一个关于条件判断的问题
在做一个select查询,条件由用户输入,如果用户选择any,该怎么处理呢 
 例如:select   *   from   tablename   where   field1=@field1   and   field2=@field2,...   
 如果用户@field1选了 "any ",field1=@field1这里怎么处理呢?
------解决方案--------------------select * from tablename  
 where field1=isnull(@field1, field1) and field2=isnull(@field2, field2) 
 ...
------解决方案--------------------select * from tablename where (field1=@field1 or @field1 is null) and (field2=@field2 or @field is null) 
 对空值处理一下就好了
------解决方案--------------------select * from tablename where (field1=@field1 or @field1 is null) and (field2=@field2 or @field2 is null) 
 对空值处理一下就好了 
------解决方案--------------------select * from tablename  
 where field1=isnull(@field1, field1) and field2=isnull(@field2, field2)