单列中的多行

Question

我使用POSTGRESQL 9.1.3作为后端，VS2010 c＃作为前端。 我有两张表如下：

属性

Property_id   Property_details
------------------------------
1             abc
2             xyz

言过其实

Claimer_ID  First_name  Last_Name Property_id
---------------------------------------------
1           aaaa        bbbbb       1
2           cccc        ddddd       2
3           eeee        fffff       1
4           gggg        hhhhh       2

我想要关注输出

Property_id   Claimers
------------------------------------
1             aaa bbbb,eeee ffff
2             ccc dddd,gggg hhhh
3             (may be more than 2 claimers)

此处claimer是一个列，可能包含1个或多于1个（最多50个）的请求者名称

我该怎么做？

Answer 1

SELECT  a."Property_id",
        array_agg(b."First_name" || ' ' || b."Last_Name") AS "Claimers"
FROM    Property a
        INNER JOIN Claimers b
            ON a."Property_id" = b."Property_id"
GROUP BY a."Property_id"

• SQLFiddle Demo
• array_agg