On Sat, May 16, 2015 at 7:39 PM, Daniel Begin <jfd553@hotmail.com> wrote:
> - How indexes are actually implemented in PostgreSQL (how pgsql point to a
> record from an index)?
>
Not an easy answer. An index can have different implementation types,
but for short each index has a pointer to the block on disk that
contain the tuple. And indexes are, of course, on disk stuff.
> - Could copying tables and indexes have had an effect on indexes?
>
Should not, but it could be.
> - How can I verify that some of the indexes were not corrupted?
>
Use explain, see pg_stat_user_indexes and do a reindex if you believe
an index is corrupted.
I would expect this being more likely an issue with the hard drive
(e.g., different seek times from the previous one).
Luca
