如何在PostgreSQL中基于排序顺序添加序数ID字段

Question

I was wondering how to add a field to a table (eg country ) based on sorting some of its fields (eg ISO code)?

I searched around SO and found the following question , but the solution is based on MySQL. I tried to use the solution there in Postgres 9.3 and it's giving me an syntax error on := . What I tried is:

SELECT  l.*,
        @curRow := @curRow + 1 AS row_number
FROM    country l ORDER BY ISO
JOIN    (SELECT @curRow := 0) r;

How to adapt this to Postgres?

Answer 1

You can use the row_number() window function :

SELECT   country.*, ROW_NUMBER() OVER (ORDER BY iso)
FROM     country
ORDER BY iso