\u4ece\u9501\u7684\u7c7b\u522b\u4e0a\u6765\u8bb2\uff0c\u6709\u5171\u4eab\u9501\u548c\u6392\u4ed6\u9501\u3002
\n\u5171\u4eab\u9501\uff1a\u53c8\u53eb\u505a\u8bfb\u9501\u3002\u5f53\u7528\u6237\u8981\u8fdb\u884c\u6570\u636e\u7684\u8bfb\u53d6\u65f6\uff0c\u5bf9\u6570\u636e\u52a0\u4e0a\u5171\u4eab\u9501\u3002\u5171\u4eab\u9501\u53ef\u4ee5\u540c\u65f6\u52a0\u4e0a\u591a\u4e2a\u3002
\n\u6392\u4ed6\u9501\uff1a\u53c8\u53eb\u505a\u5199\u9501\u3002\u5f53\u7528\u6237\u8981\u8fdb\u884c\u6570\u636e\u7684\u5199\u5165\u65f6\uff0c\u5bf9\u6570\u636e\u52a0\u4e0a\u6392\u4ed6\u9501\u3002\u6392\u4ed6\u9501\u53ea\u53ef\u4ee5\u52a0\u4e00\u4e2a,\u4ed6\u548c\u5176\u4ed6\u7684\u6392\u4ed6\u9501\uff0c\u5171\u4eab\u9501\u90fd\u76f8\u65a5\u3002
\nMySQL \u4e2d CHAR \u548c VARCHAR \u7684\u533a\u522b\uff1f
\n1\u3001\tCHAR\u548cVARCHAR\u7c7b\u578b\u5728\u5b58\u50a8\u548c\u68c0\u7d22\u65b9\u9762\u6709\u6240\u4e0d\u540c
\n2,CHAR\u5217\u957f\u5ea6\u56fa\u5b9a\u4e3a\u521b\u5efa\u8868\u65f6\u58f0\u660e\u7684\u957f\u5ea6\uff0c\u957f\u5ea6\u503c\u8303\u56f4\u662f1\u5230255
\n\u5f53CHAR\u503c\u88ab\u5b58\u50a8\u65f6\uff0c\u5b83\u4eec\u88ab\u7528\u7a7a\u683c\u586b\u5145\u5230\u7279\u5b9a\u957f\u5ea6\uff0c\u68c0\u7d22CHAR\u503c\u65f6\u9700\u5220\u9664\u5c3e\u968f\u7a7a\u683c\u3002
\nMySQL\u5728MySQL\u6570\u636e\u5e93\u4e2dMyISAM\u548cInnoDB\u7684\u533a\u522b\uff1f
\nMyISAM\uff1a
\n\u4e0d\u652f\u6301\u4e8b\u52a1\uff0c\u4f46\u662f\u6bcf\u6b21\u67e5\u8be2\u90fd\u662f\u539f\u5b50\u7684\uff1b
\n\u652f\u6301\u8868\u7ea7\u9501\uff0c\u5373\u6bcf\u6b21\u64cd\u4f5c\u662f\u5bf9\u6574\u4e2a\u8868\u52a0\u9501\uff1b
\n\u5b58\u50a8\u8868\u7684\u603b\u884c\u6570\uff1b
\n\u4e00\u4e2aMYISAM\u8868\u6709\u4e09\u4e2a\u6587\u4ef6\uff1a\u7d22\u5f15\u6587\u4ef6\u3001\u8868\u7ed3\u6784\u6587\u4ef6\u3001\u6570\u636e\u6587\u4ef6\uff1b
\n\u91c7\u7528\u975e\u805a\u96c6\u7d22\u5f15\uff0c\u7d22\u5f15\u6587\u4ef6\u7684\u6570\u636e\u57df\u5b58\u50a8\u6307\u5411\u6570\u636e\u6587\u4ef6\u7684\u6307\u9488\u3002\u8f85\u7d22\u5f15\u4e0e\u4e3b\u7d22\u5f15\u57fa\u672c\u4e00\u81f4\uff0c\u4f46\u662f\u8f85\u7d22\u5f15\u4e0d\u7528\u4fdd\u8bc1\u552f\u4e00\u6027\u3002
\nInnoDb\uff1a
\n\u652f\u6301ACID\u7684\u4e8b\u52a1\uff0c\u652f\u6301\u4e8b\u52a1\u7684\u56db\u79cd\u9694\u79bb\u7ea7\u522b\uff1b
\n\u652f\u6301\u884c\u7ea7\u9501\u53ca\u5916\u952e\u7ea6\u675f\uff1b\u56e0\u6b64\u53ef\u4ee5\u652f\u6301\u5199\u5e76\u53d1\uff1b
\n\u4e0d\u5b58\u50a8\u603b\u884c\u6570\uff1a
\n\u4e00\u4e2aInnoDb\u5f15\u64ce\u5b58\u50a8\u5728\u4e00\u4e2a\u6587\u4ef6\u7a7a\u95f4\uff08\u5171\u4eab\u8868\u7a7a\u95f4\uff0c\u8868\u5927\u5c0f\u4e0d\u53d7\u64cd\u4f5c\u7cfb\u7edf\u63a7\u5236\uff0c\u4e00\u4e2a\u8868\u53ef\u80fd\u5206\u5e03\u5728\u591a\u4e2a\u6587\u4ef6\u91cc\uff09\uff0c\u4e5f\u6709\u53ef\u80fd\u4e3a\u591a\u4e2a\uff08\u8bbe\u7f6e\u4e3a\u72ec\u7acb\u8868\u7a7a\uff0c\u8868\u5927\u5c0f\u53d7\u64cd\u4f5c\u7cfb\u7edf\u6587\u4ef6\u5927\u5c0f\u9650\u5236\uff0c\u4e00\u822c\u4e3a2G\uff09,\u53d7\u64cd\u4f5c\u7cfb\u7edf\u6587\u4ef6\u5927\u5c0f\u7684\u9650\u5236\uff1b
\n\u4e3b\u952e\u7d22\u5f15\u91c7\u7528\u805a\u96c6\u7d22\u5f15\uff08\u7d22\u5f15\u7684\u6570\u636e\u57df\u5b58\u50a8\u6570\u636e\u6587\u4ef6\u672c\u8eab\uff09\uff0c\u8f85\u7d22\u5f15\u7684\u6570\u636e\u57df\u5b58\u50a8\u4e3b\u952e\u7684\u503c\uff1b\u56e0\u6b64\u4ece\u8f85\u7d22\u5f15\u67e5\u627e\u6570\u636e\uff0c\u9700\u8981\u5148\u901a\u8fc7\u8f85\u7d22\u5f15\u627e\u5230\u4e3b\u952e\u503c\uff0c\u518d\u8bbf\u95ee\u8f85\u7d22\u5f15\uff1b\u6700\u597d\u4f7f\u7528\u81ea\u589e\u4e3b\u952e\uff0c\u9632\u6b62\u63d2\u5165\u6570\u636e\u65f6\uff0c\u4e3a\u7ef4\u6301B+\u6811\u7ed3\u6784\uff0c\u6587\u4ef6\u7684\u5927\u8c03\u6574\u3002
\nMySQL \u4e2d select for update \u542b\u4e49\uff1f
\nselect\u67e5\u8be2\u8bed\u53e5\u662f\u4e0d\u4f1a\u52a0\u9501\u7684\uff0c\u4f46\u662fselect for update\u9664\u4e86\u6709\u67e5\u8be2\u7684\u4f5c\u7528\u5916\uff0c\u8fd8\u4f1a\u52a0\u9501\u5462,\u800c\u4e14\u5b83\u662f\u60b2\u89c2\u9501\u54e6\u3002\u81f3\u4e8e\u52a0\u4e86\u662f\u884c\u9501\u8fd8\u662f\u8868\u9501\uff0c\u8fd9\u5c31\u8981\u770b\u662f\u4e0d\u662f\u7528\u4e86\u7d22\u5f15\/\u4e3b\u952e\u5566\u3002
\n\u6ca1\u7528\u7d22\u5f15\/\u4e3b\u952e\u7684\u8bdd\u5c31\u662f\u8868\u9501\uff0c\u5426\u5219\u5c31\u662f\u884c\u9501\u3002
\n1\u3001\t\u539f\u5b50\u6027\uff1a\u4e8b\u52a1\u4f5c\u4e3a\u4e00\u4e2a\u6574\u4f53\u88ab\u6267\u884c\uff0c\u5305\u542b\u5728\u5176\u4e2d\u7684\u5bf9\u6570\u636e\u5e93\u7684\u64cd\u4f5c\u8981\u4e48\u5168\u90e8\u88ab\u6267\u884c\uff0c\u8981\u4e48\u90fd\u4e0d\u6267\u884c\u3002
\n2\u3001\t\u4e00\u81f4\u6027\uff1a\u6307\u5728\u4e8b\u52a1\u5f00\u59cb\u4e4b\u524d\u548c\u4e8b\u52a1\u7ed3\u675f\u4ee5\u540e\uff0c\u6570\u636e\u4e0d\u4f1a\u88ab\u7834\u574f\uff0c\u5047\u5982A\u8d26\u6237\u7ed9B\u8d26\u6237\u8f6c10\u5757\u94b1\uff0c\u4e0d\u7ba1\u6210\u529f\u4e0e\u5426\uff0cA\u548cB\u7684\u603b\u91d1\u989d\u662f\u4e0d\u53d8\u7684\u3002
\n3\u3001\t\u9694\u79bb\u6027\uff1a\u591a\u4e2a\u4e8b\u52a1\u5e76\u53d1\u8bbf\u95ee\u65f6\uff0c\u4e8b\u52a1\u4e4b\u95f4\u662f\u76f8\u4e92\u9694\u79bb\u7684\uff0c\u5373\u4e00\u4e2a\u4e8b\u52a1\u4e0d\u5f71\u54cd\u5176\u5b83\u4e8b\u52a1\u8fd0\u884c\u6548\u679c\u3002\u7b80\u8a00\u4e4b\uff0c\u5c31\u662f\u4e8b\u52a1\u4e4b\u95f4\u662f\u8fdb\u6c34\u4e0d\u72af\u6cb3\u6c34\u7684\u3002
\n4\u3001\t\u6301\u4e45\u6027\uff1a\u8868\u793a\u4e8b\u52a1\u5b8c\u6210\u4ee5\u540e\uff0c\u8be5\u4e8b\u52a1\u5bf9\u6570\u636e\u5e93\u6240\u4f5c\u7684\u64cd\u4f5c\u66f4\u6539\uff0c\u5c06\u6301\u4e45\u5730\u4fdd\u5b58\u5728\u6570\u636e\u5e93\u4e4b\u4e2d\u3002
\n\u4e8b\u52a1ACID\u7279\u6027\u7684\u5b9e\u73b0\u601d\u60f3
\n\u539f\u5b50\u6027\uff1a\u662f\u4f7f\u7528undo log\u6765\u5b9e\u73b0\u7684\uff0c\u5982\u679c\u4e8b\u52a1\u6267\u884c\u8fc7\u7a0b\u4e2d\u51fa\u9519\u6216\u8005\u7528\u6237\u6267\u884c\u4e86 rollback,\u7cfb\u7edf\u901a\u8fc7undo log\u65e5\u5fd7\u8fd4\u56de\u4e8b\u52a1\u5f00\u59cb\u7684\u72b6\u6001\u3002
\n\u6301\u4e45\u6027\uff1a\u4f7f\u7528redo log\u6765\u5b9e\u73b0\uff0c\u53ea\u8981redo log\u65e5\u5fd7\u6301\u4e45\u5316\u4e86\uff0c\u5f53\u7cfb\u7edf\u5d29\u6e83\uff0c\u5373\u53ef\u901a\u8fc7redo log \u628a\u6570\u636e\u6062\u590d\u3002
\n\u9694\u79bb\u6027\uff1a\u901a\u8fc7\u9501\u4ee5\u53caMVCC,\u4f7f\u4e8b\u52a1\u76f8\u4e92\u9694\u79bb\u5f00\u3002
\n\u4e00\u81f4\u6027\uff1a\u901a\u8fc7\u56de\u6eda\u3001\u6062\u590d\uff0c\u4ee5\u53ca\u5e76\u53d1\u60c5\u51b5\u4e0b\u7684\u9694\u79bb\u6027\uff0c\u4ece\u800c\u5b9e\u73b0\u4e00\u81f4\u6027\u3002
\nMySQL\u4e2d\u5982\u4f55\u4f18\u5316\u67e5\u8be2\u8fc7\u7a0b\u4e2d\u7684\u6570\u636e\u8bbf\u95ee\uff1f
\n1\u3001\t\u8bbf\u95ee\u6570\u636e\u592a\u591a\u5bfc\u81f4\u67e5\u8be2\u6027\u80fd\u4e0b\u964d
\n2\u3001\t\u786e\u5b9a\u5e94\u7528\u7a0b\u5e8f\u662f\u5426\u5728\u68c0\u7d22\u5927\u91cf\u8d85\u8fc7\u9700\u8981\u7684\u6570\u636e\uff0c\u53ef\u80fd\u662f\u592a\u591a\u884c\u6216\u5217
\n3\u3001\t\u786e\u8ba4MySQL\u670d\u52a1\u5668\u662f\u5426\u5728\u5206\u6790\u5927\u91cf\u4e0d\u5fc5\u8981\u7684\u6570\u636e\u884c
\n4\u3001\t\u907f\u514d\u72af\u5982\u4e0bSQL\u8bed\u53e5\u9519\u8bef
\n5\u3001\t\u907f\u514d\u67e5\u8be2\u4e0d\u9700\u8981\u7684\u6570\u636e\u3002\u89e3\u51b3\u529e\u6cd5\uff1a\u4f7f\u7528limit\u89e3\u51b3
\n6\u3001\t\u591a\u8868\u5173\u8054\u8fd4\u56de\u5168\u90e8\u5217\u3002\u89e3\u51b3\u529e\u6cd5\uff1a\u6307\u5b9a\u5217\u540d
\n7\u3001\t\u603b\u662f\u8fd4\u56de\u5168\u90e8\u5217\u3002\u89e3\u51b3\u529e\u6cd5\uff1a\u907f\u514d\u4f7f\u7528SELECT *
\n8\u3001\t\u91cd\u590d\u67e5\u8be2\u76f8\u540c\u7684\u6570\u636e\u3002\u89e3\u51b3\u529e\u6cd5\uff1a\u53ef\u4ee5\u7f13\u5b58\u6570\u636e\uff0c\u4e0b\u6b21\u76f4\u63a5\u8bfb\u53d6\u7f13\u5b58
\n9\u3001\t\u4f7f\u7528explain\u8fdb\u884c\u5206\u6790\uff0c\u5982\u679c\u53d1\u73b0\u67e5\u8be2\u9700\u8981\u626b\u63cf\u5927\u91cf\u7684\u6570\u636e\uff0c\u4f46\u53ea\u8fd4\u56de\u5c11\u6570\u7684\u884c\uff0c\u53ef\u4ee5\u901a\u8fc7\u5982\u4e0b\u6280\u5de7\u53bb\u4f18\u5316\uff1b
\n10\u3001\t\u4f7f\u7528\u7d22\u5f15\u8986\u76d6\u626b\u63cf\uff0c\u628a\u6240\u6709\u7684\u5217\u90fd\u653e\u5230\u7d22\u5f15\u4e2d\uff0c\u8fd9\u6837\u5b58\u50a8\u5f15\u64ce\u4e0d\u9700\u8981\u56de\u8868\u83b7\u53d6\u5bf9\u5e94\u884c\u5c31\u53ef\u4ee5\u8fd4\u56de\u7ed3\u679c\u3002
\n11\u3001\t\u6539\u53d8\u6570\u636e\u5e93\u548c\u8868\u7684\u7ed3\u6784\uff0c\u4fee\u6539\u6570\u636e\u8868\u8303\u5f0f
\n12\u3001\t\u91cd\u5199SQL\u8bed\u53e5\uff0c\u8ba9\u4f18\u5316\u5668\u53ef\u4ee5\u4ee5\u66f4\u4f18\u7684\u65b9\u5f0f\u6267\u884c\u67e5\u8be2\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u4ece\u9501\u7684\u7c7b\u522b\u4e0a\u6765\u8bb2\uff0c\u6709\u5171\u4eab\u9501\u548c\u6392\u4ed6\u9501\u3002 \u5171\u4eab\u9501\uff1a\u53c8\u53eb\u505a\u8bfb\u9501\u3002\u5f53\u7528\u6237\u8981\u8fdb\u884c\u6570\u636e\u7684\u8bfb\u53d6\u65f6\uff0c\u5bf9\u6570\u636e\u52a0\u4e0a\u5171\u4eab\u9501\u3002\u5171\u4eab\u9501\u53ef […]<\/p>\n","protected":false},"author":7,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[102],"tags":[],"class_list":["post-7844","post","type-post","status-publish","format-standard","hentry","category-db"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/7844","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/comments?post=7844"}],"version-history":[{"count":1,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/7844\/revisions"}],"predecessor-version":[{"id":7845,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/7844\/revisions\/7845"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=7844"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=7844"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=7844"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}