Question

I am making a meeting room booking system in which there should be no times within the start and end dates so in theory the validation should check for no dates/times within one start and end date time frame.

I have two tables, I can insert into it fine with both start and end dates so the only columns i am interested in at the moment are these

meetingrooms

|————————————|
|- bookingtime -|-bookingend-|

I understand the principle behind the sanity check and the check i can do in psudocode. Here is the code i have got so far –
>

p4a_db::singleton()->query("INSERT INTO meetingrooms(location_id, bookingtime, bookingend, merono_id)
                WHERE bookingtime < " . $date . " AND bookingend > " . $date . "
                OR
                bookingdate < " . $date . " AND bookingend > " . $dateend . "
                VALUES(?,?,?,?)",
                array($location, $date, $dateend, $merono));

I don’t want to insert data directly into the statement but until i understand how to do this i am stuck, so the question,

How do i perform a sanity check before the data is inserted so that i don’t get dates within booked times.

any help would be greatly appreciated.

Answer 1

after a long and intensive search, I have now got a working example of this method, along with a method of protecting against sql injection, here’s the code;

if ($this->BookingValue == 1)
    {
        $sql = "SELECT COUNT(*) as num FROM meeting_room_bookings
                WHERE
                (
                (? < start_at AND ? > start_at)
                OR
                (? > start_at AND ? < end_at)
                )
                AND
                meeting_room_id = ?";

        $result = p4a_db::singleton()->fetchRow($sql, array($date, $date, $date, $dateend, $merono));

        if ( 0 == $result["num"] )
        {

         p4a_db::singleton()->query("INSERT INTO meeting_room_bookings (start_at, end_at, meeting_room_id)
                    VALUES
                    (?,?,?)", array($date, $dateend, $merono));

            return true;
        }       
        else
        {
         return false;

There isn’t much to explain about this code, but in term of differences, (excluding the change in column names with the table) the query is now prepared before the value is set, then it is possible to use it in an if statement, thus allowing the validation to take place to filter results between different dates.

along with this i have added validation to stop dates from other meeting rooms being included within the statement via the AND statement where the meeting room id is limeted to a single value.

Although now, which will lead on to a separate question is another thrown error that comes from this statement, i know the insert is sound but something from this prepared statement causes the error:

SQLSTATE[HY093]: Invalid parameter number: number of bound variables does not match number of tokens
File: Pdo.php, Line: 234

Although now i am looking into a error that is thrown from the prepared statement and will update this answer when there is a fix, thanks for the help.