How does DISTINCT work when using JPA and Hibernate

java jpa distinct
Steve Claridge picture Steve Claridge · Aug 28, 2009 · Viewed 160.9k times · Source

What column does DISTINCT work with in JPA and is it possible to change it?

Here's an example JPA query using DISTINCT:

select DISTINCT c from Customer c

Which doesn't make a lot of sense - what column is the distinct based on? Is it specified on the Entity as an annotation because I couldn't find one?

I would like to specify the column to make the distinction on, something like:

select DISTINCT(c.name) c from Customer c

I'm using MySQL and Hibernate.

Answer

Αλέκος picture Αλέκος · Oct 24, 2012

You are close.

select DISTINCT(c.name) from Customer c

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