Re: [HACKERS] GSoC 2015 proposal. Bitmap Index-only Count

2015-03-27 Thread Alexander Korotkov
On Wed, Mar 25, 2015 at 11:07 PM, Tom Lane wrote: > Anastasia Lubennikova writes: > > 2015-03-24 18:01 GMT+04:00 Tom Lane : > >> I wonder whether it'd be possible to teach GIN to support index_getnext > >> instead. Initially it would probably work only for cases where the > >> index didn't have

Re: [HACKERS] GSoC 2015 proposal. Bitmap Index-only Count

2015-03-25 Thread Tom Lane
Anastasia Lubennikova writes: > 2015-03-24 18:01 GMT+04:00 Tom Lane : >> I wonder whether it'd be possible to teach GIN to support index_getnext >> instead. Initially it would probably work only for cases where the >> index didn't have to return any columns ... but if we did it, maybe the >> door

Re: [HACKERS] GSoC 2015 proposal. Bitmap Index-only Count

2015-03-25 Thread Anastasia Lubennikova
2015-03-24 18:01 GMT+04:00 Tom Lane : > Anastasia Lubennikova writes: > > There is a problem of slow counting in PostgreSQL [1]. The reason why > this > > is slow is related to the *MVCC* implementation in PostgreSQL. Index-only > > scans (implemented since PostgreSQL-9.2) providing some performa

Re: [HACKERS] GSoC 2015 proposal. Bitmap Index-only Count

2015-03-24 Thread Tom Lane
Anastasia Lubennikova writes: > There is a problem of slow counting in PostgreSQL [1]. The reason why this > is slow is related to the *MVCC* implementation in PostgreSQL. Index-only > scans (implemented since PostgreSQL-9.2) providing some performance > improvements where the *visibility map* of

[HACKERS] GSoC 2015 proposal. Bitmap Index-only Count

2015-03-24 Thread Anastasia Lubennikova
Hi, hackers! Here is the text of my proposal which I've applied to GSoC. (and link http://www.google-melange.com/gsoc/proposal/public/google/gsoc2015/lubennikovaav/5657382461898752 ) Any suggestions and comments are welcome. *Project name* Bitmap Index-only Count *Brief review* There is a p