ejb-ql语句.txt

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EJB-QL语法
该语句由如下4部分组成：
1.必须的Select从句
2.必须的From从句
3.可选的Where从句
4.可选的Order By从句


Where从句
例如：Select Object(o) from Order as o where o.name IS NOT EMPTY

处理输入参数:

findProductByDescription(String s)

Select Object(p) from Product as p where p.description=?1


findUserByNameAndPwd(String name,String pwd)

Select Object(c) from Users as c where c.name=?1 and c.password=?2