mssql sqlserver两条求和sql脚本相加的方法分享

转自:http://www.maomao365.com/?p=7205

摘要:
下文分享两条sql求和脚本，再次求和的方法分享

 ／*
     例:
       下文已知两条sql求和脚本，现需对两张不同表的求和记录再次求和   
     */  
     ---对两条求和sql脚本求和的方法
      select sum(q) from 
      (
       select sum(qty)  as q from tableNameA where ...
       union all 
        select sum(qty)  as q from tableNameB where ...
       ) as table
     
     ---对多条求和sql脚本，再次求和的方法分享
     select sum(q) from 
      (
       select sum(qty)  as q from tableNameA where ...
       union all 
        select sum(qty)  as q from tableNameB where ...
         union all 
        select sum(qty)  as q from tableNameC where ...
        union all 
        select sum(qty)  as q from tableNameD where ...
       ...  
    ) as table