How to select the nth row in a SQL database table?

Question

I\'m interested in learning some (ideally) database agnostic ways of selecting the nth row from a database table. It would also be interesting to see how this can b

Answer 1

PostgreSQL supports windowing functions as defined by the SQL standard, but they're awkward, so most people use (the non-standard) LIMIT / OFFSET:

SELECT
    *
FROM
    mytable
ORDER BY
    somefield
LIMIT 1 OFFSET 20;

This example selects the 21st row. OFFSET 20 is telling Postgres to skip the first 20 records. If you don't specify an ORDER BY clause, there's no guarantee which record you will get back, which is rarely useful.