Question

I have a revision table and I need to be able the nth most recent update. I have a query that gives me the most recent revision record of enitity, but I need one for the nth most recent revision record.

revisions
--+---------+--------+----------+-------
id|entity_id|contents|revisor_fk|revised

The query must take input 0 to n. If the input is 0 it is the most recent, 1 is one revision back or second most recent, 2 is to revisions back or the 3rd most recent, etc. And if the input is more revisions back then the entity has revisions it should return no rows.

Any thoughts?

Answer 1

Assuming revised is the timestamp

SELECT fields
FROM revisions
WHERE entity_id = :your_entity_id
ORDER BY revised DESC
LIMIT :which_revision, 1