T-SQL-将列传递给子查询以进行过滤

问题描述

我需要将列传递给子查询以进行过滤，但是我似乎无法使其正常工作。

我知道，如果我的子查询要返回单个列，那么我可以重新排列查询，这样就可以了，但是我需要子查询返回3列。

到目前为止，这是我的查询，它在抱怨：

 where c.location.Stdistance(l.location) is not null
 order by c.Location.Stdistance(l.location)

使用

无法绑定多部分标识符“ l.location”。

select
    l.*,city.*
from  
    listings l,(select top 1 c.UnicodeName,c.name,r.code as region,cn.code as country 
     from cities c
     inner join regions r on r.regionid = c.regionid
     inner join Countries cn on cn.CountryId = r.countryid
     where c.location.Stdistance(l.location) is not null
     order by c.Location.Stdistance(l.location)) as city

实际计划 https://www.brentozar.com/pastetheplan/?id=BkiRk-74P

城市和商家信息索引

CREATE SPATIAL INDEX [256_HHHH] ON [dbo].[Listings]
(
    [Location]
)USING  GEOGRAPHY_GRID 
WITH (GRIDS =(LEVEL_1 = HIGH,LEVEL_2 = HIGH,LEVEL_3 = HIGH,LEVEL_4 = HIGH),CELLS_PER_OBJECT = 256,PAD_INDEX = OFF,STATISTICS_norECOmpuTE = OFF,SORT_IN_TEMPDB = OFF,DROP_EXISTING = OFF,ONLINE = OFF,ALLOW_ROW_LOCKS = ON,ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
GO

CREATE SPATIAL INDEX [16_HHHH] ON [dbo].[Listings]
(
    [Location]
)USING  GEOGRAPHY_GRID 
WITH (GRIDS =(LEVEL_1 = HIGH,CELLS_PER_OBJECT = 16,ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
GO

解决方法

您要描述的是横向联接，其中联接的子查询使用listing表中的列。由于from子句中的逗号，此操作失败：某些数据库的确可以识别这种隐式横向联接，但不能识别SQL Server。

您必须明确说明连接类型（无论如何都是最佳做法）：使用cross apply。

select l.*,city.*
from  listings l
cross apply (
     select  top (1)  c.UnicodeName,c.name,r.code as region,cn.code as country from cities c
     inner join regions r on r.regionid = c.regionid
     inner join Countries cn on cn.CountryId = r.countryid
     where c.location.STDistance(l.location) is not null
     order by c.Location.STDistance(l.location) 
 ) as city

join sql-order-by sql-server