Inputting/overwriting information in arrays with PHP - php

Question

I have a small PHP page which takes data from MySQL and displays it via PHP in a monthly calendar. I'm having trouble arranging the data properly within an array to get the desired output.
First, I will describe what I would like to happen:
students come to classes on regular days of the week
they can also make or cancel reservations
the calendar also displays days when the school is not open
In order to display this data on the calendar, I use MySQL to output data from a variety of sources, and then input that into an array with PHP, which I sort by date and output.
My issue is, I would like to be able to handle more than one row of data per day, but because I am using the date as the key, I am limited on only displaying one result per day. If I use a loop to append the date with a counter in the key, I get overlapping results in situations where someone made a reservation and then cancelled that reservation on the same day.
As for my code...
First, I check to see if the student is registered in a weekly class, then input that class into the array.
$sql = "SELECT StudentDB.studentid, ClassDB.classID, ClassDB.class_level, ClassDB.class_title, ClassDB.time, ClassDB.teacher, StudentDB.first_name, StudentDB.last_name, StudentDB.payment_amount, ClassDB.day
FROM ClassDB
INNER JOIN RegDB ON ClassDB.classID = RegDB.classid
INNER JOIN StudentDB ON StudentDB.studentID = RegDB.studentid
WHERE StudentDB.studentid = '$studentid'";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
while($row = $result->fetch_assoc()) { // DISPLAY REGULAR CLASS DATA
$dayofclass = $row['day'];
$class_level = $row['class_level'];
$class_title = $row["class_title"];
$day = $row["day"];
$class_time = $row["class_time"];
$time = $row["time"];
// check which dates match the days of the week and store in an array
for ($i=1;$i<=$n;$i++){
if ($i<10) {
$i = "0" . $i;
}
$day=date("l",strtotime($yearmonth.$i)); //find weekdays
if($day==$dayofclass){
$time = date("H:i",strtotime($row['time']));
$dates[]=$yearmonth.$i;
$datesdata[$yearmonth.$i] = "0";
$timedata[$yearmonth.$i] = $time;
$classiddate[$yearmonth.$i] = $row['classID'];
}
}
}
echo "</table>";
$conn->close();
}
After that, I check for specific reservations (cancelations, irregular reservations, waitlists) and input them into the array:
$lowerlimit = $yearmonth . "01";
$upperlimit = $yearmonth . "31";
$sql = "SELECT AttendanceDB.*, ClassDB.*
FROM StudentDB
INNER JOIN AttendanceDB ON StudentDB.studentid = AttendanceDB.studentid
INNER JOIN ClassDB ON AttendanceDB.classid = ClassDB.classID
WHERE StudentDB.studentid = '$studentid'
AND AttendanceDB.class_time >= '$lowerlimit'
AND AttendanceDB.class_time <= '$upperlimit'";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
$loopcount = 0;
// store furikae data in the array
while($row = $result->fetch_assoc()) {
$phpdate = strtotime( $row["class_time"] );
$time = date("H:i",strtotime($row['time']));
$mysqldate = date( 'Y-m-d', $phpdate );
$loopcount++;
$mysqldate = $mysqldate . "+" . $loopcount;
// $loopcount++;
// $mysqldate = $mysqldate . "+" . $loopcount;
$previousdate = $mysqldate;
$previousfurikae = $row['furikae'];
if ($row["furikae"] == 3){
$dates[]=$mysqldate;
$datesdata[$mysqldate] = "1";
$timedata[$mysqldate] = $time;
$classiddate[$mysqldate] = $row['classID'];
} elseif ($row["furikae"] == 8 OR $row["furikae"] == 7) {
$dates[]=$mysqldate;
$datesdata[$mysqldate] = "3";
$timedata[$mysqldate] = $time;
} elseif ($row["furikae"] == 2) {
$dates[]=$mysqldate;
$datesdata[$mysqldate] = "2";
$timedata[$mysqldate] = $time;
}
}
}
$conn->close();
Then finally I check the school calendar and input the days off into the array:
$sql = "SELECT *
FROM SchoolScheduleDB
WHERE date >= '$lowerlimit'
AND date <= '$upperlimit'";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
// store furikae data in the array
while($row = $result->fetch_assoc()) {
$phpdate = strtotime( $row["date"] );
// $time = date("H:i",strtotime($row['time']));
// $mysqldate = date( 'Y-m-d', $phpdate ) . " " . $time;
$mysqldate = date( 'Y-m-d', $phpdate );
$dates[]=$mysqldate;
$datesdata[$mysqldate] = "666";
}
}
$conn->close();
The way I intended it to work was that:
First the regular classes would be input
Then any reservations would overwrite the original plans
And finally the school calendar would overwrite everything
Currently, this functions as it should, but it is limited to displaying 1 result per day, but I would like to be able to display more than 1 result per day for students who come to multiple classes.
Thank you for your help. If I made any mistakes in my question or my question is unclear I will do my best to revise it.

Answer 1

You can make a Sub-Array for each date by using edged brackets:
$data[20180528][] = 'aa';
$data[20180528][] = 'bb';
$data[20180529][] = 'cc';
$data[20180529][] = 'dd';
$data[20180529][] = 'ee';
will give you an Array like this:
20180528 => aa
=> bb
20180529 => cc
=> dd
=> ee