{"id":172683,"date":"2024-11-07T15:10:27","date_gmt":"2024-11-07T07:10:27","guid":{"rendered":"https:\/\/server.hk\/cnblog\/172683\/"},"modified":"2024-11-07T15:10:28","modified_gmt":"2024-11-07T07:10:28","slug":"%e5%a6%82%e4%bd%95%e6%9f%a5%e8%a9%a2%e4%b8%a6%e5%88%aa%e9%99%a4%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e7%9a%84%e9%87%8d%e8%a4%87%e6%95%b8%e6%93%9a%ef%bc%9f-%e6%9f%a5%e8%a9%a2%e6%95%b8%e6%93%9a%e5%ba%ab","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/172683\/","title":{"rendered":"\u5982\u4f55\u67e5\u8a62\u4e26\u522a\u9664\u6578\u64da\u5eab\u4e2d\u7684\u91cd\u8907\u6578\u64da\uff1f (\u67e5\u8a62\u6578\u64da\u5eab\u91cd\u8907\u6578\u64da)"},"content":{"rendered":"

\u5982\u4f55\u67e5\u8a62\u4e26\u522a\u9664\u6578\u64da\u5eab\u4e2d\u7684\u91cd\u8907\u6578\u64da\uff1f<\/h1>\n

\u5728\u6578\u64da\u5eab\u7ba1\u7406\u4e2d\uff0c\u91cd\u8907\u6578\u64da\u662f\u4e00\u500b\u5e38\u898b\u7684\u554f\u984c\uff0c\u9019\u4e0d\u50c5\u6703\u5f71\u97ff\u6578\u64da\u7684\u5b8c\u6574\u6027\uff0c\u9084\u6703\u5c0e\u81f4\u67e5\u8a62\u6548\u7387\u964d\u4f4e\u3002\u672c\u6587\u5c07\u63a2\u8a0e\u5982\u4f55\u67e5\u8a62\u4e26\u522a\u9664\u6578\u64da\u5eab\u4e2d\u7684\u91cd\u8907\u6578\u64da\uff0c\u5e6b\u52a9\u60a8\u4fdd\u6301\u6578\u64da\u7684\u6574\u6f54\u548c\u6e96\u78ba\u3002<\/p>\n

\u4ec0\u9ebc\u662f\u91cd\u8907\u6578\u64da\uff1f<\/h2>\n

\u91cd\u8907\u6578\u64da\u662f\u6307\u5728\u6578\u64da\u5eab\u4e2d\u5b58\u5728\u591a\u689d\u76f8\u540c\u6216\u76f8\u4f3c\u7684\u8a18\u9304\u3002\u9019\u4e9b\u91cd\u8907\u7684\u8a18\u9304\u53ef\u80fd\u662f\u7531\u65bc\u591a\u6b21\u8f38\u5165\u76f8\u540c\u6578\u64da\u3001\u6578\u64da\u5c0e\u5165\u904e\u7a0b\u4e2d\u7684\u932f\u8aa4\u6216\u7cfb\u7d71\u6574\u5408\u6642\u7684\u6578\u64da\u885d\u7a81\u6240\u9020\u6210\u7684\u3002\u91cd\u8907\u6578\u64da\u4e0d\u50c5\u6d6a\u8cbb\u5b58\u5132\u7a7a\u9593\uff0c\u9084\u53ef\u80fd\u5c0e\u81f4\u5831\u544a\u548c\u5206\u6790\u7d50\u679c\u7684\u4e0d\u6e96\u78ba\u3002<\/p>\n

\u67e5\u8a62\u91cd\u8907\u6578\u64da<\/h2>\n

\u5728\u67e5\u8a62\u91cd\u8907\u6578\u64da\u4e4b\u524d\uff0c\u9996\u5148\u9700\u8981\u78ba\u5b9a\u54ea\u4e9b\u5b57\u6bb5\u662f\u7528\u4f86\u5224\u65b7\u91cd\u8907\u7684\u3002\u901a\u5e38\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528 SQL \u7684 GROUP BY<\/code> \u548c HAVING<\/code> \u5b50\u53e5\u4f86\u67e5\u8a62\u91cd\u8907\u7684\u8a18\u9304\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff1a<\/p>\n

SELECT column_name, COUNT(*)\nFROM table_name\nGROUP BY column_name\nHAVING COUNT(*) > 1;<\/code><\/pre>\n
\u5728\u9019\u500b\u67e5\u8a62\u4e2d\uff0ccolumn_name<\/code> \u662f\u60a8\u8981\u6aa2\u67e5\u91cd\u8907\u7684\u5b57\u6bb5\uff0ctable_name<\/code> \u662f\u60a8\u8981\u67e5\u8a62\u7684\u6578\u64da\u8868\u3002\u9019\u500b\u67e5\u8a62\u5c07\u8fd4\u56de\u6240\u6709\u91cd\u8907\u7684\u8a18\u9304\u53ca\u5176\u51fa\u73fe\u7684\u6b21\u6578\u3002<\/p>\n
\u522a\u9664\u91cd\u8907\u6578\u64da<\/h2>\n
\u4e00\u65e6\u67e5\u8a62\u51fa\u91cd\u8907\u6578\u64da\uff0c\u63a5\u4e0b\u4f86\u7684\u6b65\u9a5f\u662f\u522a\u9664\u9019\u4e9b\u91cd\u8907\u7684\u8a18\u9304\u3002\u522a\u9664\u91cd\u8907\u6578\u64da\u7684\u65b9\u6cd5\u6709\u591a\u7a2e\uff0c\u4ee5\u4e0b\u662f\u5e7e\u7a2e\u5e38\u898b\u7684\u65b9\u6cd5\uff1a<\/p>\n
\u65b9\u6cd5\u4e00\uff1a\u4f7f\u7528\u5b50\u67e5\u8a62<\/h3>\n
\u60a8\u53ef\u4ee5\u4f7f\u7528\u5b50\u67e5\u8a62\u4f86\u522a\u9664\u91cd\u8907\u7684\u8a18\u9304\u3002\u4ee5\u4e0b\u662f\u4e00\u500b\u793a\u4f8b\uff1a<\/p>\n
DELETE FROM table_name\nWHERE id NOT IN (\n    SELECT MIN(id)\n    FROM table_name\n    GROUP BY column_name\n);<\/code><\/pre>\n
\u5728\u9019\u500b\u67e5\u8a62\u4e2d\uff0cid<\/code> \u662f\u6bcf\u689d\u8a18\u9304\u7684\u552f\u4e00\u6a19\u8b58\u7b26\uff0c\u9019\u6a23\u53ef\u4ee5\u4fdd\u7559\u6bcf\u7d44\u91cd\u8907\u8a18\u9304\u4e2d\u7684\u4e00\u689d\uff0c\u4e26\u522a\u9664\u5176\u9918\u7684\u91cd\u8907\u8a18\u9304\u3002<\/p>\n
\u65b9\u6cd5\u4e8c\uff1a\u4f7f\u7528\u81e8\u6642\u8868<\/h3>\n
\u53e6\u4e00\u7a2e\u65b9\u6cd5\u662f\u4f7f\u7528\u81e8\u6642\u8868\u4f86\u5b58\u5132\u552f\u4e00\u7684\u8a18\u9304\uff0c\u7136\u5f8c\u7528\u9019\u4e9b\u552f\u4e00\u8a18\u9304\u66ff\u63db\u539f\u59cb\u8868\u3002\u4ee5\u4e0b\u662f\u6b65\u9a5f\uff1a<\/p>\n
    \n
  1. \u5275\u5efa\u4e00\u500b\u81e8\u6642\u8868\u4f86\u5b58\u5132\u552f\u4e00\u8a18\u9304\uff1a<\/li>\n
    CREATE TABLE temp_table AS\n    SELECT DISTINCT *\n    FROM table_name;<\/code><\/pre>\n
  2. \u522a\u9664\u539f\u59cb\u8868\u4e2d\u7684\u6240\u6709\u8a18\u9304\uff1a<\/li>\n
    DELETE FROM table_name;<\/code><\/pre>\n
  3. \u5c07\u81e8\u6642\u8868\u4e2d\u7684\u552f\u4e00\u8a18\u9304\u63d2\u5165\u56de\u539f\u59cb\u8868\uff1a<\/li>\n
    INSERT INTO table_name\n    SELECT * FROM temp_table;<\/code><\/pre>\n
  4. \u522a\u9664\u81e8\u6642\u8868\uff1a<\/li>\n
    DROP TABLE temp_table;<\/code><\/pre>\n<\/ol>\n
    \u7d50\u8ad6<\/h2>\n
    \u67e5\u8a62\u4e26\u522a\u9664\u6578\u64da\u5eab\u4e2d\u7684\u91cd\u8907\u6578\u64da\u662f\u4e00\u500b\u91cd\u8981\u7684\u6578\u64da\u7ba1\u7406\u4efb\u52d9\u3002\u901a\u904e\u4f7f\u7528 SQL \u67e5\u8a62\uff0c\u60a8\u53ef\u4ee5\u8f15\u9b06\u8b58\u5225\u548c\u6e05\u7406\u91cd\u8907\u7684\u8a18\u9304\uff0c\u5f9e\u800c\u63d0\u9ad8\u6578\u64da\u7684\u6e96\u78ba\u6027\u548c\u67e5\u8a62\u6548\u7387\u3002\u4fdd\u6301\u6578\u64da\u5eab\u7684\u6574\u6f54\u4e0d\u50c5\u6709\u52a9\u65bc\u63d0\u5347\u7cfb\u7d71\u6027\u80fd\uff0c\u9084\u80fd\u70ba\u696d\u52d9\u6c7a\u7b56\u63d0\u4f9b\u53ef\u9760\u7684\u6578\u64da\u652f\u6301\u3002<\/p>\n
    \u5982\u679c\u60a8\u9700\u8981\u66f4\u9ad8\u6548\u7684\u6578\u64da\u7ba1\u7406\u89e3\u6c7a\u65b9\u6848\uff0c\u8003\u616e\u4f7f\u7528\u9999\u6e2fVPS<\/a>\u6216\u4e91\u670d\u52a1\u5668<\/a>\u4f86\u63d0\u5347\u60a8\u7684\u6578\u64da\u8655\u7406\u80fd\u529b\u3002\u7121\u8ad6\u662f\u6578\u64da\u5eab\u7ba1\u7406\u9084\u662f\u5176\u4ed6\u61c9\u7528\uff0c\u9078\u64c7\u5408\u9069\u7684\u670d\u52a1\u5668<\/a>\u90fd\u80fd\u70ba\u60a8\u7684\u696d\u52d9\u5e36\u4f86\u66f4\u5927\u7684\u4fbf\u5229\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
    \u5b78\u7fd2\u5982\u4f55\u67e5\u8a62\u4e26\u522a\u9664\u6578\u64da\u5eab\u4e2d\u7684\u91cd\u8907\u6578\u64da\uff0c\u78ba\u4fdd\u6578\u64da\u7684\u6e96\u78ba\u6027\u548c\u5b8c\u6574\u6027\uff0c\u63d0\u5347\u6578\u64da\u7ba1\u7406\u6548\u7387\u3002<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-172683","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/172683","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"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=172683"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/172683\/revisions"}],"predecessor-version":[{"id":172684,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/172683\/revisions\/172684"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=172683"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=172683"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=172683"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}