select-PHP变量记录集与输出值

mysql_select_db($database_member, $member);
$dizhi= mysql_query("SELECT * FROM member WHERE username like '"+ $row_Recordset1['articles_author'] +"'");
$row = mysql_fetch_array($dizhi);
结果报错了
mysql_fetch_array(): supplied argument is not a valid MySQL result resource
求解决办法