How to Eager Load Associations without duplication in NHibernate?

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Fetching Collections is a difficult operation. It has many side effects (as you realized, when there are fetched more collections). But even with fetching one collection, we are loading many duplicated rows.

In general, for collections loading, I would suggest to use the batch processing. This will execute more SQL queries… but not so much, and what is more important, you can do paging on the root list ARNomination.

See: 19.1.5. Using batch fetching you can find more details.

You have to mark your collections and/or entities with an attribute batch-szie="25".

xml:

<bag name="Contacts" ... batch-size="25">
...

fluent:

HasMany(x => x.Contacts)
  ...
  .BatchSize(25)

Please, check few arguments here:

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