{"id":200080,"date":"2025-05-06T08:04:57","date_gmt":"2025-05-06T00:04:57","guid":{"rendered":"https:\/\/server.hk\/cnblog\/200080\/"},"modified":"2025-05-06T08:04:57","modified_gmt":"2025-05-06T00:04:57","slug":"%e6%8e%a2%e7%b4%a2mysql%e7%b4%a2%e5%bc%95%ef%bc%9a%e6%8e%8c%e6%8f%a1unique%e7%b4%a2%e5%bc%95%e7%9a%84%e5%8a%9f%e8%83%bd%e5%92%8c%e4%bd%bf%e7%94%a8","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/200080\/","title":{"rendered":"\u63a2\u7d22MySQL\u7d22\u5f15\uff1a\u638c\u63e1unique\u7d22\u5f15\u7684\u529f\u80fd\u548c\u4f7f\u7528"},"content":{"rendered":"

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

\u63a2\u7d22MySQL\u7d22\u5f15\uff1a\u638c\u63e1unique\u7d22\u5f15\u7684\u529f\u80fd\u548c\u4f7f\u7528<\/h1>\n

\u5728\u6570\u636e\u5e93\u4e2d\uff0c\u7d22\u5f15\u662f\u63d0\u5347\u6570\u636e\u68c0\u7d22\u6548\u7387\u7684\u5173\u952e\u3002MySQL \u4e2d\u7684 unique \u7d22\u5f15\u662f\u4e00\u79cd\u7279\u6b8a\u7c7b\u578b\u7684\u7d22\u5f15\uff0c\u5b83\u786e\u4fdd\u7d22\u5f15\u5217\u4e2d\u7684\u503c\u552f\u4e00\uff0c\u5373\u6bcf\u4e2a\u503c\u4ec5\u51fa\u73b0\u4e00\u6b21\u3002unique \u7d22\u5f15\u65e2\u80fd\u4fdd\u8bc1\u6570\u636e\u7684\u552f\u4e00\u6027\uff0c\u53c8\u80fd\u63d0\u9ad8\u68c0\u7d22\u901f\u5ea6\uff0c\u8fd8\u80fd\u9632\u6b62\u91cd\u590d\u6570\u636e\u7684\u63d2\u5165\uff0c\u4ece\u800c\u63d0\u5347\u6570\u636e\u5e93\u6027\u80fd\u548c\u6570\u636e\u5b8c\u6574\u6027\u3002\u5728\u521b\u5efa\u8868\u6216\u5df2\u6709\u8868\u4e0a\u6dfb\u52a0 unique \u7d22\u5f15\u65f6\uff0c\u9700\u8981\u786e\u4fdd\u6570\u636e\u7684\u552f\u4e00\u6027\uff0c\u5426\u5219 MySQL \u4f1a\u629b\u51fa\u9519\u8bef\u3002<\/p>\n

MySQL\u7d22\u5f15\u8be6\u89e3\uff1a\u4e86\u89e3unique\u7d22\u5f15\u7684\u4f5c\u7528\u53ca\u7528\u6cd5<\/p>\n

\u5728\u6570\u636e\u5e93\u4e2d\uff0c\u7d22\u5f15\u662f\u4e00\u79cd\u6570\u636e\u7ed3\u6784\uff0c\u5b83\u53ef\u4ee5\u52a0\u5feb\u6570\u636e\u7684\u68c0\u7d22\u901f\u5ea6\u3002\u5728MySQL\u4e2d\uff0c\u7d22\u5f15\u662f\u4e00\u79cd\u5f88\u91cd\u8981\u7684\u6570\u636e\u7ed3\u6784\uff0c\u5b83\u53ef\u4ee5\u5e2e\u52a9\u6211\u4eec\u66f4\u9ad8\u6548\u5730\u68c0\u7d22\u6570\u636e\u3002\u8fd9\u7bc7\u6587\u7ae0\u5c06\u91cd\u70b9\u4ecb\u7ecdunique\u7d22\u5f15\uff0c\u8be6\u7ec6\u89e3\u91caunique\u7d22\u5f15\u7684\u4f5c\u7528\u53ca\u7528\u6cd5\uff0c\u5e76\u63d0\u4f9b\u5177\u4f53\u7684\u4ee3\u7801\u793a\u4f8b\uff0c\u5e2e\u52a9\u8bfb\u8005\u66f4\u597d\u5730\u7406\u89e3unique\u7d22\u5f15\u7684\u6982\u5ff5\u3002<\/p>\n

\u4ec0\u4e48\u662funique\u7d22\u5f15\uff1f<\/strong><\/p>\n

\u5728MySQL\u4e2d\uff0cunique\u7d22\u5f15\u662f\u4e00\u79cd\u7d22\u5f15\u7c7b\u578b\uff0c\u5b83\u7684\u4f5c\u7528\u662f\u4fdd\u8bc1\u7d22\u5f15\u5217\u4e2d\u7684\u503c\u662f\u552f\u4e00\u7684\uff0c\u5373\u6bcf\u4e2a\u503c\u53ea\u80fd\u51fa\u73b0\u4e00\u6b21\u3002\u4e0e\u666e\u901a\u7d22\u5f15\u4e0d\u540c\u7684\u662f\uff0cunique\u7d22\u5f15\u8981\u6c42\u88ab\u7d22\u5f15\u5217\u4e2d\u7684\u503c\u5728\u6574\u4e2a\u8868\u4e2d\u662f\u552f\u4e00\u7684\uff0c\u5e76\u4e14\u5141\u8bb8NULL\u503c\u7684\u51fa\u73b0\u3002<\/p>\n

unique\u7d22\u5f15\u7684\u4f5c\u7528<\/strong><\/p>\n

    \n
  1. \u4fdd\u8bc1\u552f\u4e00\u6027<\/strong>\uff1aunique\u7d22\u5f15\u80fd\u591f\u786e\u4fdd\u88ab\u7d22\u5f15\u5217\u4e2d\u7684\u503c\u662f\u552f\u4e00\u7684\uff0c\u907f\u514d\u51fa\u73b0\u91cd\u590d\u6570\u636e\uff0c\u4fdd\u8bc1\u6570\u636e\u7684\u552f\u4e00\u6027\u3002<\/li>\n
  2. \u63d0\u9ad8\u68c0\u7d22\u901f\u5ea6<\/strong>\uff1a\u7531\u4e8eunique\u7d22\u5f15\u80fd\u591f\u5e2e\u52a9\u6570\u636e\u5e93\u5feb\u901f\u5b9a\u4f4d\u5230\u9700\u8981\u68c0\u7d22\u7684\u6570\u636e\uff0c\u56e0\u6b64\u53ef\u4ee5\u52a0\u5feb\u6570\u636e\u68c0\u7d22\u7684\u901f\u5ea6\uff0c\u63d0\u9ad8\u67e5\u8be2\u6548\u7387\u3002<\/li>\n
  3. \u907f\u514d\u5197\u4f59\u6570\u636e\u7684\u63d2\u5165<\/strong>\uff1a\u901a\u8fc7unique\u7d22\u5f15\uff0c\u907f\u514d\u63d2\u5165\u91cd\u590d\u6570\u636e\uff0c\u63d0\u9ad8\u6570\u636e\u5e93\u7684\u6570\u636e\u5b8c\u6574\u6027\u3002<\/li>\n<\/ol>\n

    unique\u7d22\u5f15\u7684\u7528\u6cd5<\/strong><\/p>\n

    \u5728MySQL\u4e2d\uff0c\u6211\u4eec\u53ef\u4ee5\u5728\u521b\u5efa\u8868\u7684\u65f6\u5019\u6307\u5b9aunique\u7d22\u5f15\uff0c\u4e5f\u53ef\u4ee5\u5728\u5df2\u6709\u8868\u4e0a\u6dfb\u52a0unique\u7d22\u5f15\u3002\u4e0b\u9762\u5c06\u901a\u8fc7\u5177\u4f53\u7684\u4ee3\u7801\u793a\u4f8b\u6765\u8bf4\u660eunique\u7d22\u5f15\u7684\u7528\u6cd5\u3002<\/p>\n

    \u5728\u521b\u5efa\u8868\u65f6\u6307\u5b9aunique\u7d22\u5f15<\/strong><\/p>\n

    CREATE TABLE users (\n    id INT AUTO_INCREMENT PRIMARY KEY,\n    username VARCHAR(50) UNIQUE,\n    email VARCHAR(100) UNIQUE,\n    ...\n);<\/pre>\n
    \u5728\u4e0a\u9762\u7684\u4f8b\u5b50\u4e2d\uff0c\u6211\u4eec\u5728\u521b\u5efausers\u8868\u7684\u65f6\u5019\uff0c\u4e3ausername\u548cemail\u5217\u5206\u522b\u6dfb\u52a0\u4e86unique\u7d22\u5f15\uff0c\u4fdd\u8bc1\u4e86username\u548cemail\u7684\u552f\u4e00\u6027\u3002<\/p>\n
    \u5728\u5df2\u6709\u8868\u4e0a\u6dfb\u52a0unique\u7d22\u5f15<\/strong><\/p>\n
    CREATE UNIQUE INDEX idx_username ON users(username);<\/pre>\n
    \u901a\u8fc7\u4ee5\u4e0a\u4ee3\u7801\uff0c\u6211\u4eec\u5728\u5df2\u6709\u7684users\u8868\u4e0a\u6dfb\u52a0\u4e86\u4e00\u4e2a\u540d\u4e3aidx_username\u7684unique\u7d22\u5f15\uff0c\u4fdd\u8bc1\u4e86username\u5217\u7684\u552f\u4e00\u6027\u3002<\/p>\n
    \u6ce8\u610f\u4e8b\u9879<\/strong><\/p>\n
      \n
    1. \u5f53\u5728\u8868\u4e2d\u6dfb\u52a0\u4e86unique\u7d22\u5f15\u540e\uff0c\u5982\u679c\u5c1d\u8bd5\u63d2\u5165\u91cd\u590d\u7684\u6570\u636e\uff0cMySQL\u5c06\u4f1a\u629b\u51fa\u9519\u8bef\uff0c\u62d2\u7edd\u63d2\u5165\u91cd\u590d\u6570\u636e\u3002<\/li>\n
    2. \u5f53\u8868\u4e2d\u5df2\u6709\u6570\u636e\u65f6\uff0c\u6dfb\u52a0unique\u7d22\u5f15\u53ef\u80fd\u4f1a\u6d89\u53ca\u5230\u6570\u636e\u7684\u552f\u4e00\u6027\u7ea6\u675f\uff0c\u56e0\u6b64\u5728\u6dfb\u52a0unique\u7d22\u5f15\u4e4b\u524d\uff0c\u9700\u8981\u5148\u786e\u4fdd\u6570\u636e\u7684\u552f\u4e00\u6027\u3002<\/li>\n<\/ol>\n
      \u901a\u8fc7\u672c\u6587\u7684\u4ecb\u7ecd\uff0c\u76f8\u4fe1\u8bfb\u8005\u5bf9unique\u7d22\u5f15\u7684\u6982\u5ff5\u3001\u4f5c\u7528\u53ca\u7528\u6cd5\u6709\u4e86\u66f4\u6df1\u5165\u7684\u7406\u89e3\u3002\u5728\u5b9e\u9645\u7684\u6570\u636e\u5e93\u8bbe\u8ba1\u548c\u4f7f\u7528\u8fc7\u7a0b\u4e2d\uff0c\u5408\u7406\u5730\u4f7f\u7528unique\u7d22\u5f15\u53ef\u4ee5\u63d0\u9ad8\u6570\u636e\u5e93\u6027\u80fd\u3001\u4fdd\u8bc1\u6570\u636e\u7684\u5b8c\u6574\u6027\uff0c\u5e2e\u52a9\u6211\u4eec\u66f4\u9ad8\u6548\u5730\u7ba1\u7406\u6570\u636e\u3002\u5e0c\u671b\u8bfb\u8005\u901a\u8fc7\u672c\u6587\u7684\u9605\u8bfb\u53ef\u4ee5\u66f4\u597d\u5730\u5e94\u7528unique\u7d22\u5f15\u5230\u5b9e\u9645\u7684\u6570\u636e\u5e93\u9879\u76ee\u4e2d\u3002<\/p>\n
      \u7ec8\u4e8e\u4ecb\u7ecd\u5b8c\u5566\uff01\u5c0f\u4f19\u4f34\u4eec\uff0c\u8fd9\u7bc7\u5173\u4e8e\u300a\u63a2\u7d22MySQL\u7d22\u5f15\uff1a\u638c\u63e1unique\u7d22\u5f15\u7684\u529f\u80fd\u548c\u4f7f\u7528\u300b\u7684\u4ecb\u7ecd\u5e94\u8be5\u8ba9\u4f60\u6536\u83b7\u591a\u591a\u4e86\u5427\uff01\u6b22\u8fce\u5927\u5bb6\u6536\u85cf\u6216\u5206\u4eab\u7ed9\u66f4\u591a\u9700\u8981\u5b66\u4e60\u7684\u670b\u53cb\u5427~\u4e3b\u673a\u5b9d\u8d1d\u516c\u4f17\u53f7\u4e5f\u4f1a\u53d1\u5e03\u6570\u636e\u5e93\u76f8\u5173\u77e5\u8bc6\uff0c\u5feb\u6765\u5173\u6ce8\u5427\uff01<\/p>\n
      \n
      \n <\/dt>\n<\/dl>\n","protected":false},"excerpt":{"rendered":"
      \u63a2\u7d22MySQL\u7d22\u5f15\uff1a\u638c\u63e1uniq...<\/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-200080","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/200080","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=200080"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/200080\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=200080"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=200080"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=200080"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}