Question

In requests to my application i often get ids of the objects, which should be associated. However I have to perform a check to see if they are.

Example scenario:
Class A and B are associated:

A {
    static hasMany = [bs: B]
}

In my request I will get aid and bid.
What I usually do is:

def a = A.get(aid)
def b = a.bs.find {it.id == bid}

What would be a better way to make this check? From performance point of view?

Thanks

Answer 1

If B has a belongsTo = [ a : A ] defined in it, then you can do this:

def a = A.get(aid)
def b = B.find("from B as b where b.id=:id and b.a = :a", [id:bid, a:a])
if (b) {
   // b exists -- do something with it here
} else {
   // uh oh! b isn't within a
}

This won’t do an iteration over all the sets elements like your code. Essentially, it’s the same as erturne’s solution, but this actually loads the object.