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 t...@sss.pgh.pa.us wrote: Anastasia Lubennikova lubennikov...@gmail.com writes: 2015-03-24 18:01 GMT+04:00 Tom Lane t...@sss.pgh.pa.us: I wonder whether it'd be possible to teach GIN to support index_getnext instead. Initially it would probably

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 t...@sss.pgh.pa.us: Anastasia Lubennikova lubennikov...@gmail.com 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

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

2015-03-25 Thread Tom Lane
Anastasia Lubennikova lubennikov...@gmail.com writes: 2015-03-24 18:01 GMT+04:00 Tom Lane t...@sss.pgh.pa.us: 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 ...

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

2015-03-24 Thread Tom Lane
Anastasia Lubennikova lubennikov...@gmail.com 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

[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