Learning PostgreSQL - Configuration files

 As part of Learning PostgreSQL series, today we will discuss configuration files that are essential in administering PostgreSQL server. These files will always reside in PGDATA, data directory of the PostgreSQL cluster.

In some installation, the configuration files might reside in another location like in Ubuntu based distribution, if you installed the database software using package installation type, then there are chances that these files would reside in `/etc/postgresql/<version>/main/`.

Please note that you can always get the location of configuration file by connecting to the database. I have installed the database using package method on a Linux distribution.

Learning PostgreSQL - Installation

 If you have not viewed my last post, then I request you to please go and check it out. The last post is about the architecture of PostgreSQL database, and this post is in continuation of that series.

In this post, we will discuss, different ways of installing a PostgreSQL software. Most of the organizations use Linux to deploy their PostgreSQL database, so we will be discussing ways to install PostgreSQL software on a Linux.

This will be a long post, so I would suggest you to keep a cup of coffee or a tea handy 😉.

Before installation, we will first understand how PostgreSQL versioning works.

Learning PostgreSQL - Architecture

I have started learning a new database, i.e. PostgreSQL, which is a powerful and open source relational database system. 

This is something new that I am trying, so I will start this series where I will try to publish a post every week with what I learned. Basically, these posts are nothing but notes that I am taking during the learning journey of PostgreSQL database.

This can also help those who are also in the process of learning this database system, and to those who already learned PostgreSQL, it can be a refresher.

Without wasting more time in introduction, let's start with the Architecture of the PostgreSQL. For Oracle DBAs (someone like me 😉), I will try to compare it with Oracle terminology so that it may help or speedup the learning.

Difference between Recovery Window & Backup Window

Recovery Window :
A recovery window is a period of time that begins with the current time and extends backward in time to the point of recoverability. The point of recoverability is the earliest time for a hypothetical point-in-time recovery, that is, the earliest point to which you can recover following a media failure.
To configure a retention policy based on recovery window, use

 CONFIGURE RETENTION POLICY TO RECOVERY WINDOW no DAYS;  

RMAN Restartable Backups or Re-Initiating RMAN Backups

Using the restartable backups feature, RMAN can backup only those files that have not been backup since a specified date. You can use this feature after a failed backup to re-initiate that backup. The unit of restartability is a backup set.