need explanation on Hibernate criteria -

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i new hibernate, when looking @ ancriteria example article; says:

you have no way control sql query generated hibernate, if generated query slow, hard tune query, , database administrator may not it.

but think criteria used generate clause of generated sql, , clause conditions added 1 one , has nothing query's performance, how understand above statement?

first understand usage of hibernate criteria. used fetch data database , sql generated hibernate itself. due configuration of eager fetch, hibernate might unnecessarily generate sql lot of columns , joins hamper performance. in sense, using hql better or sql if cant achieve in hql (which should not case)


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