Implementing a total order ranking in PostgreSQL 8.3

Question

The issue with 8.3 is.....rank is introduced in 8.4.

consider the numbers [10,6,6,2]

I wish to achieve a rank of those numbers where the rank is equal to the th

Answer 1

If you want a row number equivalent to the window function row_number(), you can improvise in version 8.3 with a (temporary) SEQUENCE:

CREATE TEMP SEQUENCE foo;

SELECT nextval('foo') AS rn, *
FROM   (SELECT score FROM tbl ORDER BY score DESC) s

SQL Fiddle.
The subselect is necessary to order rows before calling nextval().

Note that the sequence (like any temporary object) ...

• is only visible in the same session it was created.
• hides any other table object of the same name.
• is dropped automatically at the end of the session.

To use the sequence in the same session repeatedly run before each query:

SELECT setval('foo', 1, FALSE);