On Tue, Jan 4, 2011 at 4:09 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> * Existing GIN indexes are upwards compatible so far as on-disk storage
> goes, but they will of course be missing entries for empty, null, or
> null-containing items. Users who want to do searches that should find
> such items will need to reindex after updating to 9.1.
This is the only part of this proposal that bothers me a little bit.
It would be nice if the system could determine whether a GIN index is
"upgraded from 9.0 or earlier and thus doesn't contain these entries"
- and avoid trying to use the index for these sorts of queries in
cases where it might return wrong answers.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company