Strange cost estimation for foreign tables

Introduction As you know postgres_fdw extension using to access data stored in external PostgreSQL servers.  postgres_fdw provides has more transparent and standards-compliant syntax for accessing remote tables than dblink. Additionaly, this extension provides some options to control how cost estimation is done. One of them is “use_remote_estimate”.  The estimated cost of scanning a foreign table should be whatever ….Read more

17 August 2018 by 291 0

GiST index and siglen

This post is based on the talk by Oleg Bartunov on pgConf2018.RU It is imperative that a user be able to construct new access methods to provide efficient access to instances of nontraditional base types Michael Stonebraker, Jeff Anton, Michael Hirohama. Extendability in POSTGRES , IEEE Data Eng. Bull. 10 (2) pp.16-23, 1987 Introduction On February ….Read more

12 February 2018 by 280 0

PostgreSQL Log Shipping or when it’s advisable

Introduction Recently we were approached by one of our clients with an interesting task. The fact is that he has a large database, around 1.5 TB. He also has several standbys from this primary server. The main task is to get the opportunity to perform long analytical queries, and also to connect using ETL tools to the ….Read more

12 January 2018 by 1444 5

Installing Ora2Pg and migration cost assessment

OVERVIEW To migrate the data from Oracle to Postgres, we using the utility Ora2Pg. Ora2Pg is a free tool used to migrate an Oracle or MySQL database to a PostgreSQL compatible schema. It connects your Oracle database, scan it automatically and extracts its structure or data, it then generates. Ora2Pg can be used from reverse engineering ….Read more

6 December 2017 by 336 0

PostgreSQL 10.1, 9.6.6, 9.5.10, 9.4.15, 9.3.20, and 9.2.24 released!

Corrective updates are available for all supported PostgreSQL branches: 10.1, 9.6.6, 9.5.10, 9.4.15, 9.3.20 and 9.2.24, which contain a batch of bug fixes, including fixes for problems that could lead to data corruption. The release of updates for the 9.3 branch will last until September 2018, 9.4 until December 2019, 9.5 until January 2021, 9.6 ….Read more

10 November 2017 by 322 0