{"id":199765,"date":"2025-05-06T10:43:32","date_gmt":"2025-05-06T02:43:32","guid":{"rendered":"https:\/\/server.hk\/cnblog\/199765\/"},"modified":"2025-05-06T10:43:32","modified_gmt":"2025-05-06T02:43:32","slug":"mysql%e6%9f%a5%e8%af%a2%e6%8a%80%e5%b7%a7%ef%bc%9a%e7%b2%be%e7%a1%ae%e8%bf%87%e6%bb%a4%e6%95%b0%e6%8d%ae%e7%9a%84%e5%85%a8%e9%9d%a2%e6%8c%87%e5%8d%97","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/199765\/","title":{"rendered":"MySQL\u67e5\u8be2\u6280\u5de7\uff1a\u7cbe\u786e\u8fc7\u6ee4\u6570\u636e\u7684\u5168\u9762\u6307\u5357"},"content":{"rendered":"

<\/b> <\/p>\n

MySQL\u67e5\u8be2\u6280\u5de7\uff1a\u7cbe\u786e\u8fc7\u6ee4\u6570\u636e\u7684\u5168\u9762\u6307\u5357<\/h1>\n

\u4ece\u73b0\u5728\u5f00\u59cb\uff0c\u6211\u4eec\u8981\u52aa\u529b\u5b66\u4e60\u5566\uff01\u4eca\u5929\u6211\u7ed9\u5927\u5bb6\u5e26\u6765\uff0c\u611f\u5174\u8da3\u7684\u670b\u53cb\u8bf7\u7ee7\u7eed\u770b\u4e0b\u53bb\u5427\uff01\u4e0b\u6587\u4e2d\u7684\u5185\u5bb9\u6211\u4eec\u4e3b\u8981\u4f1a\u6d89\u53ca\u5230\u7b49\u7b49\u77e5\u8bc6\u70b9\uff0c\u5982\u679c\u5728\u9605\u8bfb\u672c\u6587\u8fc7\u7a0b\u4e2d\u6709\u9047\u5230\u4e0d\u6e05\u695a\u7684\u5730\u65b9\uff0c\u6b22\u8fce\u7559\u8a00\u5440\uff01\u6211\u4eec\u4e00\u8d77\u8ba8\u8bba\uff0c\u4e00\u8d77\u5b66\u4e60\uff01<\/p>\n

\u4ee5MySQL\u67e5\u8be2\uff1a\u7cbe\u51c6\u7b5b\u9009\u6570\u636e\u7684\u65b9\u6cd5\u8be6\u89e3<\/p>\n

\u5728\u6570\u636e\u5e93\u7ba1\u7406\u4e2d\uff0c\u7ecf\u5e38\u9700\u8981\u6839\u636e\u7279\u5b9a\u6761\u4ef6\u6765\u7b5b\u9009\u51fa\u9700\u8981\u7684\u6570\u636e\u3002MySQL\u4f5c\u4e3a\u4e00\u79cd\u6d41\u884c\u7684\u6570\u636e\u5e93\u7ba1\u7406\u7cfb\u7edf\uff0c\u63d0\u4f9b\u4e86\u4e30\u5bcc\u7684\u67e5\u8be2\u529f\u80fd\uff0c\u80fd\u591f\u5e2e\u52a9\u7528\u6237\u9ad8\u6548\u5730\u83b7\u53d6\u6570\u636e\u3002\u672c\u6587\u5c06\u4ece\u57fa\u672c\u7684SELECT\u8bed\u53e5\u5f00\u59cb\uff0c\u8be6\u7ec6\u4ecb\u7ecdMySQL\u4e2d\u5982\u4f55\u7cbe\u51c6\u7b5b\u9009\u6570\u636e\u7684\u65b9\u6cd5\uff0c\u540c\u65f6\u914d\u4ee5\u5177\u4f53\u7684\u4ee3\u7801\u793a\u4f8b\u3002<\/p>\n

\u4e00\u3001\u57fa\u672c\u7684SELECT\u8bed\u53e5<\/p>\n

\u5728MySQL\u4e2d\uff0c\u4f7f\u7528SELECT\u8bed\u53e5\u8fdb\u884c\u6570\u636e\u67e5\u8be2\u662f\u6700\u57fa\u672c\u7684\u64cd\u4f5c\u3002\u5176\u57fa\u672c\u8bed\u6cd5\u5982\u4e0b\uff1a<\/p>\n

SELECT \u5217\u540d1, \u5217\u540d2, ...\nFROM \u8868\u540d\nWHERE \u6761\u4ef6;<\/pre>\n
\u5176\u4e2d\uff0cSELECT\u7528\u4e8e\u6307\u5b9a\u9700\u8981\u67e5\u8be2\u7684\u5217\uff0cFROM\u7528\u4e8e\u6307\u5b9a\u8981\u67e5\u8be2\u7684\u8868\uff0cWHERE\u7528\u4e8e\u6307\u5b9a\u7b5b\u9009\u6761\u4ef6\u3002\u4e0b\u9762\u662f\u4e00\u4e2a\u7b80\u5355\u7684\u793a\u4f8b\uff1a<\/p>\n
SELECT id, name, age\nFROM student\nWHERE age > 18;<\/pre>\n
\u4ee5\u4e0a\u4ee3\u7801\u8868\u793a\u4ecestudent\u8868\u4e2d\u9009\u53d6id\u3001name\u548cage\u5217\uff0c\u4e14age\u5927\u4e8e18\u7684\u8bb0\u5f55\u3002<\/p>\n
\u4e8c\u3001\u4f7f\u7528\u6bd4\u8f83\u64cd\u4f5c\u7b26\u7b5b\u9009\u6570\u636e<\/p>\n
MySQL\u4e2d\u5e38\u7528\u7684\u6bd4\u8f83\u64cd\u4f5c\u7b26\u6709\uff1a\u7b49\u4e8e(=)\u3001\u5927\u4e8e(>)\u3001\u5c0f\u4e8e(<)\u3001\u5927\u4e8e\u7b49\u4e8e(>=)\u3001\u5c0f\u4e8e\u7b49\u4e8e(<=)\u3001\u4e0d\u7b49\u4e8e(!=\u6216<>)\u7b49\u3002\u4e0b\u9762\u662f\u4e00\u4e2a\u793a\u4f8b\uff1a<\/p>\n
SELECT id, name\nFROM employee\nWHERE salary > 50000 AND department = 'IT';<\/pre>\n
\u4ee5\u4e0a\u4ee3\u7801\u4e2d\uff0c\u7b5b\u9009\u4e86salary\u5927\u4e8e50000\u4e14department\u4e3a’IT’\u7684employee\u8bb0\u5f55\u3002<\/p>\n
\u4e09\u3001\u4f7f\u7528\u903b\u8f91\u64cd\u4f5c\u7b26\u7b5b\u9009\u6570\u636e<\/p>\n
\u5728MySQL\u4e2d\uff0c\u5e38\u7528\u7684\u903b\u8f91\u64cd\u4f5c\u7b26\u6709\uff1aAND\u3001OR\u3001NOT\u3002\u53ef\u4ee5\u4f7f\u7528\u8fd9\u4e9b\u903b\u8f91\u64cd\u4f5c\u7b26\u6839\u636e\u4e0d\u540c\u7684\u6761\u4ef6\u7ec4\u5408\u6765\u7b5b\u9009\u6570\u636e\u3002\u4ee5\u4e0b\u662f\u4e00\u4e2a\u793a\u4f8b\uff1a<\/p>\n
SELECT id, name\nFROM product\nWHERE (category = 'Electronics' OR category = 'Appliances') AND price < 1000;<\/pre>\n
\u4ee5\u4e0a\u4ee3\u7801\u4e2d\uff0c\u7b5b\u9009\u4e86category\u4e3a’Electronics’\u6216’Appliances’\u4e14price\u5c0f\u4e8e1000\u7684product\u8bb0\u5f55\u3002<\/p>\n
\u56db\u3001\u4f7f\u7528\u901a\u914d\u7b26\u8fdb\u884c\u6a21\u7cca\u67e5\u8be2<\/p>\n
MySQL\u63d0\u4f9b\u4e86\u901a\u914d\u7b26\u6765\u8fdb\u884c\u6a21\u7cca\u67e5\u8be2\uff0c\u5e38\u7528\u7684\u901a\u914d\u7b26\u6709\uff1a%\u548c_\u3002%\u8868\u793a\u96f6\u4e2a\u6216\u591a\u4e2a\u5b57\u7b26\uff0c_\u8868\u793a\u4e00\u4e2a\u5b57\u7b26\u3002\u4ee5\u4e0b\u662f\u4e00\u4e2a\u793a\u4f8b\uff1a<\/p>\n
SELECT id, name\nFROM customer\nWHERE name LIKE 'A%';<\/pre>\n
\u4ee5\u4e0a\u4ee3\u7801\u4e2d\uff0c\u7b5b\u9009\u4e86name\u4ee5\u5b57\u6bcd’A’\u5f00\u5934\u7684customer\u8bb0\u5f55\u3002<\/p>\n
\u4e94\u3001\u4f7f\u7528IN\u548cNOT IN\u7b5b\u9009\u6570\u636e<\/p>\n
\u5728MySQL\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528IN\u548cNOT IN\u6765\u7b5b\u9009\u6ee1\u8db3\u4e00\u7cfb\u5217\u6761\u4ef6\u7684\u6570\u636e\u3002\u4ee5\u4e0b\u662f\u4e00\u4e2a\u793a\u4f8b\uff1a<\/p>\n
SELECT id, name\nFROM product\nWHERE category IN ('Electronics', 'Appliances');<\/pre>\n
\u4ee5\u4e0a\u4ee3\u7801\u4e2d\uff0c\u7b5b\u9009\u4e86category\u4e3a’Electronics’\u6216’Appliances’\u7684product\u8bb0\u5f55\u3002<\/p>\n
\u516d\u3001\u4f7f\u7528\u805a\u5408\u51fd\u6570\u8fdb\u884c\u7b5b\u9009<\/p>\n
\u6700\u540e\uff0cMySQL\u8fd8\u63d0\u4f9b\u4e86\u4e00\u4e9b\u805a\u5408\u51fd\u6570\uff0c\u5982COUNT\u3001SUM\u3001AVG\u3001MAX\u3001MIN\u7b49\uff0c\u53ef\u4ee5\u5728\u7b5b\u9009\u6570\u636e\u7684\u8fc7\u7a0b\u4e2d\u8fdb\u884c\u6570\u636e\u805a\u5408\u3002\u4ee5\u4e0b\u662f\u4e00\u4e2a\u793a\u4f8b\uff1a<\/p>\n
SELECT department, AVG(salary) as average_salary\nFROM employee\nGROUP BY department\nHAVING AVG(salary) > 50000;<\/pre>\n
\u4ee5\u4e0a\u4ee3\u7801\u4e2d\uff0c\u6309\u7167\u90e8\u95e8\u5bf9\u5458\u5de5\u7684\u5e73\u5747\u5de5\u8d44\u8fdb\u884c\u8ba1\u7b97\uff0c\u5e76\u7b5b\u9009\u4e86\u5e73\u5747\u5de5\u8d44\u5927\u4e8e50000\u7684\u90e8\u95e8\u3002<\/p>\n
\u603b\u7ed3\uff1a<\/p>\n
\u901a\u8fc7\u672c\u6587\u7684\u4ecb\u7ecd\uff0c\u6211\u4eec\u8be6\u7ec6\u8bb2\u89e3\u4e86MySQL\u4e2d\u5982\u4f55\u4f7f\u7528SELECT\u8bed\u53e5\u548c\u5404\u79cd\u64cd\u4f5c\u7b26\u6765\u7cbe\u51c6\u7b5b\u9009\u6570\u636e\u7684\u65b9\u6cd5\u3002\u540c\u65f6\uff0c\u63d0\u4f9b\u4e86\u5177\u4f53\u7684\u4ee3\u7801\u793a\u4f8b\uff0c\u5e0c\u671b\u80fd\u591f\u5e2e\u52a9\u8bfb\u8005\u66f4\u52a0\u7075\u6d3b\u548c\u9ad8\u6548\u5730\u8fdb\u884c\u6570\u636e\u67e5\u8be2\u64cd\u4f5c\u3002\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\uff0c\u6839\u636e\u5177\u4f53\u9700\u6c42\u7075\u6d3b\u8fd0\u7528\u8fd9\u4e9b\u67e5\u8be2\u65b9\u6cd5\uff0c\u53ef\u4ee5\u66f4\u597d\u5730\u5904\u7406\u6570\u636e\uff0c\u63d0\u9ad8\u5de5\u4f5c\u6548\u7387\u3002<\/p>\n
\u4ee5\u4e0a\u4e3a\u672c\u6587\u7684\u5168\u90e8\u5185\u5bb9\uff0c\u5e0c\u671b\u80fd\u5bf9\u8bfb\u8005\u6709\u6240\u5e2e\u52a9\u3002<\/p>\n
\u6587\u4e2d\u5173\u4e8emysql,\u67e5\u8be2,\u7b5b\u9009\u7684\u77e5\u8bc6\u4ecb\u7ecd\uff0c\u5e0c\u671b\u5bf9\u4f60\u7684\u5b66\u4e60\u6709\u6240\u5e2e\u52a9\uff01\u82e5\u662f\u53d7\u76ca\u532a\u6d45\uff0c\u90a3\u5c31\u52a8\u52a8\u9f20\u6807\u6536\u85cf\u8fd9\u7bc7\u300aMySQL\u67e5\u8be2\u6280\u5de7\uff1a\u7cbe\u786e\u8fc7\u6ee4\u6570\u636e\u7684\u5168\u9762\u6307\u5357\u300b\u6587\u7ae0\u5427\uff0c\u4e5f\u53ef\u5173\u6ce8\u4e3b\u673a\u5b9d\u8d1d\u516c\u4f17\u53f7\u4e86\u89e3\u76f8\u5173\u6280\u672f\u6587\u7ae0\u3002<\/p>\n
\n
\n <\/dt>\n<\/dl>\n","protected":false},"excerpt":{"rendered":"
MySQL\u67e5\u8be2\u6280\u5de7\uff1a\u7cbe\u786e\u8fc7\u6ee4\u6570\u636e...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-199765","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/199765","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=199765"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/199765\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=199765"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=199765"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=199765"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}