I want the query not to return any values. I can't just not query database, so I'd like to add some unreachable condition to predicates, something like 'where 1 <> 1'. But the CriteriaBuilder.equal() doesn't allow to do that. Is there any way to reach the goal?
Thanks.
How about
CriteriaBuilder.notEqual(CriteriaBuilder.literal(1), 1)
Although, if you know that this shouldn't execute, then using expressions might not be optimal on some RDBMS, if the database can't peek at bind values. I don't know how to do create a JPA Predicate with an inlined 1 <> 1
SQL expression, though...
Javadoc from CriteriaBuilder: "Create a disjunction (with zero disjuncts). A disjunction with zero disjuncts is false."
CriteriaBuilder cb..
Predicate itsFalse = cb.disjunction();
And then generated SQL depends about implementation, Hibernate produces 0=1. Why I prefer this method over other alternatives, is:
这个怎么样:
CriteriaBuilder.isTrue(CriteriaBuilder.literal(Boolean.FALSE));
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