{"id":149,"date":"2020-05-13T01:21:45","date_gmt":"2020-05-12T17:21:45","guid":{"rendered":"http:\/\/www.wumingweb.com\/?p=149"},"modified":"2020-07-12T18:26:28","modified_gmt":"2020-07-12T10:26:28","slug":"149","status":"publish","type":"post","link":"http:\/\/www.wumingweb.com\/?p=149","title":{"rendered":"\u8303\u5f0f"},"content":{"rendered":"\n<p>\u6570\u636e\u5e93\u4e2d\u7684\u8303\u5f0f\uff1a\u5206\u4e3a\uff0c1NF,2NF,3NF,BCNF,4NF\u3002\u4e00\u822c\u6211\u4eec\uff0c\u6211\u4eec\u8bbe\u8ba1\u6570\u636e\u5e93\u5230\u7b2c\u4e09\u8303\u5f0f\u5c31\u7b97\u5b8c\u6574\u7684\u4e86\u3002\u5b83\u4eec\u7684\u5173\u7cfb\u5982\u4e0b\uff1a<\/p>\n\n\n\n<p style=\"color:#fc0404\" class=\"has-text-color\"><strong>\u7b2c\u4e00\u8303\u5f0f<\/strong>\uff1a\u5b9a\u4e49\u5f88\u591a\uff0c\u5176\u5b9e\u8bf4\u7684\u5c31\u662f\u5217\u4e0d\u53ef\u5206\u3002<\/p>\n\n\n\n<p>\u5982\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" width=\"1024\" height=\"93\" src=\"http:\/\/www.wumingweb.com\/wp-content\/uploads\/2020\/05\/image-1024x93.png\" alt=\"\" class=\"wp-image-150\" srcset=\"http:\/\/www.wumingweb.com\/wp-content\/uploads\/2020\/05\/image-1024x93.png 1024w, http:\/\/www.wumingweb.com\/wp-content\/uploads\/2020\/05\/image-300x27.png 300w, http:\/\/www.wumingweb.com\/wp-content\/uploads\/2020\/05\/image-768x70.png 768w, http:\/\/www.wumingweb.com\/wp-content\/uploads\/2020\/05\/image.png 1206w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p>\u5728\u5173\u7cfb\u6570\u636e\u5e93\u4e2d\u4e0d\u80fd\u51fa\u73b0\u8fd9\u79cd\u60c5\u51b5\u3002<\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p style=\"color:#fc0404\" class=\"has-text-color\"><strong>\u7b2c\u4e8c\u8303\u5f0f\u5b9a\u4e49<\/strong>\uff1a\u82e5R\u22081NF\uff0c\u4e14\u6bcf\u4e00\u4e2a\u975e\u4e3b\u5c5e\u6027\u5b8c\u5168\u51fd\u6570\u4f9d\u8d56\u4e8e\u7801\uff0c\u5219R\u22082NF\u3002\u610f\u601d\u662f\u975e\u4e3b\u5c5e\u6027\u5b8c\u5168\u4f9d\u8d56\u4e8e\u7801\uff08\u5019\u9009\u7801\uff0c\u4e3b\u7801\uff09\uff0c\u8fd9\u91cc\u9700\u8981\u6ce8\u610f\u4e00\u4e0b\uff0c\u662f\u975e\u4e3b\u5c5e\u6027\uff08\u5019\u9009\u7801\u4e4b\u5916\u7684\u5c5e\u6027\uff09\uff0c\u5728\u524d\u4e00\u7bc7\u6587\u7ae0\u5df2\u7ecf\u8bf4\u8fc7\u3002<\/p>\n\n\n\n<p>\u5982\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" width=\"1024\" height=\"156\" src=\"http:\/\/www.wumingweb.com\/wp-content\/uploads\/2020\/05\/image-1-1024x156.png\" alt=\"\" class=\"wp-image-151\" srcset=\"http:\/\/www.wumingweb.com\/wp-content\/uploads\/2020\/05\/image-1-1024x156.png 1024w, http:\/\/www.wumingweb.com\/wp-content\/uploads\/2020\/05\/image-1-300x46.png 300w, http:\/\/www.wumingweb.com\/wp-content\/uploads\/2020\/05\/image-1-768x117.png 768w, http:\/\/www.wumingweb.com\/wp-content\/uploads\/2020\/05\/image-1.png 1211w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p>(\u5b66\u53f7, \u7cfb\u540d, \u8bfe\u7a0b\u53f7, \u6210\u7ee9) \u22081NF<br> (\u5b66\u53f7, \u7cfb\u540d, \u8bfe\u7a0b\u53f7, \u6210\u7ee9)\u4e0d\u5c5e\u4e8e 2NF<br> \u5728\u8be5\u5173\u7cfb\u6a21\u5f0f\u4e2d\uff0c\u5b66\u53f7+\u8bfe\u7a0b\u53f7\u662f\u7801\uff0c\u5176\u4ed6\u5c5e\u6027\u90fd\u662f\u975e\u4e3b\u5c5e\u6027\uff0c\u4f46\u662f\u53ea\u6709\u6210\u7ee9\u5b8c\u5168\u4f9d\u8d56\u4e8e\u7801\uff0c\u7cfb\u540d\u662f\u90e8\u5206\u4f9d\u8d56\uff0c\u56e0\u4e3a\u5b66\u53f7\u5c31\u53ef\u4ee5\u63a8\u51fa\u5b66\u751f\u6240\u5728\u7684\u7cfb\u4e86\u3002<\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><\/p>\n\n\n\n<p style=\"color:#fc0404\" class=\"has-text-color\"><strong>\u7b2c\u4e09\u8303\u5f0f\u5b9a\u4e49<\/strong>\uff1a\u5b83\u7684\u5b9a\u4e49\u3002\u3002\u4e0d\u6253\u4e86\uff0c\u592a\u70e6\u4e86\u3002\u5176\u5b9e\u8bf4\u7684\u5c31\u662f\u6d88\u9664&nbsp;\u4f20\u9012\u4f9d<\/p>\n\n\n\n<p>\u8d56\u3002\u6bcf\u4e00\u4e2a\u975e\u4e3b\u5c5e\u6027\u90fd\u8981\u76f4\u63a5\u4f9d\u8d56\u4e8e\u7801\uff0c\u4e0d\u80fd\u4f20\u9012\u4f9d\u8d56\u4e8e\u7801\u3002\u5982\uff1a\u5728\u4e00\u4e2a<\/p>\n\n\n\n<p>\u5b66\u751f\u8868\u4e2d\uff0c\u6211\u4eec\u89c4\u5b9a\u4e00\u4e2a\u7cfb\u7684\u5b66\u751f\u662f\u4f4f\u5728\u540c\u4e00\u4e2a\u5bbf\u820d\u533a\u57df\u7684\uff0c\u4e8e\u662f\uff0c\u8be5\u5173<\/p>\n\n\n\n<p>\u7cfb\u6a21\u578b\u4e3a\uff1a<\/p>\n\n\n\n<p>\u5b66\u751f\u8868(\u5b66\u53f7,&nbsp;\u7cfb\u540d,&nbsp;\u5bbf\u820d\u533a)<\/p>\n\n\n\n<p>\u5728\u8fd9\u5173\u7cfb\u4e2d\uff0c\u5b66\u53f7\u4e3a\u7801\uff0c\u5b66\u53f7\u2014\u2014&gt;\u7cfb\u540d\uff0c\u5b66\u53f7\u2014\u2014&gt;\u5bbf\u820d\u533a\uff0c\u4f46\u662f\uff0c\u7cfb\u540d\u4e5f\u80fd\u63a8\u51fa\u5bbf\u820d\u533a\uff0c\u53d8\u6210&nbsp; 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