我正在使用PostgreSQL 9.1,需要帮助将多行连接到一个行中.我需要两张桌子.当我使用两个乘以array_agg()
的函数时,我得到的结果是重复的值.
桌子:
CREATE TABLE rnp (id int, grp_id int, cabinets varchar(15) );
INSERT INTO rnp VALUES
(1,'11','cabs1')
,(2,'11','cabs2')
,(3,'11','cabs3')
,(4,'11','cabs4')
,(5,'22','c1')
,(6,'22','c2');
CREATE TABLE ips (id int, grp_id int, address varchar(15));
INSERT INTO ips VALUES
(1,'11','NY')
,(2,'11','CA')
,(3,'22','DC')
,(4,'22','LA');
SQL:
SELECT DISTINCT
rnp.grp_id,
array_to_string(array_agg(rnp.cabinets)OVER (PARTITION BY rnp.grp_id), ',') AS cabinets,
array_to_string(array_agg(ips.address) OVER (PARTITION BY ips.grp_id), ',') AS addresses
FROM rnp JOIN ips ON rnp.grp_id=ips.grp_id
结果:
GRP_ID CABINETS ADDRESSES
11 cabs1,cabs1,cabs2,cabs2,cabs3,cabs3,cabs4,cabs4 NY,CA,NY,CA,NY,CA,NY,CA
22 c1,c1,c2,c2 DC,LA,DC,LA
And what I need is:
GRP_ID CABINETS ADDRESSES
11 cabs1,cabs2,cabs3,cabs4 NY,CA,
22 c1,c2 DC,LA
SQLFiddle中的示例:http://sqlfiddle.com/#!1/4815e/19
如果只使用一个表——SQLFIDLE:http://sqlfiddle.com/#!1/4815e/20,则没有问题
我错过了什么?因为JOIN,有可能这样做吗?