{"id":200580,"date":"2025-05-06T13:30:54","date_gmt":"2025-05-06T05:30:54","guid":{"rendered":"https:\/\/server.hk\/cnblog\/200580\/"},"modified":"2025-05-06T13:30:54","modified_gmt":"2025-05-06T05:30:54","slug":"%e6%95%b0%e6%8d%ae%e5%ba%93%e6%8a%a5%e9%94%99unknown-database%ef%bc%9a%e4%b8%ba%e4%bb%80%e4%b9%88%e6%88%91%e7%9a%84sql%e8%af%ad%e5%8f%a5%e6%97%a0%e6%b3%95%e6%89%be%e5%88%b0%e7%9b%ae","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/200580\/","title":{"rendered":"\u6570\u636e\u5e93\u62a5\u9519\u201cUnknown database\u201d\uff1a\u4e3a\u4ec0\u4e48\u6211\u7684SQL\u8bed\u53e5\u65e0\u6cd5\u627e\u5230\u76ee\u6807\u6570\u636e\u5e93\uff1f"},"content":{"rendered":"<p><b><\/b> <\/p>\n<h1>\u6570\u636e\u5e93\u62a5\u9519\u201cUnknown database\u201d\uff1a\u4e3a\u4ec0\u4e48\u6211\u7684SQL\u8bed\u53e5\u65e0\u6cd5\u627e\u5230\u76ee\u6807\u6570\u636e\u5e93\uff1f<\/h1>\n<p>\u4ece\u73b0\u5728\u5f00\u59cb\uff0c\u52aa\u529b\u5b66\u4e60\u5427\uff01\u672c\u6587\u4e3b\u8981\u8bb2\u89e3\u4e86\u7b49\u7b49\u76f8\u5173\u77e5\u8bc6\u70b9\uff0c\u6211\u4f1a\u5728\u4e3b\u673a\u5b9d\u8d1d\u4e2d\u6301\u7eed\u66f4\u65b0\u76f8\u5173\u7684\u7cfb\u5217\u6587\u7ae0\uff0c\u6b22\u8fce\u5927\u5bb6\u5173\u6ce8\u5e76\u79ef\u6781\u7559\u8a00\u5efa\u8bae\u3002\u4e0b\u9762\u5c31\u5148\u4e00\u8d77\u6765\u770b\u4e00\u4e0b\u672c\u7bc7\u6b63\u6587\u5185\u5bb9\u5427\uff0c\u5e0c\u671b\u80fd\u5e2e\u5230\u4f60\uff01<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.17golang.com\/uploads\/20241108\/1731076063672e1fdf0d1f1.jpg\" class=\"aligncenter\"><\/p>\n<p><strong>\u6570\u636e\u5e93\u64cd\u4f5c\u65f6\u7684\u5e38\u89c1\u9519\u8bef\uff1a\u672a\u6307\u5b9a\u6570\u636e\u5e93<\/strong><\/p>\n<p>\u5982\u95ee\u9898\u6240\u793a\uff0c\u7a0b\u5e8f\u5728\u6267\u884c sql \u67e5\u8be2\u65f6\u9047\u5230\uff1a&#8221;er_bad_db_error: unknown database&#8221; \u7684\u9519\u8bef\u3002\u8fd9\u662f\u56e0\u4e3a sql \u8bed\u53e5\u4e2d\u672a\u6307\u5b9a\u8981\u64cd\u4f5c\u7684\u6570\u636e\u5e93\uff0c\u5bfc\u81f4\u6570\u636e\u5e93\u65e0\u6cd5\u627e\u5230\u5bf9\u5e94\u7684\u8868\u3002<\/p>\n<p>\u5728 mysql \u4e2d\uff0c\u8981\u6307\u5b9a\u6570\u636e\u5e93\uff0c\u9700\u8981\u5728 sql \u8bed\u53e5\u7684\u5f00\u5934\u6dfb\u52a0 use \u6570\u636e\u5e93\u540d \u8bed\u53e5\u3002\u4f8b\u5982\uff0c<\/p>\n<pre>use my_db_01;<\/pre>\n<p>\u6267\u884c\u6b64\u8bed\u53e5\u540e\uff0c\u6240\u6709\u540e\u7eed\u7684 sql \u8bed\u53e5\u5c06\u9488\u5bf9\u6570\u636e\u5e93 my_db_01 \u6267\u884c\u3002<\/p>\n<p>\u5728\u4ee3\u7801\u4e2d\uff0c\u53ef\u4ee5\u5148\u4f7f\u7528 use \u8bed\u53e5\u6307\u5b9a\u6570\u636e\u5e93\uff0c\u7136\u540e\u6267\u884c sql \u67e5\u8be2\u3002\u4f8b\u5982\uff0c\u4fee\u6539\u540e\u7684\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n<pre>exports.regUser = (req, res) =&gt; {\n  \/\/ 1. \u83b7\u53d6\u7528\u6237\u4fe1\u606f\n  const userinfo = req.body;\n\n  \/\/ 2. \u6307\u5b9a\u6570\u636e\u5e93\n  db.query('USE my_db_01;');\n\n  \/\/ 3. \u6267\u884c\u6570\u636e\u5e93\u64cd\u4f5c\uff0c\u67e5\u91cd\u7528\u6237\u540d\n  \/\/ 4. \u5b9a\u4e49 SQL \u8bed\u53e5\n  const sql = 'SELECT * FROM getloonwh_users WHERE username=? AND usernumber=?';\n\n  \/\/ 5. \u6267\u884c\n  db.query(sql, [userinfo.username, userinfo.usernumber], (err, results) =&gt; {\n    if (err) return res.cc(err);\n    if (results.length &gt; 0) return res.send('\u5df2\u5b58\u5728\u7528\u6237\u540d\uff01\u91cd\u65b0\u8f93\u5165');\n\n    const sqlStr = 'INSERT INTO getloonwh_users SET ?';\n    db.query(sqlStr, { username: userinfo.username, usernumber: userinfo.usernumber }, (err, results) =&gt; {\n      if (err) return res.cc(err);\n      if (results.affectedRows !== 1) return res.cc('\u6ce8\u518c\u5931\u8d25\uff01');\n      res.send({ status: 0, msg: '\u6ce8\u518c\u6210\u529f\uff01' });\n    });\n  });\n\n  \/\/ res.send('\u6ce8\u518c\u6210\u529f\uff01')\n};<\/pre>\n<p>\u7ec8\u4e8e\u4ecb\u7ecd\u5b8c\u5566\uff01\u5c0f\u4f19\u4f34\u4eec\uff0c\u8fd9\u7bc7\u5173\u4e8e\u300a\u6570\u636e\u5e93\u62a5\u9519\u201cUnknown database\u201d\uff1a\u4e3a\u4ec0\u4e48\u6211\u7684SQL\u8bed\u53e5\u65e0\u6cd5\u627e\u5230\u76ee\u6807\u6570\u636e\u5e93\uff1f\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<dl>\n<dt>\n <\/dt>\n<\/dl>\n","protected":false},"excerpt":{"rendered":"<p>\u6570\u636e\u5e93\u62a5\u9519\u201cUnknown da&#46;&#46;&#46;<\/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-200580","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/200580","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=200580"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/200580\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=200580"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=200580"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=200580"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}