String_agg () işlevinden sonuç nasıl sıralanır

Bir masam var:

CREATE TABLE tblproducts
(
productid integer,
product character varying(20)
)

Satırlar ile:

INSERT INTO tblproducts(productid, product) VALUES (1, 'CANDID POWDER 50 GM');
INSERT INTO tblproducts(productid, product) VALUES (2, 'SINAREST P SYP 100 ML');
INSERT INTO tblproducts(productid, product) VALUES (3, 'ESOZ D 20 MG CAP');
INSERT INTO tblproducts(productid, product) VALUES (4, 'HHDERM CREAM 10 GM');
INSERT INTO tblproducts(productid, product) VALUES (5, 'CREAM 15 GM');
INSERT INTO tblproducts(productid, product) VALUES (6, 'KZ LOTION 50 ML');
INSERT INTO tblproducts(productid, product) VALUES (7, 'BUDECORT 200 Rotocap');

Ben yürütmek durumunda string_agg()üzerinde tblproducts:

SELECT string_agg(product, ' | ') FROM "tblproducts"

Aşağıdaki sonucu döndürecektir:

CANDID POWDER 50 GM | ESOZ D 20 MG CAP | HHDERM CREAM 10 GM | CREAM 15 GM | KZ LOTION 50 ML | BUDECORT 200 Rotocap

Toplanan dizeyi kullanacağım sıraya göre nasıl sıralayabilirim ORDER BY product?

PostgreSQL 9.2.4 kullanıyorum.

Postgres 9.0+ ile şunları yazabilirsiniz:

select string_agg(product,' | ' order by product) from "tblproducts"

Detaylar burada .

https://docs.microsoft.com/en-us/sql/t-sql/functions/string-agg-transact-sql?view=sql-server-2017

SELECT
  STRING_AGG(prod, '|') WITHIN GROUP (ORDER BY product)
FROM ... 

select string_agg(prod,' | ') FROM 
  (SELECT product as prod FROM tblproducts ORDER BY product )MAIN;

SQL FIDDLE