PHP and or mysql: Make a date from some variables
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Assume that i have two variables in php:

    $year
    $month
Then I want to make another variable:

    $date
which:

    $date=$year-$month-25
So, if I have 2012 in $year and 7 for $month, $date will be 2012-07-25.

Actually, I will compare it with some date in MySQL.
$year and $month are inputted by user.

anybody have a solution?
The solution either how to make $date or anything as long it can be comparred with a date in mysql.
Thanks before. ^^