cannot create a select query through Database object
i got a Database class from http://net.tutsplus.com/tutorials/php/real-world-oop-with-php-and-mysql/ .but after applying that class to my code and after hosting that code i am unable to make select query in my server.it is returned empty array always.but if i make the DB object in the same database file ..it works clearly :: i don't know what is the reason: does any one can help me .Really i'm in a mess.   
    thankz;
cannot create a select query through Database object
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i got a Database class from http://net.tutsplus.com/tutorials/php/real-world-oop-with-php-and-mysql/ .but after applying that class to my code and after hosting that code i am unable to make select query in my server.it is returned empty array always.but if i make the DB object in the same database file ..it works clearly :: i don't know what is the reason: does any one can help me .Really i'm in a mess.   
    thankz;