Answer by Neall for How to select the nth row in a SQL database table?

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    mytableORDER BY    somefieldLIMIT 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.