JPQL join, diference between selects

题

I have 3 Table A, B, C related with Many-To-One

is there difference between these two?

"SELECT a FROM A a "
    + "INNER JOIN a.b b "
    + "INNER JOIN b.c "

"SELECT c.b.a FROM C c "

I have tested both, and both work how I want. However, is there any real difference?

解决方案

The second query is invalid in the associations really are ManyToMany.

If they are ManyToOne or OneToOne, then the two queries are valid and equivalent.

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