[HACKERS] Effect of caching hash bucket size while costing

2016-12-08 Thread Srinivas Karthik V
Dear PostgreSQL Hackers, I am working in PostgreSQL 9.4.* optimizer module. In costsize.c file and final_cost_hashjoin() function, the innerbucketsize is either: a) calculated using a cached copy OR b) calculated afresh using statistics captu

[HACKERS] Requesting some information about the small portion of source code of postgreSQL

2016-09-26 Thread Srinivas Karthik V
Dear PostgresSQL Hackers, I am working in optimizer module of postgreSQL 9.4.1. I am trying to return a subplan for a query instead of full plan. For this I need to return an intermediate plan (or path) from the DP lattice (i.e. from *RelOptInfo *standard_join_search() *at* allpaths.c) *instead

Re: [HACKERS] Changing the result set to contain the cost of the optimizer's chosen plan

2016-07-18 Thread Srinivas Karthik V
Tom Lane wrote: > >> Srinivas Karthik V writes: >> > Specifically, I have a Java program which calls >> > ResultSet rs = statement.executeQuery("explain select * from table"); >> > I would like to change PostgreSQL such that ResultSet rs should conta

[HACKERS] Changing the result set to contain the cost of the optimizer's chosen plan

2016-07-11 Thread Srinivas Karthik V
Hello, I am Srinivas and have been working inside PostgreSQL (mostly in the optimizer module and few times in the executor module). I would like to change PostgreSQL code such that it also returns the cost of the optimizer chosen plan to the Java program (through JDBC) as part of the result set.

[HACKERS] PostgreSQL 8.3 index page count clarification

2015-05-26 Thread Srinivas Karthik V
Hi, For the user created indexes in PostgreSQL 8.3.6, I would like to know which file or function populates the index data structure. Specifically, where in the code is index->tuples and index->pages values are fetched and updated. Regards and Thanks in Advance, Srinivas Karthik

[HACKERS] PostgreSQL 8.3 index page count clarification

2015-05-20 Thread Srinivas Karthik V
Hi, For the user created indexes in PostgreSQL 8.3.6, I would like to know in which table (eg: pg_tablename) the index-tuple-count and index-page-count meta-data statistics are stored. Regards and Thanks, Srinivas Karthik