Comparing two dates

programming
1

I need help comparing two dates.

Before I insert I want to check to make sure no event is overlapping another. Basically their cant be two events within the same time frame.

inserting a date of july 21st 2008 to july 25th 2008 will come into conflict if someone makes an event on july 24th 2008 to july 30th 2008.

Right now I have:


<?php
if(isset($_POST['add'])) {
	$begdate_m = $_POST['begdatem'];
	$begdate_d = $_POST['begdated'];
	$begdate_y = $_POST['begdatey'];
	$enddate_m = $_POST['enddatem'];
	$enddate_d = $_POST['enddated'];
	$enddate_y = $_POST['enddatey'];
	$startdate = $begdate_y."-".$begdate_m."-".$begdate_d;
	$enddate = $enddate_y."-".$enddate_m."-".$enddate_d;
	$startdate = strtotime($startdate);
	$enddate = strtotime($enddate);
	
	$add = true;
	$query = mysql_query("SELECT * FROM de_featuredevent") or die(mysql_error());
	while($row = mysql_fetch_array($query))
	{
		$sql = mysql_query("SELECT * FROM de_featuredevent WHERE '$startdate' OR '$enddate' BETWEEN '$row[start_date]' AND '$row[end_date]'") or die(mysql_error());
		echo "SELECT * FROM de_featuredevent WHERE '$startdate' OR '$enddate' BETWEEN '$row[start_date]' AND '$row[end_date]'";
		$num = mysql_num_rows($sql);
		if($num == 0)
		{
//If their is none found do this
			echo " = timing ok<br>";
		}
		else
		{
			echo " = time mismatch<br>";
			$add = false;
		}
	}
	if($add == false)
	{
		echo "not adding";
	}
	else
	{
		echo "adding";
	}
}
?>

I have two dates in the database right now:

Jan 2 - Jan 5
&
Jan 7 - Jan 10

If I try any date ie: Jan 15 - Jan 20 with all my echos above I get this:


SELECT * FROM de_featuredevent WHERE '1200373200' OR '1200805200' BETWEEN '1199250000' AND '1199509200' = time mismatch
SELECT * FROM de_featuredevent WHERE '1200373200' OR '1200805200' BETWEEN '1199941200' AND '1200373200' = time mismatch
not adding

Both of the integrers are not between any of those values…It makes no sense…

So my issue is with my $sql…I have to be doing something wrong here. My logic isnt right or something.

I am using the UNIX timestamp by the way.