SQL Server 对多个表列建立索引

Question

我编写了一个使用两列的查询，每一列都来自不同的表。我怎样才能为这些列建立索引，这可能吗？

select countryName, balance
from main.country c 
join main.person p on (c.countryId = p.countryId)
where balance = (select MAX(balance) 
                 from main.person p2 
                 join main.country c2 on (c2.countryId = p2.countryId)
                 where c.countryId = c2.countryId 
                   and p.countryId = p2.countryId)
order by countryName;

Answer 1

在SQL Server中，如果您想在不同表的列上创建索引，那么您可以创建Schema Bound View并在该 View 之上构建索引。

在您的情况下，创建一个架构绑定(bind) View :

CREATE VIEW MyBoundView
WITH SCHEMABINDING  
AS  
   -- YOU QUERY 
   select countryName, balance
   from main.country c join main.person p on(c.countryId=p.countryId)
   where balance=(select MAX(balance) from main.person p2 join main.country c2 
   on(c2.countryId=p2.countryId)
   where c.countryId=c2.countryId and p.countryId=p2.countryId)
   order by countryName;  

GO  

现在您可以在此绑定(bind) View 上使用两列创建索引:

--Example index on the bound view.  
CREATE UNIQUE CLUSTERED INDEX IDX_V1   
   ON MyBoundView (countryName, balance);  
GO  

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