SQL Server 2005 显示几个字段合并起来的字符串解决方案

SQL Server 2005 显示几个字段合并起来的字符串
例如：

select province+city+area+street as address from addressmst where address_id=28

其中province、city、street都有值，但是如果area的值为NULL的话，就会显示为NULL。

如果将为NULL的字段去掉，则显示address有值：
select province+city+street as address from addressmst where address_id=28

------解决方案--------------------

SQL code

select province+city+isnull(area,'')+street as address from addressmst where address_id=28
------解决方案--------------------
isnull(col1,'')+isnull(col2,'')+isnull(col3,'')+isnull(col4,'') 即可