Checking How Many Values in an Array are Greater than x

Question

Having created an array of values using a MySQL query, I need to check if they are all at least equal to a given value. This is for checking room availability in a hotel.

First I do the the MySQL query:

foreach( $datearray as $value ) {
$query_avail = "SELECT cupo, ex_cupo.room_id FROM ex_cupo JOIN ex_rooms ON ex_cupo.room_id=ex_rooms.room_id  AND ex_rooms.room_id = '$room_id' AND dt = '$value'";
$avail = mysql_query($query_avail, $MySQL_extranet) or die(mysql_error());
$row_avail = mysql_fetch_assoc($avail);
   $availresult[] = $row_avail['cupo'];
}

"Cupo" is the number of rooms available for a given date, so $availresult will be an array of the number of rooms available across a range of dates.

Now if someone wants to book (say) 2 rooms for those dates, I need to ensure that each value in the array is at least 2. For example, if there are 5 dates in the range and they are 2, 2, 1, 2, 2, I need to return false, but if they are 2, 2, 2, 2, 2 or 2, 2, 3, 2, 2, I need to return true.

How do I do that? (I hope I explained it well enough.)

Obviously the choice of 2 is just an example. It will normally be a variable called $numrooms.

Answer 1

Add a WHERE cupo > 2 to your SQL code. Have the database give you only the results you want, rather than walking through the results to check that cupo>2 yourself.

If you need to be able to change it, use a parametrized query. See http://php.net/manual/en/security.database.sql-injection.php for details.

Answer 2

$testArray = array(2,2,2,2,1,2);

$valid = array_reduce(
    $testArray,
    function ($match, $value) {
        return $match && ($value >= 2);
    },
    TRUE
);
var_dump($valid);

EDIT

How to pass $numrooms through:

$testArray = array(2,2,2,2,1,2);
$numrooms = 2;

$valid = array_reduce(
    $testArray,
    function ($match, $value) use ($numrooms) {
        return $match && ($value >= $numrooms);
    },
    TRUE
);
var_dump($valid);

Answer 3

you should pass the number of rooms to your sql statement as a condition such as:

$query_avail = "SELECT cupo, ex_cupo.room_id FROM ex_cupo
  JOIN ex_rooms ON   ex_cupo.room_id=ex_rooms.room_id  AND
    ex_rooms.room_id = '$room_id' AND dt = '$value' WHERE cupo > 1";

as the number one could be your PHP passed value.

Answer 4

If you can do this at the SQL level (as Andy suggested), that would be the best option . However, if you need to do this in PHP, you could easily iterate over your array, and set a flag to false if any value is below your minimum amount allowed:

$minimum_val = 2;
$enough_rooms = true;
foreach($availresult as $item) {
  if ($item < $minimum_val) {
    $enough_rooms = false;
  }
}

Answer 5

Thanks to everyone who answered. I think I have my solution now, and I'm pressing ahead. Happy Christmas, All.