Selecting records randomly

Question

Relations are unordered by default but usually the output of a query is ordered by a special attribute(usually primary key) to make it more meaningful.
what in case if we want to select some records randomly without considering the time of data manipulation/insertion or any other attribute.

Answer 1

this might be handy

https://stackoverflow.com/questions/580639/how-to-randomly-select-rows-in-sql