Databases

I am currently on the job hunt right now and whenever I look at the qualifications there is always some type of database. So I decided to take a deeper dive into the different databases so I can start to understand the difference between them all.

MySQL

One of the most popular databases and you can see it everywhere. It is an open source relational database. So this means a couple of things, first off it is free to use which is probably why it is so popular, but what is a rational database? This means that the collection of data has predefined relations between them. The easiest way for me to think of it is they are a bunch of spread sheets but they all have one thing in common somehow.

PostgresSQL

The main difference between Postgres and MySQL is Postgres is more powerful and is an object relational database. This is similar to rational database but it is object oriented, similar to Python. Therefore, objects can have different classes to build on.

NoSQL

This is a non-relational database. MongoDB which can be free but also has a commercial package is NoSQL. There are 4 types of NoSQL databases. Document database, such as JSON files

Key-Value database, each item conatins a key and value and can only be obtained with the key

Wide Column stored, similar to MySQL that it is set up like a spreadsheet but there are no tabs and columns do not have to contain information in every row.

Graph database, stores data in nodes and edges. Nodes store information about people, places and things and edges store the relationship between these those things.