\u4f18\u52a3\u5462?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b54\uff1a\u9996\u5148\u8981\u77e5\u9053Hash\u7d22\u5f15\u548cB+\u6811\u7d22\u5f15\u7684\u5e95\u5c42\u5b9e\u73b0\u539f\u7406:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">hash\u7d22\u5f15\u5e95\u5c42\u5c31\u662fhash\u8868\uff0c\u8fdb\u884c\u67e5\u627e\u65f6\uff0c\u8c03\u7528\u4e00\u6b21hash\u51fd\u6570\u5c31\u53ef\u4ee5\u83b7\u53d6\u5230\u76f8\u5e94\u7684\u952e\u503c\uff0c\u4e4b\u540e\u8fdb\u884c\u56de\u8868\u67e5\u8be2\u83b7\u5f97\u5b9e\u9645\u6570\u636e\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B+\u6811\u5e95\u5c42\u5b9e\u73b0\u662f\u591a\u8def\u5e73\u8861\u67e5\u627e\u6811\uff0c\u5bf9\u4e8e\u6bcf\u4e00\u6b21\u7684\u67e5\u8be2\u90fd\u662f\u4ece\u6839\u8282\u70b9\u51fa\u53d1\uff0c\u67e5\u627e\u5230\u53f6\u5b50\u8282\u70b9\u65b9\u53ef\u4ee5\u83b7\u5f97\u6240\u67e5\u952e\u503c\uff0c\u7136\u540e\u6839\u636e\u67e5\u8be2\u5224\u65ad\u662f\u5426\u9700\u8981\u56de\u8868\u67e5\u8be2\u6570\u636e\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u90a3\u4e48\u53ef\u4ee5\u770b\u51fa\u4ed6\u4eec\u6709\u4ee5\u4e0b\u7684\u4e0d\u540c\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">hash\u7d22\u5f15\u8fdb\u884c\u7b49\u503c\u67e5\u8be2\u66f4\u5feb(\u4e00\u822c\u60c5\u51b5\u4e0b)\uff0c\u4f46\u662f\u5374\u65e0\u6cd5\u8fdb\u884c\u8303\u56f4\u67e5\u8be2\u3002\u56e0\u4e3a\u5728hash\u7d22\u5f15\u4e2d\u7ecf\u8fc7hash\u51fd\u6570\u5efa\u7acb\u7d22\u5f15\u4e4b\u540e\uff0c\u7d22\u5f15\u7684\u987a\u5e8f\u4e0e\u539f\u987a\u5e8f\u65e0\u6cd5\u4fdd\u6301\u4e00\u81f4\uff0c\u4e0d\u80fd\u652f\u6301\u8303\u56f4\u67e5\u8be2\u3002\u800cB+\u6811\u7684\u7684\u6240\u6709\u8282\u70b9\u7686\u9075\u5faa(\u5de6\u8282\u70b9\u5c0f\u4e8e\u7236\u8282\u70b9\uff0c\u53f3\u8282\u70b9\u5927\u4e8e\u7236\u8282\u70b9\uff0c\u591a\u53c9\u6811\u4e5f\u7c7b\u4f3c)\uff0c\u5929\u7136\u652f\u6301\u8303\u56f4\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">hash\u7d22\u5f15\u4e0d\u652f\u6301\u4f7f\u7528\u7d22\u5f15\u8fdb\u884c\u6392\u5e8f\uff0c\u539f\u7406\u540c\u4e0a\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">hash\u7d22\u5f15\u4e0d\u652f\u6301\u6a21\u7cca\u67e5\u8be2\u4ee5\u53ca\u591a\u5217\u7d22\u5f15\u7684\u6700\u5de6\u524d\u7f00\u5339\u914d.\u539f\u7406\u4e5f\u662f\u56e0\u4e3ahash\u51fd\u6570\u7684\u4e0d\u53ef\u9884\u6d4b\uff0cAAAA\u548cAAAAB\u7684\u7d22\u5f15\u6ca1\u6709\u76f8\u5173\u6027\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">hash\u7d22\u5f15\u4efb\u4f55\u65f6\u5019\u90fd\u907f\u514d\u4e0d\u4e86\u56de\u8868\u67e5\u8be2\u6570\u636e\uff0c\u800cB+\u6811\u5728\u7b26\u5408\u67d0\u4e9b\u6761\u4ef6(\u805a\u7c07\u7d22\u5f15\uff0c\u8986\u76d6\u7d22\u5f15\u7b49)\u7684\u65f6\u5019\u53ef\u4ee5\u53ea\u901a\u8fc7\u7d22\u5f15\u5b8c\u6210\u67e5\u8be2\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">hash\u7d22\u5f15\u867d\u7136\u5728\u7b49\u503c\u67e5\u8be2\u4e0a\u8f83\u5feb\uff0c\u4f46\u662f\u4e0d\u7a33\u5b9a\uff0c\u6027\u80fd\u4e0d\u53ef\u9884\u6d4b\u3002\u5f53\u67d0\u4e2a\u952e\u503c\u5b58\u5728\u5927\u91cf\u91cd\u590d\u7684\u65f6\u5019\uff0c\u53d1\u751fhash\u78b0\u649e\uff0c\u6b64\u65f6\u6548\u7387\u53ef\u80fd\u6781\u5dee\u3002\u800cB+\u6811\u7684\u67e5\u8be2\u6548\u7387\u6bd4\u8f83\u7a33\u5b9a\uff0c\u5bf9\u4e8e\u6240\u6709\u7684\u67e5\u8be2\u90fd\u662f\u4ece\u6839\u8282\u70b9\u5230\u53f6\u5b50\u8282\u70b9\uff0c\u4e14\u6811\u7684\u9ad8\u5ea6\u8f83\u4f4e\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u56e0\u6b64\uff0c\u5728\u5927\u591a\u6570\u60c5\u51b5\u4e0b\uff0c\u76f4\u63a5\u9009\u62e9B+\u6811\u7d22\u5f15\u53ef\u4ee5\u83b7\u5f97\u7a33\u5b9a\u4e14\u8f83\u597d\u7684\u67e5\u8be2\u901f\u5ea6\u3002\u800c\u4e0d\u9700\u8981\u4f7f\u7528hash\u7d22\u5f15\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">16\u3001\u4e0a\u9762\u63d0\u5230\u4e86B+\u6811\u5728\u6ee1\u8db3\u805a\u7c07\u7d22\u5f15\u548c\u8986\u76d6\u7d22\u5f15\u7684\u65f6\u5019\u4e0d\u9700\u8981\u56de\u8868\u67e5\u8be2\u6570\u636e,\u4ec0\u4e48\u662f\u805a\u7c07\u7d22\u5f15?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b54\uff1a\u5728B+\u6811\u7684\u7d22\u5f15\u4e2d\uff0c\u53f6\u5b50\u8282\u70b9\u53ef\u80fd\u5b58\u50a8\u4e86\u5f53\u524d\u7684key\u503c\uff0c\u4e5f\u53ef\u80fd\u5b58\u50a8\u4e86\u5f53\u524d\u7684key\u503c\u4ee5\u53ca\u6574\u884c\u7684\u6570\u636e\uff0c\u8fd9\u5c31\u662f\u805a\u7c07\u7d22\u5f15\u548c\u975e\u805a\u7c07\u7d22\u5f15.\u3002\u5728InnoDB\u4e2d\uff0c\u53ea\u6709\u4e3b\u952e\u7d22\u5f15\u662f\u805a\u7c07\u7d22\u5f15\uff0c\u5982\u679c\u6ca1\u6709\u4e3b\u952e\uff0c\u5219\u6311\u9009\u4e00\u4e2a\u552f\u4e00\u952e\u5efa\u7acb\u805a\u7c07\u7d22\u5f15\uff0c\u5982\u679c\u6ca1\u6709\u552f\u4e00\u952e\uff0c\u5219\u9690\u5f0f\u7684\u751f\u6210\u4e00\u4e2a\u952e\u6765\u5efa\u7acb\u805a\u7c07\u7d22\u5f15\u3002\u5f53\u67e5\u8be2\u4f7f\u7528\u805a\u7c07\u7d22\u5f15\u65f6\uff0c\u5728\u5bf9\u5e94\u7684\u53f6\u5b50\u8282\u70b9\uff0c\u53ef\u4ee5\u83b7\u53d6\u5230\u6574\u884c\u6570\u636e,\u56e0\u6b64\u4e0d\u7528\u518d\u6b21\u8fdb\u884c\u56de\u8868\u67e5\u8be2\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">17\u3001\u975e\u805a\u7c07\u7d22\u5f15\u4e00\u5b9a\u4f1a\u56de\u8868\u67e5\u8be2\u5417?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b54\uff1a\u4e0d\u4e00\u5b9a\u3002\u8fd9\u6d89\u53ca\u5230\u67e5\u8be2\u8bed\u53e5\u6240\u8981\u6c42\u7684\u5b57\u6bb5\u662f\u5426\u5168\u90e8\u547d\u4e2d\u4e86\u7d22\u5f15\uff0c\u5982\u679c\u5168\u90e8\u547d\u4e2d\u4e86\u7d22\u5f15\uff0c\u90a3\u4e48\u5c31\u4e0d\u5fc5\u518d\u8fdb\u884c\u56de\u8868\u67e5\u8be2\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e3e\u4e2a\u7b80\u5355\u7684\u4f8b\u5b50\uff0c\u5047\u8bbe\u6211\u4eec\u5728\u5458\u5de5\u8868\u7684\u5e74\u9f84\u4e0a\u5efa\u7acb\u4e86\u7d22\u5f15\uff0c\u90a3\u4e48\u5f53\u8fdb\u884cselect age from employee where age &lt; 20\u7684\u67e5\u8be2\u65f6\uff0c\u5728\u7d22\u5f15\u7684\u53f6\u5b50\u8282\u70b9\u4e0a\uff0c\u5df2\u7ecf\u5305\u542b\u4e86age\u4fe1\u606f\uff0c\u4e0d\u4f1a\u518d\u6b21\u8fdb\u884c\u56de\u8868\u67e5\u8be2\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">18\u3001\u5bf9MySQL\u7684\u9501\u4e86\u89e3\u5417?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b54\uff1a\u5f53\u6570\u636e\u5e93\u6709\u5e76\u53d1\u4e8b\u52a1\u7684\u65f6\u5019\uff0c\u53ef\u80fd\u4f1a\u4ea7\u751f\u6570\u636e\u7684\u4e0d\u4e00\u81f4\uff0c\u8fd9\u65f6\u5019\u9700\u8981\u4e00\u4e9b\u673a\u5236\u6765\u4fdd\u8bc1\u8bbf\u95ee\u7684\u6b21\u5e8f\uff0c\u9501\u673a\u5236\u5c31\u662f\u8fd9\u6837\u7684\u4e00\u4e2a\u673a\u5236\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5c31\u50cf\u9152\u5e97\u7684\u623f\u95f4\uff0c\u5982\u679c\u5927\u5bb6\u968f\u610f\u8fdb\u51fa\uff0c\u5c31\u4f1a\u51fa\u73b0\u591a\u4eba\u62a2\u593a\u540c\u4e00\u4e2a\u623f\u95f4\u7684\u60c5\u51b5\uff0c\u800c\u5728\u623f\u95f4\u4e0a\u88c5\u4e0a\u9501\uff0c\u7533\u8bf7\u5230\u94a5\u5319\u7684\u4eba\u624d\u53ef\u4ee5\u5165\u4f4f\u5e76\u4e14\u5c06\u623f\u95f4\u9501\u8d77\u6765\uff0c\u5176\u4ed6\u4eba\u53ea\u6709\u7b49\u4ed6\u4f7f\u7528\u5b8c\u6bd5\u624d\u53ef\u4ee5\u518d\u6b21\u4f7f\u7528\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">19\u3001MySQL\u90fd\u6709\u54ea\u4e9b\u9501\u5462?\u50cf\u4e0a\u9762\u7684\u4f8b\u5b50\u8fdb\u884c\u9501\u5b9a\u5c82\u4e0d\u662f\u6709\u70b9\u963b\u788d\u5e76\u53d1\u6548\u7387\u4e86?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b54\uff1a\u4ece\u9501\u7684\u7c7b\u522b\u4e0a\u6765\u8bb2\uff0c\u6709\u5171\u4eab\u9501\u548c\u6392\u4ed6\u9501\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5171\u4eab\u9501\uff1a\u53c8\u53eb\u505a\u8bfb\u9501\uff0c\u5f53\u7528\u6237\u8981\u8fdb\u884c\u6570\u636e\u7684\u8bfb\u53d6\u65f6\uff0c\u5bf9\u6570\u636e\u52a0\u4e0a\u5171\u4eab\u9501\uff0c\u5171\u4eab\u9501\u53ef\u4ee5\u540c\u65f6\u52a0\u4e0a\u591a\u4e2a\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6392\u4ed6\u9501\uff1a\u53c8\u53eb\u505a\u5199\u9501\uff0c\u5f53\u7528\u6237\u8981\u8fdb\u884c\u6570\u636e\u7684\u5199\u5165\u65f6\uff0c\u5bf9\u6570\u636e\u52a0\u4e0a\u6392\u4ed6\u9501\uff0c\u6392\u4ed6\u9501\u53ea\u53ef\u4ee5\u52a0\u4e00\u4e2a\uff0c\u4ed6\u548c\u5176\u4ed6\u7684\u6392\u4ed6\u9501\uff0c\u5171\u4eab\u9501\u90fd\u76f8\u65a5\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7528\u4e0a\u9762\u7684\u4f8b\u5b50\u6765\u8bf4\u5c31\u662f\u7528\u6237\u7684\u884c\u4e3a\u6709\u4e24\u79cd\uff0c\u4e00\u79cd\u662f\u6765\u770b\u623f\uff0c\u591a\u4e2a\u7528\u6237\u4e00\u8d77\u770b\u623f\u662f\u53ef\u4ee5\u63a5\u53d7\u7684\u3002\u4e00\u79cd\u662f\u771f\u6b63\u7684\u5165\u4f4f\u4e00\u665a\uff0c\u5728\u8fd9\u671f\u95f4\uff0c\u65e0\u8bba\u662f\u60f3\u5165\u4f4f\u7684\u8fd8\u662f\u60f3\u770b\u623f\u7684\u90fd\u4e0d\u53ef\u4ee5\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u9501\u7684\u7c92\u5ea6\u53d6\u51b3\u4e8e\u5177\u4f53\u7684\u5b58\u50a8\u5f15\u64ce\uff0cInnoDB\u5b9e\u73b0\u4e86\u884c\u7ea7\u9501\uff0c\u9875\u7ea7\u9501\uff0c\u8868\u7ea7\u9501\u3002\u4ed6\u4eec\u7684\u52a0\u9501\u5f00\u9500\u4ece\u5927\u5927\u5c0f\uff0c\u5e76\u53d1\u80fd\u529b\u4e5f\u662f\u4ece\u5927\u5230\u5c0f\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">20\u3001MySQL\u7684binlog\u6709\u6709\u51e0\u79cd\u5f55\u5165\u683c\u5f0f?\u5206\u522b\u6709\u4ec0\u4e48\u533a\u522b?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7b54\uff1a\u6709\u4e09\u79cd\u683c\u5f0f,statement,row\u548cmixed\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">statement\u6a21\u5f0f\u4e0b\uff0c\u8bb0\u5f55\u5355\u5143\u4e3a\u8bed\u53e5\u3002\u5373\u6bcf\u4e00\u4e2asql\u9020\u6210\u7684\u5f71\u54cd\u4f1a\u8bb0\u5f55\uff0c\u7531\u4e8esql\u7684\u6267\u884c\u662f\u6709\u4e0a\u4e0b\u6587\u7684\uff0c\u56e0\u6b64\u5728\u4fdd\u5b58\u7684\u65f6\u5019\u9700\u8981\u4fdd\u5b58\u76f8\u5173\u7684\u4fe1\u606f\uff0c\u540c\u65f6\u8fd8\u6709\u4e00\u4e9b\u4f7f\u7528\u4e86\u51fd\u6570\u4e4b\u7c7b\u7684\u8bed\u53e5\u65e0\u6cd5\u88ab\u8bb0\u5f55\u590d\u5236\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">row\u7ea7\u522b\u4e0b\uff0c\u8bb0\u5f55\u5355\u5143\u4e3a\u6bcf\u4e00\u884c\u7684\u6539\u52a8\uff0c\u57fa\u672c\u662f\u53ef\u4ee5\u5168\u90e8\u8bb0\u4e0b\u6765\u4f46\u662f\u7531\u4e8e\u5f88\u591a\u64cd\u4f5c\uff0c\u4f1a\u5bfc\u81f4\u5927\u91cf\u884c\u7684\u6539\u52a8(\u6bd4\u5982alter table)\uff0c\u56e0\u6b64\u8fd9\u79cd\u6a21\u5f0f\u7684\u6587\u4ef6\u4fdd\u5b58\u7684\u4fe1\u606f\u592a\u591a\uff0c\u65e5\u5fd7\u91cf\u592a\u5927\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">mixed\uff0c\u4e00\u79cd\u6298\u4e2d\u7684\u65b9\u6848\uff0c\u666e\u901a\u64cd\u4f5c\u4f7f\u7528statement\u8bb0\u5f55\uff0c\u5f53\u65e0\u6cd5\u4f7f\u7528statement\u7684\u65f6\u5019\u4f7f\u7528row\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6b64\u5916\uff0c\u65b0\u7248\u7684MySQL\u4e2d\u5bf9row\u7ea7\u522b\u4e5f\u505a\u4e86\u4e00\u4e9b\u4f18\u5316\uff0c\u5f53\u8868\u7ed3\u6784\u53d1\u751f\u53d8\u5316\u7684\u65f6\u5019\uff0c\u4f1a\u8bb0\u5f55\u8bed\u53e5\u800c\u4e0d\u662f\u9010\u884c\u8bb0\u5f55\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">21\u3001\u4e00\u6761sql\u6267\u884c\u8fc7\u957f\u7684\u65f6\u95f4\uff0c\u4f60\u5982\u4f55\u4f18\u5316\uff0c\u4ece\u54ea\u4e9b\u65b9\u9762\uff1f<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">1\u3001\u67e5\u770bsql\u662f\u5426\u6d89\u53ca\u591a\u8868\u7684\u8054\u8868\u6216\u8005\u5b50\u67e5\u8be2\uff0c\u5982\u679c\u6709\uff0c\u770b\u662f\u5426\u80fd\u8fdb\u884c\u4e1a\u52a1\u62c6\u5206\uff0c\u76f8\u5173\u5b57\u6bb5\u5197\u4f59\u6216\u8005\u5408\u5e76\u6210\u4e34\u65f6\u8868\uff08\u4e1a\u52a1\u548c\u7b97\u6cd5\u7684\u4f18\u5316\uff09\u3002<br>\n2\u3001\u6d89\u53ca\u94fe\u8868\u7684\u67e5\u8be2\uff0c\u662f\u5426\u80fd\u8fdb\u884c\u5206\u8868\u67e5\u8be2\uff0c\u5355\u8868\u67e5\u8be2\u4e4b\u540e\u7684\u7ed3\u679c\u8fdb\u884c\u5b57\u6bb5\u6574\u5408\u3002<br>\n3\u3001\u5982\u679c\u4ee5\u4e0a\u4e24\u79cd\u90fd\u4e0d\u80fd\u64cd\u4f5c\uff0c\u975e\u8981\u94fe\u8868\u67e5\u8be2\uff0c\u90a3\u4e48\u8003\u8651\u5bf9\u76f8\u5bf9\u5e94\u7684\u67e5\u8be2\u6761\u4ef6\u505a\u7d22\u5f15\u3002\u52a0\u5feb\u67e5\u8be2\u901f\u5ea6\u3002<br>\n4\u3001\u9488\u5bf9\u6570\u91cf\u5927\u7684\u8868\u8fdb\u884c\u5386\u53f2\u8868\u5206\u79bb\uff08\u5982\u4ea4\u6613\u6d41\u6c34\u8868\uff09\u3002<br>\n5\u3001\u6570\u636e\u5e93\u4e3b\u4ece\u5206\u79bb\uff0c\u8bfb\u5199\u5206\u79bb\uff0c\u964d\u4f4e\u8bfb\u5199\u9488\u5bf9\u540c\u4e00\u8868\u540c\u65f6\u7684\u538b\u529b\uff0c\u81f3\u4e8e\u4e3b\u4ece\u540c\u6b65\uff0cmysql\u6709\u81ea\u5e26\u7684binlog\u5b9e\u73b0 \u4e3b\u4ece\u540c\u6b65\u3002<br>\n6\u3001explain\u5206\u6790sql\u8bed\u53e5\uff0c\u67e5\u770b\u6267\u884c\u8ba1\u5212\uff0c\u5206\u6790\u7d22\u5f15\u662f\u5426\u7528\u4e0a\uff0c\u5206\u6790\u626b\u63cf\u884c\u6570\u7b49\u7b49\u3002<br>\n7\u3001\u67e5\u770bmysql\u6267\u884c\u65e5\u5fd7\uff0c\u770b\u770b\u662f\u5426\u6709\u5176\u4ed6\u65b9\u9762\u7684\u95ee\u9898\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u66f4\u591a\u9762\u8bd5\u9898\uff0c\u8bf7\u5173\u6ce8\u6211\u7684\u5fae\u4fe1\u516c\u4f17\u53f7\uff0c\u5728\u516c\u4f17\u53f7\u91cc\u641c\u7d22\u67e5\u627e\u3002<\/p>\n<!-- <audio autoplay=\"autoplay\" height=\"100\" width=\"100\" hidden=\"true\"><source src=\"https:\/\/c.coka.la\/orAvPR.mp3\" type=\"audio\/mp3\"\/><\/audio><img decoding=\"async\" src=\"https:\/\/images.weserv.nl\/?url=https:\/\/ws3.sinaimg.cn\/large\/8fa5dcfcgy1g4em3rzar5j20ib089ae0.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/> --><p><!-- <img decoding=\"async\" src=\"https:\/\/raw.githubusercontent.com\/xmt1139057136\/xttblog\/master\/8fa5dcfcgy1g4em3rzar5j20ib089ae0.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/>--><img decoding=\"async\" src=\"https:\/\/saas.51autoparts.cn\/api\/admin\/sys-file\/oss\/file?fileName=84db51f8561e448f9a4fda2eff0811f9.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/><\/p><p>\u6700\u540e\uff0c\u6b22\u8fce\u5173\u6ce8\u6211\u7684\u4e2a\u4eba\u5fae\u4fe1\u516c\u4f17\u53f7\uff1a\u4e1a\u4f59\u8349\uff08yyucao\uff09\uff01<b>\u53ef\u52a0\u4f5c\u8005\u5fae\u4fe1\u53f7\uff1a<font color=\"red\">xttblog2<\/font>\u3002\u5907\u6ce8\uff1a\u201c1\u201d\uff0c\u6dfb\u52a0\u535a\u4e3b\u5fae\u4fe1\u62c9\u4f60\u8fdb\u5fae\u4fe1\u7fa4\u3002\u5907\u6ce8\u9519\u8bef\u4e0d\u4f1a\u540c\u610f\u597d\u53cb\u7533\u8bf7\u3002<\/b>\u518d\u6b21\u611f\u8c22\u60a8\u7684\u5173\u6ce8\uff01\u540e\u7eed\u6709\u7cbe\u5f69\u5185\u5bb9\u4f1a\u7b2c\u4e00\u65f6\u95f4\u53d1\u7ed9\u60a8\uff01\u539f\u521b\u6587\u7ae0\u6295\u7a3f\u8bf7\u53d1\u9001\u81f3532009913@qq.com\u90ae\u7bb1\u3002\u5546\u52a1\u5408\u4f5c\u4e5f\u53ef\u6dfb\u52a0\u4f5c\u8005\u5fae\u4fe1\u8fdb\u884c\u8054\u7cfb\uff01<\/p><p>\u672c\u6587\u539f\u6587\u51fa\u5904\uff1a<a href=\"https:\/\/www.xttblog.com\">\u4e1a\u4f59\u8349<\/a>\uff1a &raquo; <a href=\"https:\/\/www.xttblog.com\/?p=4730\">MySQL \u6700\u65b0\u9ad8\u9891\u9762\u8bd5\u9898<\/a><\/p><!-- <div class=\"bd-reward-stl\"><button id=\"bdRewardBtn\"><span><\/span><\/button><\/div> -->","protected":false},"excerpt":{"rendered":"<p>\u53c8\u5230\u4e86\u4e00\u5e74\u7684\u9762\u8bd5\u5b63\uff0c\u4eca\u5e74\u60c5\u51b5\u7279\u6b8a\uff0c\u5f88\u591a\u4eba\u53ef\u80fd\u90fd\u7a9d\u5728\u5bb6\u91cc\uff0c\u4e5f\u6709\u4e00\u4e9b\u4eba\u51c6\u5907\u627e\u5de5\u4f5c\uff0c\u4f46\u662f\u75ab\u60c5\u4e25\u91cd\uff0c\u4e5f\u6ca1\u4f01\u4e1a\u53d1\u62db\u8058\u4fe1\u606f [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[12],"tags":[83,580,392,391,393],"class_list":["post-4730","post","type-post","status-publish","format-standard","hentry","category-sql","tag-mysql","tag-mysql----dba"],"_links":{"self":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/4730","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4730"}],"version-history":[{"count":1,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/4730\/revisions"}],"predecessor-version":[{"id":4731,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/4730\/revisions\/4731"}],"wp:attachment":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4730"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4730"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4730"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}