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how to check if url already exists in database in PHP?
$url="http://dev.mysite.com/rahul/palake/?&test=1";
    $parse_url=parse_url($url);

    //first check if www is present in url or not
    if(!strstr($parse_url['host'],'www'))
    {
        $scheme=trim($parse_url['scheme']);

        //assign default scheme as http if scheme is not defined
        if( $scheme =='')
            $scheme='http';

        //create new url with 'www' embeded in it
        $url1=str_replace($scheme."://",$scheme."://www.",$url);

        //now $url1 should be like this http://www.mysite.com/rahul/palake/?&test=1

    }

    //so that $url && $url1 should be considered as one and the same
    //i.e. mysite.com/rahul/palake/?&test=1  is equivalent to  www.mysite.com/rahul/palake/?&test=1
    //should also be equivalent to http://mysite.com/rahul/palake/?&test=1

    //code to check url already exists in database goes here

    //here I will be checking if table.url like $url or table.url like $url1
    //if record found then return msg as url already exists