Conditionally adding to Doctrine WHERE clause - php

Question

How should one conditionally add constraints to the WHERE clause? For instance, if sex, maxAge, and minAge is provided, the WHERE clause should be WHERE sex=? AND maxAge<? AND minAge>?, but if maxAge is not provided, it should be WHERE sex=? AND minAge>? The logic below might work to determine whether where() or andWhere() is used, however, surely shouldn't be used.
<?php
// $qb instanceof QueryBuilder
$qb->select('u')
->from('User', 'u');
if(isset($param['sex'])) {
$qb->where('u.sex = ?1')->setParameter(1, $param['sex']);
}
if(isset($param['maxAge'])) {
if(isset($param['sex'])) {
$qb->andWhere('u.age < ?2')->setParameter(2, $param['maxAge']);
}
else {
$qb->where('u.age < ?2')->setParameter(2, $param['maxAge']);
}
}
if(isset($param['minAge'])) {
if(isset($param['sex'])|| isset($param['maxAge'])) {
$qb->andWhere('u.age > ?3')->setParameter(3, $param['minAge']);
}
else {
$qb->where('u.age > ?3')->setParameter(3, $param['minAge']);
}
}

Answer 1

There's no need for all those conditional checks. Just use andWhere everywhere.
<?php
// $qb instanceof QueryBuilder
$qb->select('u')
->from('User', 'u');
if(isset($param['sex'])) {
$qb->andWhere('u.sex = :sex')->setParameter('sex', $param['sex']);
}
if(isset($param['maxAge'])) {
$qb->andWhere('u.age < :maxAge')->setParameter('maxAge', $param['maxAge']);
}
if(isset($param['minAge'])) {
$qb->andWhere('u.age > :minAge')->setParameter('minAge', $param['minAge']);
}

Answer 2

I suppose you can create a single string for where:
$whereArr = $whereParams = [];
foreach (['sex' => 'u.sex = :sex', 'maxAge' => 'u.age < :maxAge', 'minAge' => 'u.age > :minAge'] as $key => $clause) {
if (isset($params[$key])) {
$whereArr[] = $clause;
$whereParams[':' . $key] = $params[$key];
}
}
if ($whereArr) {
$qb->where(implode(' and ', $whereArr))->setParameters($whereParams);
}

Answer 3

I'll probably go with ehymel's answer, but the following should work.
<?php
// $qb instanceof QueryBuilder
$qb->select('u')
->from('User', 'u');
$where = [];
if(isset($param['sex'])) {
$where[] = $qb->expr()->eq('sex', ':sex');
}
if(isset($param['maxAge'])) {
$where[] = $qb->expr()->lte('maxAge', ':maxAge');
}
if(isset($param['minAge'])) {
$where[] = $qb->expr()->gte('minAge', ':minAge');
}
if($where) {
$params=array_intersect_key($params, array_flip('sex','minAge','maxAge'));
$qb->add('where', $qb->expr()->andX(...$where))->setParameters($params);;
}