Optimize SELECT DISTINCT Via Hibernate HINT_PASS_DISTINCT_THROUGH Hint
Description: Starting with Hibernate 5.2.2, we can optimize JPQL (HQL) query entites of type SELECT DISTINCT via HINT_PASS_DISTINCT_THROUGH hint. Keep in mind that this hint is useful only for JPQL (HQL) JOIN FETCH-ing queries. Is not useful for scalar queries (e.g., List<Integer>), DTO or HHH-13280. In such cases, the DISTINCT JPQL keyword is needed to be passed to the underlying SQL query. This will instruct the database to remove duplicates from the result set.
Key points:
- use
@QueryHints(value = @QueryHint(name = HINT_PASS_DISTINCT_THROUGH, value = "false"))
Output example:
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