Question

The code selects department, which then lists courses in that department, i then want the total amount of resources for linked courses (parent and child courses) to also be echoed.

I am trying to get a Total sum from foreach count in php array.
Can anbody help me with this please?

Here is my code:

$categoryid = $_POST['dept'];

//get course codes from department
$get_dept_codes = mysql_query("SELECT id, name FROM course_categories WHERE parent = 0 order by name asc");


    echo "<form method='POST' action='gsb_by_department.php'><p>";
    echo "<select size='1' name='dept'>";
    //loop through and list department names in drop down box
    while($row = mysql_fetch_array($get_dept_codes))
        {
        $catid = $row['id'];
        $catname = $row['name'];
        echo "<option name='category' value=$catid>$catname</option>";

        //echo $catid;
        //echo $catname;
        echo "<br />";
        }



echo "</select><input type='submit' value='Submit' name='submit'></p></form>";


//get course codes from department

$get_dept_codes = mysql_query("SELECT course.id, course.shortname, course.fullname, gsb_content.gsb
FROM _course INNER JOIN gsb_content ON course.id = gsb_content.courseid
WHERE (((course.category)=$categoryid)) AND course.metacourse = 0
ORDER BY course.id;");

//loop through and process for courses 

while($row = mysql_fetch_array($get_dept_codes))
    {

$childcourse = $row['id'];

//Get the $parentcourses

    $parentcourses= mysql_query("SELECT parent_course FROM course_meta where child_course = $childcourse"); 

//for each of the $parentcourses count FROM resource where course=$theparentcourse

    foreach($parentcourses as $parentcourse)) {
    $thenewid = $parentcourse['parent_course'];
    $thecount = mysql_query("SELECT count(*) FROM resource where course=$thenewid");
    }

//I want to be able to add up all the counts from the above and store in variable 

    $allcountstandardslinknum = array_sum($countstandardslinknum);
}

Does anybody have any ideas/guidance.
Would be greatly appreciated.

Answer 1

I’m not sure if the above was meant as pseudo code but the mysql_query method returns a result object so you need to do something like mysql_fetch_array.

As for getting the total you can just sum in your loop like so:

$total = 0;
foreach($parentcourse as $parentcourses)) {
    $thenewid = $parentcourse['parent_course'];
    $thecountrow = mysql_fetch_array(mysql_query("SELECT count(*) FROM resource where course=$thenewid"));
    $thecount = $thecountrow[0];
    $total += $thecount;
}
echo "Total is $total";

You may also want to add sanity checking and the like too.

Edit:
Also just noticed your foreach loop has the variables the wrong way, it should be:

foreach($parentcourses as $parentcourse){

I always remember this as a sentence: “for each of the items in $parentcourses name $parentcourse”

Edit2:
Your $parentcourses variable isn’t actually an array you need to grab each row in a similar way to your outer while loop something like:

$parentcoursesres= mysql_query("SELECT parent_course FROM course_meta where child_course = $childcourse"); 
$total = 0;
while($parentrow = mysql_fetch_assoc($parentcoursesres)){
    $thenewid = $parentrow['parent_course'];
    $thecountrow = mysql_fetch_array(mysql_query("SELECT count(*) FROM resource where course=$thenewid"));
    $thecount = $thecountrow[0];
    $total += $thecount;
}
echo "Total is $total";