Before we start learning SQL, let's get acquainted with the basic concepts about databases. This will help us to understand the scope of SQL and its environment. execution.
A database is a set of data stored in a structured way
In fact, this is just a repository of some information, nothing more. Databases themselves would be of no interest if there were no database management systems.
database management system is a set of language and software tools that performs access to data, allows them to be created, modified and deleted, provides data security, etc.
In simpler terms, a DBMS is a system that allows create databases and manipulate information from them.
The simplest scheme for working with a database:
At the moment, the rating of database management systems based on db-engines is as follows:
- Oracle - relational DBMS
- MySQL - relational DBMS
- Microsoft SQL Server - relational DBMS
- PostgreSQL - relational DBMS
- MongoDB - document-oriented databases
- Redis - key-value databases
- IBM Db2 - relational DBMS
- Elasticsearch - search engine
- Microsoft Access - relational DBMS
- SQLite - relational DBMS
It can be noted that 7 of the 10 most popular DBMS are relational. You made the right choice to study them 😉.
Let's check how we learned the topic, choose the correct statement: