Question

我在StackOverflow和互联网上搜索过但没有找到任何解决方案。我有一个像SQL Server 2008 R2中的myTable这样的表，包含以下列： person_id，city，addressType，line_num，textarea以及其他一些列，但不需要这些列。所有字段都是int类型，但textarea的类型为varchar（10）。一个人可以在一个城市拥有多种类型的地址。地址可以很大，因此每种地址类型可以有多个行号。地址类型1是家庭地址，地址类型2是办公室地址，地址类型3是其他地址。这里给出了示例行

person_id|city|addressType|line_num|textarea
1        |1   |1          |0       |House no.
---------------------------------------------
1        |1   |1          |1       |10
---------------------------------------------
1        |1   |2          |0       |Building5
---------------------------------------------
1        |1   |2          |1       |Floor 1
---------------------------------------------
1        |1   |3          |0       |Factory
---------------------------------------------
1        |1   |3          |1       |no. 30

我需要在一行中显示所有类型的地址。就像这样：

person_id|city|homeAddress |officeAddress    |otherAddress
1        |1   |House no.,10|Building5,Floor 1|Factory,no.30

我用过加入。对于地址类型1和地址类型2，加入工作正常。

这是单连接的查询，工作正常：

SET ANSI_PADDING ON;
SELECT DISTINCT homeAddress_person_id, homeAddress_city, homeAddress, officeAddress
FROM
/*Sub query for home address*/
(SELECT person_id AS homeAddress_person_id, city AS homeAddress_city,
/*Concatinating home address*/
STUFF((SELECT ',' + textarea FROM myTable WHERE person_id=ResultsFrom_myTable_For_homeAddress.person_id AND city=ResultsFrom_myTable_For_homeAddress.city AND addressType=ResultsFrom_myTable_For_homeAddress.addressType FOR XML PATH(''),TYPE).value('.','VARCHAR(4000)'),1,1,'') AS homeAddress
FROM myTable ResultsFrom_myTable_For_homeAddress WHERE person_id=1 AND addressType=1
GROUP BY person_id,city,addressType) ResultsFrom_myTable_For_homeAddress_outer

FULL OUTER JOIN
/*Sub query for office address*/
(SELECT person_id AS officeAddress_person_id, city AS officeAddress_city,
/*Concatinating office address*/
STUFF((SELECT ',' + textarea FROM myTable WHERE person_id=ResultsFrom_myTable_For_officeAddress.person_id AND city=ResultsFrom_myTable_For_officeAddress.city AND addressType=ResultsFrom_myTable_For_officeAddress.addressType FOR XML PATH(''),TYPE).value('.','VARCHAR(4000)')
,1
,1
,'') AS officeAddress
FROM myTable ResultsFrom_myTable_For_officeAddress
WHERE person_id=1 AND addressType=2
GROUP BY person_id,city,addressType) ResultsFrom_myTable_For_officeAddress_outer
ON ResultsFrom_myTable_For_homeAddress_outer.homeAddress_person_id=ResultsFrom_myTable_For_officeAddress_outer.officeAddress_person_id AND ResultsFrom_myTable_For_homeAddress_outer.homeAddress_city=ResultsFrom_myTable_For_officeAddress_outer.officeAddress_city
SET ANSI_PADDING OFF;

但是当我添加另一个联接以显示其他地址时。它显示错误在预期条件的上下文中指定的非布尔类型的表达式这是带有两个连接的查询

SET ANSI_PADDING ON;
SELECT DISTINCT homeAddress_person_id, homeAddress_city, homeAddress, officeAddress, otherAddress
FROM
/*Sub query for home address*/
(SELECT person_id AS homeAddress_person_id, city AS homeAddress_city,
/*Concatinating home address*/
STUFF((SELECT ',' + textarea FROM myTable WHERE person_id=ResultsFrom_myTable_For_homeAddress.person_id AND city=ResultsFrom_myTable_For_homeAddress.city AND addressType=ResultsFrom_myTable_For_homeAddress.addressType FOR XML PATH(''),TYPE).value('.','VARCHAR(4000)'),1,1,'') AS homeAddress
FROM myTable ResultsFrom_myTable_For_homeAddress WHERE person_id=1 AND addressType=1
GROUP BY person_id,city,addressType) ResultsFrom_myTable_For_homeAddress_outer

FULL OUTER JOIN
/*Sub query for office address*/
(SELECT person_id AS officeAddress_person_id, city AS officeAddress_city,
/*Concatinating office address*/
STUFF((SELECT ',' + textarea FROM myTable WHERE person_id=ResultsFrom_myTable_For_officeAddress.person_id AND city=ResultsFrom_myTable_For_officeAddress.city AND addressType=ResultsFrom_myTable_For_officeAddress.addressType FOR XML PATH(''),TYPE).value('.','VARCHAR(4000)')
,1
,1
,'') AS officeAddress
FROM myTable ResultsFrom_myTable_For_officeAddress
WHERE person_id=1 AND addressType=2
GROUP BY person_id,city,addressType) ResultsFrom_myTable_For_officeAddress_outer
ON ResultsFrom_myTable_For_homeAddress_outer.homeAddress_person_id=ResultsFrom_myTable_For_officeAddress_outer.officeAddress_person_id AND ResultsFrom_myTable_For_homeAddress_outer.homeAddress_city=ResultsFrom_myTable_For_officeAddress_outer.officeAddress_city

FULL OUTER JOIN
/*Sub query for other address*/
(SELECT person_id AS otherAddress_person_id,city AS otherAddress_city,
/*Concatinating office address*/
STUFF((SELECT ',' + textarea FROM myTable WHERE person_id=ResultsFrom_myTable_For_otherAddress.person_id AND city=ResultsFrom_myTable_For_otherAddress.city AND addressType=ResultsFrom_myTable_For_otherAddress.addressType FOR XML PATH(''),TYPE).value('.','VARCHAR(4000)'),1,1,'') AS otherAddress
FROM myTable ResultsFrom_myTable_For_otherAddress WHERE person_id=1 AND addressType=3
GROUP BY person_id,city,addressType) ResultsFrom_myTable_For_otherAddress_outer
ON ResultsFrom_myTable_For_homeAddress_outer.homeAddress_person_id=ResultsFrom_myTable_For_otherAddress_outer.otherAddress_person_id AND ResultsFrom_myTable_For_homeAddress_outer.homeAddress_city=ResultsFrom_myTable_For_otherAddress_outer.otherAddress_city;
SET ANSI_PADDING OFF;

上述查询有什么问题？

Answer 1

使用common table expression和条件聚合，我们可以清理此查询并将其转换为：

with cte as (
  select
      person_id
    , city
    , addressType
    , address = stuff((
        select ',' + i.textarea
        from myTable i
        where i.person_id = t.person_id
          and i.city = t.city
          and i.addressType = t.addressType
        order by line_num
      for xml path(''), type).value('.', 'varchar(4000)'), 1, 1, '')
from MyTable as t
group by person_id, city, addressType
)
select
    t.person_id
  , t.city
  , homeAddress   = max(case when t.addressType = 1 then t.address end)
  , officeAddress = max(case when t.addressType = 2 then t.address end)
  , otherAddress  = max(case when t.addressType = 3 then t.address end)
from cte as t
where t.person_id = 1
group by t.person_id, t.city

rextester演示：http://rextester.com/RWIQ34896

返回：

+-----------+------+--------------+-------------------+----------------+
| person_id | city | homeAddress  |   officeAddress   |  otherAddress  |
+-----------+------+--------------+-------------------+----------------+
|         1 |    1 | House no.,10 | Building5,Floor 1 | Factory,no. 30 |
+-----------+------+--------------+-------------------+----------------+

您的问题是addressType 0已回家，但您的查询正在使用addressType 1.我相信您可以对此查询进行适当的调整。

SQL查询显示同一个表上有多个连接的错误

1 个答案: