Working with output from joined tables with php oop - php

Question

As part of my learning OOP PHP, I have made a database object that includes the following method:
public static function find_by_sql($sql="") {
global $database;
$result_set = $database->query($sql);
$object_array = array();
while ($row = $database->fetch_array($result_set)) {
$object_array[] = static::instantiate($row);
}
return $object_array;
}
and I can use this to retrieve and access data from a single table, however when I try to use it with joined tables, the object only gives me the data from the primary table e.g.
$sql = "SELECT s.name, m.id, m.firstName, m.lastName, m.dob";
$sql .= " FROM members AS m";
$sql .= " LEFT JOIN mbr_sections AS ms ON m.id = ms.member_id";
$sql .= " LEFT JOIN sections AS s ON ms.section_id = s.id";
$sql .= " ORDER BY s.organisation ASC, s.name ASC, m.lastName ASC, m.firstName ASC";
$sql .= " LIMIT {$per_page} ";
$sql .= " OFFSET {$pagination->offset()}";
$members = Member::find_by_sql($sql);
Using the above query the following code outputs nothing for the s.name field, but all the fields from the members table are correctly listed. I know that the MySQL query is accessing the data, as the ORDER BY statement is correctly sorting the output.
<?php foreach($members as $member): ?>
<tr>
<td><?php echo $member->name;?></td>
<td><?php echo $member->full_name();?></td>
<td><?php echo $member->getAge($member->dob);?></td>
<td>Edit</td>
<td>Delete</td>
</tr>
<?php endforeach; ?>
If I output $members with print_r($members) it only contains the data from the members table, how do I access the data retrieved from the other tables?
Thanks

Answer 1

You need to select them too here:
$sql = "SELECT s.name, m.id, m.firstName, m.lastName, m.dob";
$sql .= " FROM members AS m";
$sql .= " LEFT JOIN mbr_sections AS ms ON m.id = ms.member_id";
$sql .= " LEFT JOIN sections AS s ON ms.section_id = s.id";
$sql .= " ORDER BY s.organisation ASC, s.name ASC, m.lastName ASC, m.firstName ASC";
$sql .= " LIMIT {$per_page} ";
$sql .= " OFFSET {$pagination->offset()}";
$members = Member::find_by_sql($sql);
You only selected name, id, firstName, lastName and dob.
Here is an example:
$sql = "SELECT s.name, m.id, m.firstName, m.lastName, m.dob, mbr_sections.field_you_want, sections.*";