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                        /PHP与MySQL关系大揭秘

一些文件出现错误怎么办

Warning: mysql_connect(): Access denied for user 'root'@'localhost' (using password: YES) inF:\xampp\htdocs\article\connect.php on line 4
Access denied for user 'root'@'localhost' (using password: YES)Access denied for user ''@'localhost' to database 'info'
Notice: Undefined index: id in F:\xampp\htdocs\article\article.show.php on line 3
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出现这个错误怎么办？