JPA / JPQL返回不完整的结果，其中xy IS NULL或xyz = 1

Question

I have the following SQL returning 13 results

SELECT *
FROM AAA a
JOIN BBB b ON b.id = a.b_id
LEFT JOIN CCC c ON c.id = b.c_id
LEFT JOIN DDD d ON d.id = c.d_id
WHERE b.c_id IS NULL
OR d.status = 1

And following JPQL returning 3 results

SELECT a
FROM AAA a
WHERE a.b.c IS NULL

And following JPQL returning 10 results

SELECT a
FROM AAA a
WHERE a.b.c.d.status = 1

But the following JPQL returns 10 results, missing the 3 null ones.

SELECT a
FROM AAA a
WHERE a.b.c IS NULL
OR a.b.c.d.status = 1

What am I missing? Where do I begin debugging this?

Answer 1

Where do I begin debugging this?

If you're uncertain about your ORM, tune the log level so you could see the generated SQL queries or directly check database logs.

What am I missing?

Condition WHERE abcdstatus = 1 forces jpa provider to create inner joins for all tables in the path (BBB, CCC, DDD). This neutralizes OR condition abc IS NULL .