Question

我的结果显示了我不想要的重复项。我们有一个列调用addresstypes，它返回一个B或L，具体取决于在db中输入的内容。如果选择B，则输入数据不正确，因为这是交付和合法地址。

在提取数据时，我得到了序列号等，但我得到了两次......那些在B＆amp; B中都有地址数据的数据。升。

这是我的查询 - 如何才能显示双行？

USE inventory
SELECT distinct
dbo.addressinfo.locationinfoid, dbo.equipmentlocationscurrent.serialnum,    dbo.addressinfo.addresstype
FROM dbo.equipmentlocationscurrent
full join dbo.addressinfo
on  dbo.equipmentlocationscurrent.locationinfoid = dbo.addressinfo.locationinfoid
where  (clientName = 'cps lease')
and (locationtype = 'merchant')
and (addresstype = 'b' or addresstype = 'l')
order by serialnum

结果样本

locationinfoid  serialnum
2887540       301-252-800   B
2887540       301-252-800   L

Answer 1

根据您的评论，因为您要为每个addresstype选择locationinfoid的哪个值无关紧要，请使用GROUP BY locationinfoid, serialnum与MAX：< / p>

SELECT
  a.locationinfoid, 
  e.serialnum, 
  MAX(a.addresstype)
FROM dbo.equipmentlocationscurrent AS e
full join dbo.addressinfo AS a on e.locationinfoid = a.locationinfoid
where clientName = 'cps lease'
 and locationtype = 'merchant'
 and addresstype = 'b' or addresstype = 'l'
GROUP BY a.locationinfoid, e.serialnum
order by serialnum;

这将为您提供locationinfoid的明确值。

Answer 2

Distinct返回选择列表中包含的任何列的所有不同记录。因此，如果addressinfo.locationinfoid，serialnum或addressinfo.addresstype的值不同，那么您将获得重复记录

在这种情况下，如果addresstypes和locationinfoid对中的每一个都有serialnum和addresstype对，那么您可能会看到两个不同的USE inventory SELECT distinct dbo.addressinfo.locationinfoid, dbo.equipmentlocationscurrent.serialnum FROM dbo.equipmentlocationscurrent full join dbo.addressinfo on dbo.equipmentlocationscurrent.locationinfoid = dbo.addressinfo.locationinfoid where (clientName = 'cps lease') and (locationtype = 'merchant') and (addresstype = 'b' or addresstype = 'l') order by serialnum，因此您将获得2个“重复”记录。包含返回值的编辑确认了这一点。

如果您不关心{{1}}，请不要将其包含在选择列表中。尝试：

{{1}}

Answer 3

你有很多选择，

从结果中排除地址类型并使用不同的
使用聚合功能和按功能分组
制作一个知道重复项的clausules的交叉联盟

如果您不想获取地址类型并且想知道重复项，我会以这种方式重写查询：

SELECT     A.locationinfoid, E.serialnum
FROM dbo.equipmentlocationscurrent E
inner join dbo.addressinfo A
on  E.locationinfoid = A.locationinfoid
where  (clientName = 'cps lease')
and (locationtype = 'merchant')
and (addresstype = 'b')
order by serialnum

INTERSECT

SELECT     A.locationinfoid, E.serialnum
FROM dbo.equipmentlocationscurrent E
inner join dbo.addressinfo A
on  E.locationinfoid = A.locationinfoid
where  (clientName = 'cps lease')
and (locationtype = 'merchant')
and (addresstype = 'L')
order by serialnum

如果您只想获取它们，则不要在您的选择中使用不同的

包含AddressType

 SELECT  DISTINCT   A.locationinfoid, E.serialnum
    FROM dbo.equipmentlocationscurrent E
    FULL join dbo.addressinfo A
    on  E.locationinfoid = A.locationinfoid
    where  (clientName = 'cps lease')
    and (locationtype = 'merchant')
    and (addresstype IN('b', 'l'))
    order by serialnum

你也可以使用像MAX或MIN这样的聚合函数给你的clausule，这样你就不需要使用你的独特clausule

SELECT  A.locationinfoid, E.serialnum, MAX(A.addresstype ) AS addresstype 
        FROM dbo.equipmentlocationscurrent E
        FULL join dbo.addressinfo A
        on  E.locationinfoid = A.locationinfoid
        where  (clientName = 'cps lease')
        and (locationtype = 'merchant')
        and (addresstype IN('b', 'l'))
        Group by  A.locationinfoid, E.serialnum
        order by serialnum

不显示重复项

3 个答案: