Hibernate Criteria Query - nested condition

问题

I can't figure out how to create a query like this with Hibernate Criteria synthax

select * from x where x.a = 'abc'  and (x.b = 'def' or x.b = 'ghi')

Do you have an idea of how to do that?
I'm Using Hibernate Restriction static methods but I don't understand how to specify the nested 'or' condition

回答1:

You specific query could be:

crit.add(Restrictions.eq("a", "abc"));
crit.add(Restrictions.in("b", new String[] { "def", "ghi" });

If you're wondering about ANDs and ORs in general, do this:

// Use disjunction() or conjunction() if you need more than 2 expressions
Disjunction aOrBOrC = Restrictions.disjunction(); // A or B or C
aOrBOrC.add(Restrictions.eq("b", "a"));
aOrBOrC.add(Restrictions.eq("b", "b"));
aOrBOrC.add(Restrictions.eq("b", "c"));

// Use Restrictions.and() / or() if you only have 2 expressions
crit.add(Restrictions.and(Restrictions.eq("a", "abc"), aOrBOrC));

This will be equivalent to:

where x.a = 'abc' and (x.b = 'a' or x.b = 'b' or x.b = 'c')

回答2:

Use a syntax more like (x.b IN ('def', 'ghi')).

来源：https://stackoverflow.com/questions/4206702/hibernate-criteria-query-nested-condition