{"id":200398,"date":"2025-05-06T12:34:04","date_gmt":"2025-05-06T04:34:04","guid":{"rendered":"https:\/\/server.hk\/cnblog\/200398\/"},"modified":"2025-05-06T12:34:04","modified_gmt":"2025-05-06T04:34:04","slug":"mysql-%e7%bb%88%e7%ab%af%ef%bc%9a%e6%9b%b4%e6%94%b9%e8%a1%a8%e3%80%81%e5%ad%97%e7%ac%a6%e9%9b%86%e5%92%8c%e5%88%a0%e9%99%a4","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/200398\/","title":{"rendered":"MySQL \u7ec8\u7aef\uff1a\u66f4\u6539\u8868\u3001\u5b57\u7b26\u96c6\u548c\u5220\u9664"},"content":{"rendered":"

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

MySQL \u7ec8\u7aef\uff1a\u66f4\u6539\u8868\u3001\u5b57\u7b26\u96c6\u548c\u5220\u9664<\/h1>\n

\u54c8\u55bd\uff01\u5927\u5bb6\u597d\uff0c\u5f88\u9ad8\u5174\u53c8\u89c1\u9762\u4e86\uff0c\u6211\u662f\u4e3b\u673a\u5b9d\u8d1d\u7684\u4e00\u540d\u4f5c\u8005\uff0c\u4eca\u5929\u7531\u6211\u7ed9\u5927\u5bb6\u5e26\u6765\u4e00\u7bc7\uff0c\u672c\u6587\u4e3b\u8981\u4f1a\u8bb2\u5230\u7b49\u7b49\u77e5\u8bc6\u70b9\uff0c\u5e0c\u671b\u5927\u5bb6\u4e00\u8d77\u5b66\u4e60\u8fdb\u6b65\uff0c\u4e5f\u6b22\u8fce\u5927\u5bb6\u5173\u6ce8\u3001\u70b9\u8d5e\u3001\u6536\u85cf\u3001\u8f6c\u53d1! \u4e0b\u9762\u5c31\u4e00\u8d77\u6765\u770b\u770b\u5427\uff01<\/p>\n

<\/p>\n

\u4fee\u6539\u8868 <\/h2>\n

mysql \u4e2d\u5e26\u6709 modify \u5b50\u53e5\u7684 alter table \u547d\u4ee4\u7528\u4e8e\u66f4\u6539\u8868\u4e2d\u73b0\u6709\u5217\u7684\u5b9a\u4e49\u3002\u547d\u4ee4\u7ed3\u6784\u5982\u4e0b\uff1a<\/p>\n

alter table table_name modify column_name data_type [options];\n<\/pre>\n
    \n
  •  table_name: \u6b63\u5728\u4fee\u6539\u5217\u7684\u8868\u7684\u540d\u79f0\u3002<\/li>\n
  •  column_name\uff1a\u8981\u4fee\u6539\u7684\u5217\u7684\u540d\u79f0\u3002<\/li>\n
  •  data_type\uff1a\u5217\u7684\u65b0\u6570\u636e\u7c7b\u578b\u3002<\/li>\n
  •  [options]\uff1a\u4efb\u4f55\u5176\u4ed6\u53ef\u9009\u89c4\u8303\uff0c\u4f8b\u5982 not null\u3001default \u503c\u7b49<\/li>\n<\/ul>\n
    \u793a\u4f8b<\/strong><\/p>\n
    \u5047\u8bbe users \u8868\u4e2d\u6709\u4e00\u4e2a int \u7c7b\u578b\u7684\u5e74\u9f84\u5217\uff0c\u5e76\u4e14\u60a8\u60f3\u5c06\u5176\u66f4\u6539\u4e3a int(3)\uff0c\u9ed8\u8ba4\u503c\u4e3a 18\u3002\u547d\u4ee4\u4e3a\uff1a<\/p>\n
    alter table users modify age int(3) default 18;\n<\/pre>\n
    \u6b64\u547d\u4ee4\u5c06age\u5217\u7684\u6570\u636e\u7c7b\u578b\u66f4\u6539\u4e3aint(3)\uff0c\u5e76\u5c06\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u4e3a18\u3002<\/p>\n
     \u66f4\u6539\u8868\u66f4\u6539 <\/h2>\n
    mysql \u4e2d\u5e26\u6709 change \u5b50\u53e5\u7684 alter table \u547d\u4ee4\u7528\u4e8e\u91cd\u547d\u540d\u5217\u5e76\u66f4\u6539\u5176\u6570\u636e\u7c7b\u578b\u6216\u5c5e\u6027\u3002\u547d\u4ee4\u7684\u7ed3\u6784\u5982\u4e0b\uff1a<\/p>\n
    alter table table_name change old_column_name new_column_name data_type [options];\n<\/pre>\n
      \n
    •  table_name: \u5217\u6240\u5728\u8868\u7684\u540d\u79f0\u3002<\/li>\n
    •  old_column_name\uff1a\u8981\u4fee\u6539\u7684\u5217\u7684\u5f53\u524d\u540d\u79f0\u3002<\/li>\n
    •  new_column_name\uff1a\u5217\u7684\u65b0\u540d\u79f0\u3002<\/li>\n
    •  data_type\uff1a\u5217\u7684\u65b0\u6570\u636e\u7c7b\u578b\u3002<\/li>\n
    •  [\u9009\u9879]\uff1a\u4efb\u4f55\u9644\u52a0\u89c4\u8303\uff0c\u4f8b\u5982 not null\u3001default \u503c\u7b49<\/li>\n<\/ul>\n
      \u793a\u4f8b<\/strong><\/p>\n
      \u5047\u8bbe users \u8868\u4e2d\u6709\u4e00\u4e2a\u7c7b\u578b\u4e3a int \u7684 age \u5217\uff0c\u5e76\u4e14\u60a8\u60f3\u5c06\u5176\u91cd\u547d\u540d\u4e3a current_age \u5e76\u5c06\u5176\u66f4\u6539\u4e3a int(3)\uff0c\u9ed8\u8ba4\u503c\u4e3a 18\u3002\u547d\u4ee4\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n
      alter table users change age current_age int(3) default 18;\n<\/pre>\n
      \u6b64\u547d\u4ee4\u5c06age\u5217\u91cd\u547d\u540d\u4e3acurrent_age\uff0c\u5c06\u5176\u6570\u636e\u7c7b\u578b\u66f4\u6539\u4e3aint(3)\uff0c\u5e76\u5c06\u9ed8\u8ba4\u503c\u8bbe\u7f6e\u4e3a18\u3002<\/p>\n
       \u66f4\u6539\u8868\u91cd\u547d\u540d\u4e3a <\/h2>\n
      mysql \u4e2d\u5e26\u6709 rename to \u5b50\u53e5\u7684 alter table \u547d\u4ee4\u7528\u4e8e\u91cd\u547d\u540d\u8868\u3002\u8bed\u6cd5\u5982\u4e0b\uff1a<\/p>\n
      alter table old_table_name rename to new_table_name;\n<\/pre>\n
        \n
      •  old_table_name\uff1a\u8981\u91cd\u547d\u540d\u7684\u8868\u7684\u5f53\u524d\u540d\u79f0\u3002<\/li>\n
      •  new_table_name\uff1a\u8868\u7684\u65b0\u540d\u79f0\u3002<\/li>\n<\/ul>\n
        \u793a\u4f8b<\/strong><\/p>\n
        \u5047\u8bbe\u60a8\u6709\u4e00\u4e2a\u540d\u4e3a users \u7684\u8868\uff0c\u5e76\u4e14\u60a8\u60f3\u5c06\u5176\u91cd\u547d\u540d\u4e3acustomers\u3002\u547d\u4ee4\u662f\uff1a<\/p>\n
        alter table users rename to customers;\n<\/pre>\n
        \u6b64\u547d\u4ee4\u5c06\u8868 users \u91cd\u547d\u540d\u4e3acustomers\u3002<\/p>\n
         \u66f4\u6539\u8868\u8f6c\u6362\u4e3a\u5b57\u7b26\u96c6 <\/h2>\n
        mysql \u4e2d\u7684 alter table … convert to character set \u547d\u4ee4\u7528\u4e8e\u66f4\u6539\u6574\u4e2a\u8868\u7684\u5b57\u7b26\u96c6\u548c\u6392\u5e8f\u89c4\u5219\u3002\u8bed\u6cd5\u5982\u4e0b\uff1a<\/p>\n
        alter table table_name convert to character set charset_name [collate collation_name];\n<\/pre>\n
          \n
        •  table_name\uff1a\u8981\u66f4\u6539\u5176\u5b57\u7b26\u96c6\u548c\u6392\u5e8f\u89c4\u5219\u7684\u8868\u7684\u540d\u79f0\u3002<\/li>\n
        •  charset_name\uff1a\u8868\u7684\u65b0\u5b57\u7b26\u96c6\uff0c\u4f8b\u5982utf8mb4\u3002<\/li>\n
        •  [collate collat\u200b\u200bion_name]\uff1a\u7528\u4e8e\u6307\u5b9a\u6392\u5e8f\u89c4\u5219\u7684\u53ef\u9009\u53c2\u6570\uff08\u4f8b\u5982 utf8mb4_unicode_ci\uff09\u3002\u5982\u679c\u7701\u7565\uff0c\u5c06\u4f7f\u7528\u6307\u5b9a\u5b57\u7b26\u96c6\u7684\u9ed8\u8ba4\u6392\u5e8f\u89c4\u5219\u3002<\/li>\n<\/ul>\n
          \u793a\u4f8b<\/strong><\/p>\n
          \u5982\u679c\u4f60\u60f3\u5c06customers\u8868\u7684\u5b57\u7b26\u96c6\u66f4\u6539\u4e3autf8mb4\u53ca\u5176\u9ed8\u8ba4\u6392\u5e8f\u89c4\u5219\uff0c\u4f60\u53ef\u4ee5\u4f7f\u7528\uff1a<\/p>\n
          alter table customers convert to character set utf8mb4;\n<\/pre>\n
          \u6216\u8005\uff0c\u5982\u679c\u60a8\u60f3\u6307\u5b9a\u7279\u5b9a\u7684\u6392\u5e8f\u89c4\u5219\uff0c\u4f8b\u5982 utf8mb4_unicode_ci\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\uff1a<\/p>\n
          alter table customers convert to character set utf8mb4 collate utf8mb4_unicode_ci;\n<\/pre>\n
          \u6b64\u547d\u4ee4\u5c06\u8868\u4e2d\u7684\u6240\u6709\u6587\u672c\u5217\u66f4\u65b0\u4e3a\u6307\u5b9a\u7684\u5b57\u7b26\u96c6\u548c\u6392\u5e8f\u89c4\u5219\u3002<\/p>\n
           \u6389\u843d\u8868 <\/h2>\n
          sql \u4e2d\u7684 drop table \u547d\u4ee4\u7528\u4e8e\u4ece\u6570\u636e\u5e93\u4e2d\u6c38\u4e45\u5220\u9664\u8868\u53ca\u5176\u6240\u6709\u6570\u636e\u3002\u8bed\u6cd5\u5982\u4e0b\uff1a<\/p>\n
          drop table table_name;\n<\/pre>\n
            \n
          •  table_name\uff1a\u8981\u5220\u9664\u7684\u8868\u7684\u540d\u79f0\u3002<\/li>\n<\/ul>\n
            \u793a\u4f8b<\/strong><\/p>\n
            \u5982\u679c\u8981\u5220\u9664\u540d\u4e3acustomers\u7684\u8868\uff0c\u547d\u4ee4\u4e3a\uff1a<\/p>\n
            DROP TABLE customers;\n<\/pre>\n
            \n
            \u8b66\u544a<\/strong>\uff1a\u4f7f\u7528 drop table \u5c06\u6c38\u4e45\u5220\u9664\u8868\u53ca\u5176\u6240\u6709\u6570\u636e\u3002\u6b64\u64cd\u4f5c\u65e0\u6cd5\u64a4\u6d88\uff0c\u56e0\u6b64\u8bf7\u786e\u4fdd\u5728\u6267\u884c\u6b64\u547d\u4ee4\u4e4b\u524d\u5907\u4efd\u6240\u6709\u91cd\u8981\u6570\u636e\u3002<\/p>\n<\/blockquote>\n
            \u4eca\u5929\u5173\u4e8e\u300aMySQL \u7ec8\u7aef\uff1a\u66f4\u6539\u8868\u3001\u5b57\u7b26\u96c6\u548c\u5220\u9664\u300b\u7684\u5185\u5bb9\u4ecb\u7ecd\u5c31\u5230\u6b64\u7ed3\u675f\uff0c\u5982\u679c\u6709\u4ec0\u4e48\u7591\u95ee\u6216\u8005\u5efa\u8bae\uff0c\u53ef\u4ee5\u5728\u4e3b\u673a\u5b9d\u8d1d\u516c\u4f17\u53f7\u4e0b\u591a\u591a\u56de\u590d\u4ea4\u6d41\uff1b\u6587\u4e2d\u82e5\u6709\u4e0d\u6b63\u4e4b\u5904\uff0c\u4e5f\u5e0c\u671b\u56de\u590d\u7559\u8a00\u4ee5\u544a\u77e5\uff01<\/p>\n
             \u7248\u672c\u58f0\u660e \u672c\u6587\u8f6c\u8f7d\u4e8e\uff1adev.to \u5982\u6709\u4fb5\u72af\uff0c\u8bf7\u8054\u7cfb \u5220\u9664 <\/p>\n
            \n
            \n <\/dt>\n<\/dl>\n","protected":false},"excerpt":{"rendered":"
            MySQL \u7ec8\u7aef\uff1a\u66f4\u6539\u8868\u3001\u5b57\u7b26\u96c6...<\/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-200398","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/200398","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=200398"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/200398\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=200398"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=200398"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=200398"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}