从具有相同输入的多个表中进行选择 (SQL SERVER 2005)

Question

如何将几个结果集合并为一个。假设我有这五个 sql 选择，它们都采用相同的“简单”输入 (10)：

SELECT agentid, latitude, longitude, availability, updated
FROM table1
WHERE agentid=10

SELECT email, name, phone, company
FROM table2
WHERE userid=10

SELECT COUNT(*) AS pt1num
FROM table3
WHERE agentid=10 AND propertytype<6

SELECT COUNT(*) AS pt2num
FROM table3
WHERE agentid=10 AND propertytype>6 AND propertytype<9

SELECT COUNT(*) AS pt3num
FROM table3
WHERE agentid=10 AND propertytype>8

如何 UNION 或 JOIN 或子查询，以便获得包含所有列的行； agentid、纬度、经度、可用性、更新、电子邮件、姓名、电话、公司、pt1num、pt2num、pt3num？

Answer 1

一种方法是使用公用表表达式，然后交叉连接它们

    with cte1 as ( 
    SELECT agentid, latitude, longitude, availability, updated
    FROM table1
    WHERE agentid=10)
    , cte2 as (

    SELECT email, name, phone, company
    FROM table2
    WHERE userid=10)

    , cte3 as (
    SELECT COUNT(*) AS pt1num
    FROM table3
    WHERE agentid=10 AND propertytype<6)

    , cte4 as (SELECT COUNT(*) AS pt2num
    FROM table3
    WHERE agentid=10 AND propertytype>6 AND propertytype<9)

    ,  cte5 as (
    SELECT COUNT(*) AS pt3num
    FROM table3
    WHERE agentid=10 AND propertytype>8)


SELECT [youfieldlist] 
FROM 
  cte1, cte2, cte3, cte4, cte5

另一种方法是使用内联视图

Select [your field list]
FROM (
SELECT agentid, latitude, longitude, availability, updated
FROM table1
WHERE agentid=10 ) t1,
(
SELECT email, name, phone, company
FROM table2
WHERE userid=10) t2, 
(
SELECT COUNT(*) AS pt1num
FROM table3
WHERE agentid=10 AND propertytype<6) t3,
(
SELECT COUNT(*) AS pt2num
FROM table3
WHERE agentid=10 AND propertytype>6 AND propertytype<9) t4,
(
SELECT COUNT(*) AS pt3num
FROM table3
WHERE agentid=10 AND propertytype>8) t5

只有当您知道每个选择只会返回一行时，这些才是真正合理的

您也可以使用局部变量来执行每个选择

DECLARE @agentid int, @latitude int , ... 
SELECT   @agentid = agentid,  @latitude = latitude, ...
        FROM table1
        WHERE agentid=10

DECLARE @pt1num int
 SELECT @pt1num  = COUNT(*)  
    FROM table3
    WHERE agentid=10 AND propertytype<6

，然后将它们选择出来

SELECT  @agentid agentid,  @latitude latitude, ... @pt1num...