Efficently loading deep object graphs
time to read 2 min | 334 words

Here is an interesting approach to get deep object graphs effectively.  This will ensure that you will get all the relevant collections without having to lazy load them and without a huge cartesian product. Especially useful if you want to load a collection of items with the associated deep object graph.

public Policy GetPolicyEagerly(int policyId)
{
	IList list = ActiveRecordUnitOfWorkFactory.CurrentSession.CreateMultiQuery()
		.Add(@"from Policy policy left join fetch policy.PolicyLeadAssociations
                                  where policy.Id = :policyId")
		.Add(@"from Policy policy left join fetch policy.PolicyEmployeeAssociations
                                  where policy.Id = :policyId")
		.Add(@"from Policy policy left join fetch policy.PolicyManagerAssociations
                                  where policy.Id = :policyId")
		.Add(@"from Policy policy left join fetch policy.PolicyDepartmentAssociations
                                  where policy.Id = :policyId")
		.Add(@"from Policy policy left join fetch policy.PolicyCustomerAssociations
                                  where policy.Id = :policyId")
		.SetEntity("policy", Policy)
		.List();
	IList firstResultList = (IList) list[0];
	if(firstResultList.Count==0)
		return null;
	return = (Policy) firstResultList [0];
}

The domain above is a fake one, by the way, don't try to make any sense of it.

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