# How to emulate LEFT JOIN FETCH using Record-based projections

DevFeed: [How to emulate LEFT JOIN FETCH using Record-based projections](<https://devfeed.tech/articles/how-to-emulate-left-join-fetch-using-record-based-projections-21983.md>)

Original publisher: [Read original article](<https://vladmihalcea.com/emulate-left-join-fetch-using-projections/>)

Author: vladmihalcea

Published: 2026-02-27T08:52:13Z

Content type: tutorial

Language: en

Sources: [Vlad Mihalcea](<https://devfeed.tech/sources/vlad-mihalcea.md>)

Topics: [Persistence](<https://devfeed.tech/topics/persistence.md>), [Java](<https://devfeed.tech/topics/java.md>), [Jakarta EE](<https://devfeed.tech/topics/jakarta-ee.md>)

Tags: [article](<https://devfeed.tech/tags/article.md>), [fetch](<https://devfeed.tech/tags/fetch.md>), [hibernate](<https://devfeed.tech/tags/hibernate.md>), [how-to](<https://devfeed.tech/tags/how-to.md>), [jakarta-ee](<https://devfeed.tech/tags/jakarta-ee.md>), [java](<https://devfeed.tech/tags/java.md>), [join-fetch](<https://devfeed.tech/tags/join-fetch.md>), [jpa](<https://devfeed.tech/tags/jpa.md>), [unrelated](<https://devfeed.tech/tags/unrelated.md>)

## AI overview

This tutorial explains how to emulate a LEFT JOIN FETCH between two root entities without fetching an intermediate child entity. It uses record-based projections and a JPQL query, and describes how the resulting entities remain managed in the persistence context and can produce updates during flush.

## Source excerpt

Introduction In this article, I'm going to show you how to emulate a LEFT JOIN FETCH between two root entities without fetching the intermediate child entity. I got the inspiration for this article by this comment thread on my blog. Domain Model Let's assume we have the following entities: The Post is the root entity of our hierarchy, but just like it's the case with the relational model, the root entity does not have any reference to its children: On the second level of our hierarchy we have the PostDetails: The PostDetails... Read More The post How to emulate LEFT JOIN FETCH using Record-based projections appeared first on Vlad Mihalcea.