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public interface Restriction
A restriction query element. This is a query element that can appear
in the WHERE and HAVING part of a Query.
Typically a restriction consists of a condition which must be true for a
row if it should be returned. For example:
SELECT ... FROM ... WHERE id = 2
Implementation note! Do not create restrictions that use user input directly
in the queries. Always create a parameter (Expressions.parameter(String)
and use the Query.setParameter(String, Object, Type) method to specify the value.
Using parameters also makes it possible to execute the same query multiple times
with different parameter values.
ItemQuery<User> query = User.getQuery();
query.restrict(
Restrictions.eq(
Hql.property("name"),
Expressions.parameter("name")
)
);
// Generated HQL
SELECT usr
FROM UserData usr
WHERE usr.name = :name
query.setParameter("name", "Nicklas");
List nicklasList = query.list(dc);
query.setParameter("name", "Johan");
List johanList = query.list(dc);
Restrictions can be created by the Restrictions factory class.
Restrictions| Method Summary |
|---|
| Methods inherited from interface net.sf.basedb.core.query.QueryElement |
|---|
getChildren, toQl |
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