{"id":78490,"date":"2024-10-16T11:59:00","date_gmt":"2024-10-16T03:59:00","guid":{"rendered":"https:\/\/server.hk\/cnblog\/78490\/"},"modified":"2024-10-16T11:59:00","modified_gmt":"2024-10-16T03:59:00","slug":"mysql%e6%8c%87%e4%bb%a4-float%ef%bc%88%e6%b5%ae%e9%bb%9e%e6%95%b8%ef%bc%89","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/78490\/","title":{"rendered":"MySQL\u6307\u4ee4: FLOAT\uff08\u6d6e\u9ede\u6578\uff09"},"content":{"rendered":"<h1 id=\"mysql%e6%8c%87%e4%bb%a4-float%ef%bc%88%e6%b5%ae%e9%bb%9e%e6%95%b8%ef%bc%89-sHOTXtgFNW\">MySQL\u6307\u4ee4: FLOAT\uff08\u6d6e\u9ede\u6578\uff09<\/h1>\n<p>\u5728\u8cc7\u6599\u5eab\u7ba1\u7406\u7cfb\u7d71\u4e2d\uff0c\u6578\u64da\u985e\u578b\u7684\u9078\u64c7\u5c0d\u65bc\u6578\u64da\u7684\u5b58\u5132\u548c\u8655\u7406\u81f3\u95dc\u91cd\u8981\u3002MySQL\u4f5c\u70ba\u4e00\u500b\u6d41\u884c\u7684\u958b\u6e90\u8cc7\u6599\u5eab\u7cfb\u7d71\uff0c\u63d0\u4f9b\u4e86\u591a\u7a2e\u6578\u64da\u985e\u578b\uff0c\u5176\u4e2d\u4e4b\u4e00\u5c31\u662fFLOAT\uff08\u6d6e\u9ede\u6578\uff09\u3002\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0eFLOAT\u6578\u64da\u985e\u578b\u7684\u7279\u6027\u3001\u4f7f\u7528\u5834\u666f\u53ca\u5176\u5728MySQL\u4e2d\u7684\u61c9\u7528\u3002<\/p>\n<h2 id=\"float%e6%95%b8%e6%93%9a%e9%a1%9e%e5%9e%8b%e6%a6%82%e8%bf%b0-sHOTXtgFNW\">FLOAT\u6578\u64da\u985e\u578b\u6982\u8ff0<\/h2>\n<p>FLOAT\u662f\u4e00\u7a2e\u7528\u65bc\u5b58\u5132\u6d6e\u9ede\u6578\u7684\u6578\u64da\u985e\u578b\uff0c\u9069\u5408\u7528\u65bc\u9700\u8981\u8868\u793a\u5c0f\u6578\u7684\u60c5\u6cc1\u3002\u5b83\u7684\u5b58\u5132\u65b9\u5f0f\u662f\u57fa\u65bc\u79d1\u5b78\u8a18\u6578\u6cd5\uff0c\u9019\u4f7f\u5f97\u5b83\u80fd\u5920\u8868\u793a\u975e\u5e38\u5927\u7684\u6216\u975e\u5e38\u5c0f\u7684\u6578\u5b57\u3002FLOAT\u6578\u64da\u985e\u578b\u7684\u7bc4\u570d\u901a\u5e38\u662f\u5f9e-3.402823466E+38\u52303.402823466E+38\uff0c\u7cbe\u5ea6\u7d04\u70ba7\u4f4d\u5341\u9032\u5236\u6578\u3002<\/p>\n<h2 id=\"float%e7%9a%84%e5%ae%9a%e7%be%a9%e8%88%87%e8%aa%9e%e6%b3%95-sHOTXtgFNW\">FLOAT\u7684\u5b9a\u7fa9\u8207\u8a9e\u6cd5<\/h2>\n<p>\u5728MySQL\u4e2d\uff0cFLOAT\u6578\u64da\u985e\u578b\u7684\u5b9a\u7fa9\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre><code>FLOAT[(M,D)]<\/code><\/pre>\n<ul>\n<li><strong>M<\/strong>: \u6574\u6578\u90e8\u5206\u7684\u6700\u5927\u4f4d\u6578\uff08\u53ef\u9078\uff09\u3002<\/li>\n<li><strong>D<\/strong>: \u5c0f\u6578\u90e8\u5206\u7684\u4f4d\u6578\uff08\u53ef\u9078\uff09\u3002<\/li>\n<\/ul>\n<p>\u4f8b\u5982\uff0c\u82e5\u8981\u5b9a\u7fa9\u4e00\u500bFLOAT\u985e\u578b\u7684\u6b04\u4f4d\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0bSQL\u8a9e\u53e5\uff1a<\/p>\n<pre><code>CREATE TABLE example (\n    id INT AUTO_INCREMENT PRIMARY KEY,\n    price FLOAT(7, 2)\n);<\/code><\/pre>\n<p>\u5728\u9019\u500b\u4f8b\u5b50\u4e2d\uff0cprice\u6b04\u4f4d\u53ef\u4ee5\u5b58\u5132\u6700\u591a7\u4f4d\u6578\u5b57\uff0c\u5176\u4e2d2\u4f4d\u662f\u5c0f\u6578\u3002<\/p>\n<h2 id=\"float%e8%88%87double%e7%9a%84%e5%8d%80%e5%88%a5-sHOTXtgFNW\">FLOAT\u8207DOUBLE\u7684\u5340\u5225<\/h2>\n<p>\u5728MySQL\u4e2d\uff0c\u9664\u4e86FLOAT\u4e4b\u5916\uff0c\u9084\u6709\u53e6\u4e00\u500b\u6d6e\u9ede\u6578\u985e\u578b\uff0c\u5373DOUBLE\u3002\u5b83\u5011\u4e4b\u9593\u7684\u4e3b\u8981\u5340\u5225\u5728\u65bc\u7cbe\u5ea6\u548c\u5b58\u5132\u5927\u5c0f\uff1a<\/p>\n<ul>\n<li><strong>FLOAT<\/strong>: \u901a\u5e38\u4f54\u75284\u500b\u5b57\u7bc0\uff0c\u7cbe\u5ea6\u7d04\u70ba7\u4f4d\u5341\u9032\u5236\u6578\u3002<\/li>\n<li><strong>DOUBLE<\/strong>: \u901a\u5e38\u4f54\u75288\u500b\u5b57\u7bc0\uff0c\u7cbe\u5ea6\u7d04\u70ba15\u4f4d\u5341\u9032\u5236\u6578\u3002<\/li>\n<\/ul>\n<p>\u56e0\u6b64\uff0c\u7576\u9700\u8981\u66f4\u9ad8\u7684\u7cbe\u5ea6\u6642\uff0c\u5efa\u8b70\u4f7f\u7528DOUBLE\uff0c\u800c\u5728\u5c0d\u5b58\u5132\u7a7a\u9593\u8981\u6c42\u8f03\u9ad8\u7684\u60c5\u6cc1\u4e0b\uff0c\u5247\u53ef\u4ee5\u9078\u64c7FLOAT\u3002<\/p>\n<h2 id=\"%e4%bd%bf%e7%94%a8float%e7%9a%84%e5%a0%b4%e6%99%af-sHOTXtgFNW\">\u4f7f\u7528FLOAT\u7684\u5834\u666f<\/h2>\n<p>FLOAT\u6578\u64da\u985e\u578b\u9069\u5408\u7528\u65bc\u4ee5\u4e0b\u5834\u666f\uff1a<\/p>\n<ul>\n<li>\u9700\u8981\u8868\u793a\u5c0f\u6578\u7684\u8ca1\u52d9\u6578\u64da\uff0c\u4f8b\u5982\u50f9\u683c\u3001\u5229\u7387\u7b49\u3002<\/li>\n<li>\u79d1\u5b78\u8a08\u7b97\u4e2d\u9700\u8981\u8868\u793a\u975e\u5e38\u5927\u6216\u975e\u5e38\u5c0f\u7684\u6578\u5b57\u3002<\/li>\n<li>\u5c0d\u65bc\u4e0d\u9700\u8981\u6975\u9ad8\u7cbe\u5ea6\u7684\u6578\u64da\u5b58\u5132\u3002<\/li>\n<\/ul>\n<h2 id=\"%e6%b3%a8%e6%84%8f%e4%ba%8b%e9%a0%85-sHOTXtgFNW\">\u6ce8\u610f\u4e8b\u9805<\/h2>\n<p>\u5118\u7ba1FLOAT\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\u975e\u5e38\u6709\u7528\uff0c\u4f46\u5728\u4f7f\u7528\u6642\u4e5f\u9700\u8981\u6ce8\u610f\u4ee5\u4e0b\u5e7e\u9ede\uff1a<\/p>\n<ul>\n<li>\u6d6e\u9ede\u6578\u7684\u8a08\u7b97\u53ef\u80fd\u6703\u5c0e\u81f4\u7cbe\u5ea6\u640d\u5931\uff0c\u56e0\u6b64\u5728\u9032\u884c\u8ca1\u52d9\u8a08\u7b97\u6642\uff0c\u5efa\u8b70\u4f7f\u7528DECIMAL\u985e\u578b\u4ee5\u907f\u514d\u8aa4\u5dee\u3002<\/li>\n<li>\u5728\u9032\u884c\u6bd4\u8f03\u64cd\u4f5c\u6642\uff0c\u61c9\u8a72\u5c0f\u5fc3\u6d6e\u9ede\u6578\u7684\u7cbe\u5ea6\u554f\u984c\uff0c\u907f\u514d\u51fa\u73fe\u610f\u5916\u7684\u6bd4\u8f03\u7d50\u679c\u3002<\/li>\n<\/ul>\n<h2 id=\"%e7%b5%90%e8%ab%96-sHOTXtgFNW\">\u7d50\u8ad6<\/h2>\n<p>FLOAT\u6578\u64da\u985e\u578b\u5728MySQL\u4e2d\u662f\u4e00\u500b\u9748\u6d3b\u4e14\u9ad8\u6548\u7684\u9078\u64c7\uff0c\u9069\u5408\u7528\u65bc\u9700\u8981\u8868\u793a\u5c0f\u6578\u7684\u5404\u7a2e\u61c9\u7528\u5834\u666f\u3002\u4e86\u89e3\u5176\u7279\u6027\u53ca\u4f7f\u7528\u65b9\u6cd5\uff0c\u53ef\u4ee5\u5e6b\u52a9\u958b\u767c\u8005\u66f4\u597d\u5730\u8a2d\u8a08\u548c\u7ba1\u7406\u8cc7\u6599\u5eab\u3002\u5c0d\u65bc\u9700\u8981\u9ad8\u6548\u80fd\u548c\u9748\u6d3b\u6027\u7684\u6578\u64da\u5b58\u5132\u89e3\u6c7a\u65b9\u6848\uff0c\u9078\u64c7\u5408\u9069\u7684\u6578\u64da\u985e\u578b\u81f3\u95dc\u91cd\u8981\u3002<\/p>\n<p>\u5982\u9700\u4e86\u89e3\u66f4\u591a\u95dc\u65bc<code>VPS<\/code>\u3001<code>\u9999\u6e2fvps<\/code>\u53ca<code>\u4e91\u670d\u52a1\u5668<\/code>\u7684\u8cc7\u8a0a\uff0c\u8acb\u8a2a\u554f\u6211\u5011\u7684\u7db2\u7ad9 <a href=\"https:\/\/server.hk\">Server.HK<\/a>\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3MySQL\u4e2d\u7684FLOAT\u6307\u4ee4\uff0c\u638c\u63e1\u6d6e\u9ede\u6578\u7684\u5b9a\u7fa9\u3001\u7528\u6cd5\u53ca\u5176\u5728\u6578\u64da\u5eab\u4e2d\u7684\u61c9\u7528\uff0c\u63d0\u5347\u6578\u64da\u8655\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-78490","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78490","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=78490"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78490\/revisions"}],"predecessor-version":[{"id":78491,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/78490\/revisions\/78491"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=78490"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=78490"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=78490"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}