Suppose you have a relation like the following, and you want to find all accounts that are under a given customer:
-
Customer 1
[list]
-
Account 1
-
Customer 2
[list] -
Account 2
-
Account 3
[*]Customer 3 -
Customer 4
[list] -
Account 4
-
Account 5
[/list][/list]
[/list]
(For Customer 1, it’s accounts 1, 2, 3, 4, and 5; for Customer 3, it’s accounts 4 and 5; etc.)
How would you do that?
This has come up a few times in my projects and I’m curious how others have solved it.
Here’s the gist of my solution:
public function getNestedRelated($nested, $from, $nestedCriteria = array(), $fromCriteria = array(), $maxLevels = false, $includeFirst = true, $_currentLevel = 0, &$_recursedSoFar = array())
{
// Always return an array (for array_merge)
$related = array();
// Prevent infinite recursion
if (in_array($this->primaryKey, $_recursedSoFar)) {
return $related;
}
$_recursedSoFar[] = $this->primaryKey;
// Nested records at this level
if ($_currentLevel > 0 || $includeFirst) {
// Whether to refresh nested records at this level. If criteria are
// provided, the db is queried anyway.
$refreshNested = false;
$related = $this->getRelated($nested, $refreshNested, $nestedCriteria);
}
// Handle singular ("HAS_ONE", "BELONGS_TO") relations
if (!is_array($related)) {
$related = array($related);
}
// Don't recurse past the max # of levels
if ($maxLevels !== false && $_currentLevel > $maxLevels) {
return $related;
}
// Whether to refresh children of this record. If criteria are provided,
// the db is queried anyway.
$refreshFrom = false;
// Go down one more level
$_currentLevel++;
foreach ($this->getRelated($from, $refreshFrom, $fromCriteria) as $child) {
// Recursive step
$nestedRelated = $child->getNestedRelated($nested, $from, $nestedCriteria, $fromCriteria, $maxLevels, $includeFirst, $_currentLevel, $_recursedSoFar);
$related = array_merge($related, $nestedRelated);
}
return $related;
}