Hibernate Dao操作总结

Hibernate

1. 使用构建器：

   //1. 获取条件构建
   CriteriaBuilder criteriaBuilder = getSession().getCriteriaBuilder();
   //2. 创建条件构造器
   CriteriaQuery cq = criteriaBuilder.createQuery(User.class);
   //3. 指定根条件
   Root root = cq.from(User.class);
   //4. 指定查询条件
   List predicates = new ArrayList<>();
   if (StringUtils.isNotEmpty(email)) {
       predicates.add(criteriaBuilder.and(criteriaBuilder.equal(root.get("name"), name)));
   }
   if (StringUtils.isNotEmpty(accountId)) {
       predicates.add(criteriaBuilder.and(criteriaBuilder.equal(root.get("sex"), sex)));
   }
   cq.where(predicates.toArray(new Predicate[0]));
   //5. 查询数据
   return getSession().createQuery(cq).getResultList();
   

2. NativeSql:

   //1. 创建本地sql
   String nativeSql = "select " +
           "a.id,a.name,a.sex,b.num " +
           "from tableA a,tableB b where a.id = b.id " +
           "and a.email = :email";
   //2. 创建
   Query query = getSession().createNativeQuery(nativeSql, User.class);
   //3. 执行
   query.setParameter("email", email).getResultList()
   

3. Hsql：（可以实现使用自定义类作为数据载体）

String sql = "select new com.hytto.data.model.wear.UserDTO(pid,count(id) AS count) " +
        "from User u where status = ‘a‘ and pid in (:patterns)  GROUP BY email";
        
List list = getSession().createQuery(sql)
                .setParameter("patterns", patternIdList)
                .getResultList();

原文：https://www.cnblogs.com/gronbu1/p/15339740.html