分为好多方面这里我们就具体Hibernate查询用例子来加以介绍说明希望对读者
学习带来帮助
1、支持
串方式参数传递查询:例子:
List students = session.createQuery("select s.id,s.name from Student s where s.name like '%1' ").list
;
for (Iterator iter=students.iterator; iter.hasNext;) {
Object
o = (Object)iter.next;
.out.pr
ln(o[0]+","+o[1]);
} 由于
涉及到多个属性查询所以返回是Object
类型2、支持类似于PrepareStatement方式
？传递参数查询例子:
List students = session.createQuery("select s.id,s.name from Student s where s.name like :goodname ")
.
Parameter("goodname", "%1%").list;
for (Iterator iter=students.iterator; iter.hasNext;) {
Object o = (Object)iter.next;
.out.prln(o[0]+","+o[1]);
} 要设置参数从0开始
见第2行3、去变量方式参数传递
例子:
List students = session.createQuery("select s.id,s.name from Student s where s.name like :goodname ")
.Parameter("goodname", "%1%").list;
for (Iterator iter=students.iterator; iter.hasNext;) {
Object o = (Object)iter.next;
.out.prln(o[0]+","+o[1]);
} 这个跟2中
相似只是多了参数可以归为
类4、支持多参数传递
例子:
List students = session.createQuery("select s.id, s.name from Student s where s.id in(:myids)")
.ParameterList("myids", 
Object{1, 2, 3, 4, 5,32,13,14})
.list;
for (Iterator iter=students.iterator; iter.hasNext;) {
Object o = (Object)iter.next;
.out.prln(o[0]+","+o[1]);
} 注意
思路方法是ParameterList5、
数据库里面
例子:
List students = session.createQuery("select s.id, s.name from Student s where date_format(s.createTime, '%Y-%m')=?")
.Parameter(0, "2008-10")
.list;
for (Iterator iter=students.iterator; iter.hasNext;) {
Object o = (Object)iter.next;
.out.prln(o[0]+","+o[1]);
} 数据库
date_format6、直接支持sql查询
例子:
List students = session.createSQLQuery("select *from t_student").list;
for (Iterator iter=students.iterator; iter.hasNext;) {
Object o = (Object)iter.next;
.out.prln(o[0]+","+o[1]);
} 只需要
session里面createSQLQuery思路方法即可7、进行导航查询
例子:
List students = session.createQuery("select s.name from Student s where s.
es.name like '%1%'").list;
for (Iterator iter=students.iterator; iter.hasNext;) {
String s = (String)iter.next;
.out.prln(s);
} 这种查询很方便
8、分页查询
例子:
List students = session.createQuery("from Student").FirstResult(0).MaxResults(3).list;
for (Iterator iter=students.iterator; iter.hasNext;) {
Student student = (Student)iter.next;
.out.prln(student.getName);
} 这是很简单
分页查询分页查询实现比这个复杂多了分页查询采用相当于数据库里面 limit 来限制次查询显示条数注:还有
些其他就不列举了Hibernate查询在Hibernate使用中HQL查询语言如果用得好会给工作带来比较高效率比较重要而且还有个查询效率问题这涉及到缓存Cache等方面以后会更新这方面文章
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