写一个1=1是为了后面的条件。这个SQL应该是在程序中拼出来的，程序中首先不能肯定后面的条件是否肯定会有，为了程序简单先加上where 1=1，后面的就可以直接拼接。如果不这样处理就需要在拼接后面的每一个条件时都要判断是不是where子句的第一个件条，以决定是否要在前面加and
public PageResults<OrderVo> find(Long oid, String name, String mobile, String ostatus,
Date time1, Date time2) {
this.userSessionFactoryCustomer();
this.userSessionFactoryOrder();
String queryString = "select o.id as id ,o.status as ostatus,o.createDate as createDate ,o.paidDate as paidDate ,o.collectionToolSendDate as collectionToolSendDate ,o.collectionToolSendLogisticId as collectionToolSendLogisticId,o.finishDate as finishDate ,o.remark as remark ,"
+ "o.amount as amount,o.thirdPartyPayment as paymode,ol.companyName as companyName, "
+ "c.name as name,c.mobile as mobile,ol.address as address "
+ "from orders.orders o, customer.customer c,orders.order_logistics ol "
+ "where o.customerId=c.id and ol.id=o.collectionToolSendLogisticId and o.valid=true ";
String queryCountString = "select count(*) from orders.orders o, customer.customer c,orders.order_logistics ol where o.customerId=c.id and ol.id=o.collectionToolSendLogisticId and o.valid=true";
if (oid!=null){
queryString += " and o.id = :oid";
queryCountString += " and o.id = :oid";
}
if(name != null && !"".equals(name)){
queryString += " and c.name = :name";
queryCountString += " and c.name = :name";
}
if(mobile != null && !"".equals(mobile)){
queryString += " and c.mobile = :mobile";
queryCountString += " and c.mobile = :mobile";
}
if( ostatus != null && !"".equals(ostatus)){
queryString += " and o.status = :ostatus";
queryCountString += " and o.status = :ostatus";
}
if(time1!=null){
queryString +=" and o.createDate >= :time1 and o.createDate <= :time2";
queryCountString += " and o.createDate >= :time1 and o.createDate <= :time2";
}
queryString += " order by o.createDate";
Query query = this.getSession().createSQLQuery(queryString)
.addScalar("id",StandardBasicTypes.LONG)
.addScalar("ostatus")
.addScalar("createDate")
.addScalar("paidDate")
.addScalar("collectionToolSendDate")
.addScalar("collectionToolSendLogisticId",StandardBasicTypes.LONG)
.addScalar("finishDate")
.addScalar("remark")
.addScalar("name")
.addScalar("mobile",StandardBasicTypes.STRING)
.addScalar("address")
.addScalar("amount")
.addScalar("companyName")
.addScalar("paymode")
.setResultTransformer(Transformers.aliasToBean(OrderVo.class));
Query queryCount = this.getSession().createSQLQuery(queryCountString);
if (oid!=null){
query.setParameter("oid", oid);
queryCount.setParameter("oid", oid);
}
if(name != null && !"".equals(name)){
query.setParameter("name", name);
queryCount.setParameter("name", name);
}
if(mobile != null && !"".equals(mobile)){
query.setParameter("mobile", mobile);
queryCount.setParameter("mobile", mobile);
}
if(ostatus != null && !"".equals(ostatus)){
query.setParameter("ostatus", ostatus);
queryCount.setParameter("ostatus", ostatus);
}
if(time1!=null){
query.setParameter("time1",time1);
query.setParameter("time2",time2);
queryCount.setParameter("time1",time1);
queryCount.setParameter("time2",time2);
}
int size = SystemContext.getSize();
int offset = SystemContext.getOffset();
query.setFirstResult(offset).setMaxResults(size);
List<OrderVo> olist = query.list();
PageResults<OrderVo> olistpage = new PageResults<OrderVo>();
olistpage.setResults(olist);
olistpage.setCurrentPage(offset);
olistpage.setPageSize(size);
BigInteger totalCount=(BigInteger)queryCount.uniqueResult();
olistpage.setTotalCount(totalCount.intValue());
return olistpage;
}
}
where 1=2 是让记录集为空，因为只是用来插入一行，只需要得到表的各属性的数据类型即可。
速度较快 因为它不用和表内任何字段比对
本文出自 “点滴积累” 博客，请务必保留此出处http://tianxingzhe.blog.51cto.com/3390077/1679353
