如何与教条和标准相结合

I want to create a rather complex and flexible query with Doctrines Criteria. I have an andWhere that is included in every query, but then (depending on input) I want to add some optinal parameters with orWhere.

$criteria = Criteria::create();

/* Add Criteria for last 55 Days (every query) */
$criteria->where(Criteria::expr()->gte('gameCreation', $long));

/* Gather optional Params */
$orxList = array();

/* Optional Criteria */
if (!empty($champions)) {
    foreach ($champions as $c) {
        $orxList[] = Criteria::expr()->eq('champion',$c);
    }
}

...
$criteria->andWhere(Criteria::expr()->orX($orxList));

This leads to an Exception:

No expression given to CompositeExpression.

How would I combine such a Criteria with the initial where clause?

You should use orX() from Expr class for this, example:

$orX = $exp->orX();
$index = 0;

foreach ($champions as $c) {
    $paramName = ':param_' . $index;
    $orX->add($qb->expr()->eq('u.column', $paramName));
    $qb->setParameter($paramName, $c);

    $index++;
}

However, if your array are just plain strings/object compared in the same way, consider using WHERE IN [] expression.

I faced a similar problem and solved it like this:

use Doctrine\Common\Collections\Expr\CompositeExpression;
...

/* Gather optional Params */
$orxList = array();

/* Optional Criteria */
if (!empty($champions)) {
    foreach ($champions as $c) {
        $orxList[] = Criteria::expr()->eq('champion', $c);
    }
}

...
$criteria->andWhere(new CompositeExpression(CompositeExpression::TYPE_OR, $orxList));

As you see the constructor of CompositeExpression accepts an array of expressions and this generates the correct query.