On Mon, Nov 14, 2016 at 4:45 AM, Magnus Hagander <mag...@hagander.net> wrote: > For a scenario like this, would it make sense to have an option that could > be set on an individual table making it physical append only? Basically > VACUUM would run as normal and clean up the old space when rows are deleted > back in history, but when new space is needed for a row the system would > never look at the old blocks, and only append to the end.
One thing I have idly wondered about: if you had an append-only mode that guarantees that we never write new tuples anywhere but the end of the heap, you could create a bsearch access method that uses zero storage and simply checks that every key inserted is >= the previous high key before allowing the insertion to proceed. Then it could make use of the guaranteed correlation with physical order to do scans using a binary search of the heap. Maybe that'd be useful for some kinds of write-only time-series data that needs to be searched by time range. On the other hand, BRIN indexes are tiny, should be nearly as good and are much less restrictive, so I haven't follow this thought up. -- Thomas Munro http://www.enterprisedb.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
