需求:一次查询出某个实体的各种状态的数量,在主页展示一个报表
- 方案一:每次发送一条SQL查询一个状态
- 方案一:只执行一条SQL根据status进行分组,select status, count(id) from tableName group by status
方法二如下
public Map<Integer, Long> getCountByOrgId(Integer orgId) {
StringBuffer hqlString = new StringBuffer(" select status, count(id) from tableName where charityOrgId.id= " +orgId+" group by status");
List list =getSession().createQuery(hqlString.toString()).list();
Map<Integer, Long> result=new HashMap<Integer, Long>();
if (list!=null&&!list.isEmpty()) {
for(Iterator iterator = list.iterator();iterator.hasNext();){
Object[] objects = (Object[]) iterator.next();
result.put((Integer)objects[0], (Long)objects[1]);
}
}
return result;
}