我用地址表中的外键创建了员工表。当我保存新员工时,我想检查表地址中是否已存在该地址,如果存在,则不在地址中创建新行,而是找到正确的行并将其保存在员工中。
我用 SQL 做了这个类似的过程,但是用 hibernate 做这个有更简单的方法吗?使用这段代码我总是有新的行。我尝试进行查询以提取,但我不知道如何使用此地址 ID 分配给员工,而不是在地址中插入新行。图片上是 table ,所以很明显我想要什么。 table look , link to project
Employee employee = new Employee();
Address address = new Address();
City city = new City();
/* Query query = session.createQuery("select a.address_id from Address
a where a.street = :addName").setParameter("addName" ,
JFClasss.insStreet.getText());
List list = query.list();
if(!list.isEmpty()){
addid = (int) list.get(0);
address.setAddressId(addid);
// save = 1;
} */
address.setStreet(jf.insStreet.getText());
city.setCityName(jf.insStreet.getText());
employee.setName(jf.insName.getText());
employee.setSurname(jf.insSurname.getText());
employee.setAge(age);
employee.setAddress(address);
employee.setCity(city);
session.saveOrUpdate(city);
session.save(address);
session.save(employee);
最佳答案
解决了,我可以获取整个对象并使用 saveOrUpdate 再次保存它。
Employee employee = new Employee();
Address address;
City city = new City();
Query query = session.createQuery("select a.address_id from Address a
where a.street = :addName").setParameter("addName" ,
JFClasss.insStreet.getText());
List list = query.list();
if(!list.isEmpty()){
addid = (int) list.get(0);
address = (Address) session.get(Address.class, addid);
// address.setAddressId(addid);
// save = 1;
}
else{
address = new Address();
address.setStreet(jf.insStreet.getText());
}
.
.
.
session.saveOrUpdate(address);
关于java - 如果数据存在则 hibernate 并保存正确的外键,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/48563784/