Why is this query not working?
$query = ("SELECT * FROM
(SELECT *, (
(((endingLatitude - " . $h . ")(endingLatitude - " . $h . "))
/" . pow($r1, 2) . ")
+
((endingLongitude - " . $k . ")(endingLongitude - " . $k . "))
/" . pow($r2, 2) . "
) AS point2
FROM (SELECT *, ((
(
((startingLatitude - " . $h . ")(startingLatitude - " . $h . "))
/" . pow($r1, 2) . ")
+
((startingLongitude - " . $k . ")(startingLongitude - " . $k . "))
/" . pow($r2, 2) . "))
AS point1
FROM (SELECT * FROM trips WHERE distance >='" . ($distance * .25) . "') as query1)
as query2) as query3 WHERE point1 <= 1 AND point2 <= 1 LIMIT 0 , 10;");
$result = mysqli_query($con, $query);
$h and $k is the ellipses x and y coordinates respectively. I am using a formula found here to calculate whether or not the two points, (startingLat,startingLong) and (endingLat,endingLong) are within an ellipse with vertical height $r1 and horizontal height $r2. I am also limiting the rows that I search to rows that have a distance cell value of greater than $distance * .25.
I think it might have something to do with a parenthesis error or something to do with the way I am sub querying/performing my calculations.
Using
die(mysqli_error($con));
returns an error of You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '(endingLatitude - 36.9564753)) /796.842964388) + ((endingLongitud' at line 3
I believe you have to use Mysql multiplication arithmetic operator, *. https://dev.mysql.com/doc/refman/5.0/en/arithmetic-functions.html#operator_times
Instead of:
(endingLatitude - " . $h . ")(endingLatitude - " . $h . ")
Do this...
(endingLatitude - " . $h . ") * (endingLatitude - " . $h . ")