PostgreSQL - MC

PostgreSQL #4 - Physical Layer - Files In the last post in the blog I described most of PostgreSQL`s architecture. If you didnt read that post I suggest you to do it in order to help you  better   understand the things that I'm going to describe in this post and in the next posts. In the title of the post I mentioned "Physical Layer". One might ask - what does it mean ? In this post I'm going to talk about PostgreSQL`s file system layer.  I'm going to explain the importance and the meaning of the directories and the files that were created during the installation (check it out in the second post in the blog). I'm going to focus mainly on the data directory - pg_hba.conf,postgresql.conf, pg_xlog,base,pg_tblspc.   Installation directory When you installed PostgreSQL you had the option to choose where to install it. If you installed it via yum or you didnt manualy  choose  the installation directory it is likely that it was instal...

PostgreSQL #3 - Architecture In the last post in the blog I installed PostgreSQL version 9.6.3. If you still didnt install postgresql on your machine I recommend you to do that. I think that hands on is the best way to understand a new technology. In order to understand how PostgreSQL really works it is importand to understand its architecture. When you will realize and understand its architecture it will be much easier to explain and understand many postgresql mechanisms. When you start PostgreSQL`s instance (via pg_ctl start) the main process of the databases is started. In the past versions it was known as the postmaster process and now days it is called postgres. When this processes is started it allocates memory for two main things : shared memory and other background processes. The shared memory is a memory that the database uses mainly for cashing. Its main goal is to reduce the I/O operations and as a result of that improve the performance of the database. The ...

PostgreSQL #2 - Installation In this post I'm going to explain how to install PostgreSQL database server. I will try to make it clear as possible. You will find in the post the prerequisites, on what environment I'm working on and step by step instructions on how to install postgresql via yum or from source code. So, Lets begin :) Prerequisites You can find all the prerequisites in the official documentation . To be honest I looked at the prerequisites maybe once. If you are trying to create a production enivronment you should check the prerequisites. If you are just want to learn or create a test env just follow the post instructions and you'll be ok. My environment I dont have any server therefore I downloaded oracle virtualbox . I created a virtual machine on my laptop and installed centos 7 on it. You need to configure the machine so that it can access the internet. In other word if you can ping outside of your network you are good to go. I...

PostgreSQL #1 - Introduction Hi, My name is Mariel Cherkassky and I'm going to write in this blog all the things that I have learned so far about postgresql . I will try to explain anything from what it is to the most complicated things that I handled. Hopefully it will be usefull for some people someday.  ?So what is PostgreSQL PostgreSQL is a relational database (data stored in tables). PostgreSQL has many advantages in compare to other relational databases but you should remember that what makes it so unique is that it is an  open source  database. In other words the PostgreSQL project`s code is visible to the community. Every one can reach that code and help make this project better. As a result of that there are many helpfull tools in the field that can make our life easier whether you are developer,system administrator, dba or just someone that is trying postgresql. This huge attribute led to the creation of many PostgreSQL`s forks. In other word...