Databases SQL, NoSQL, and differences in database models
In this article we will look at different types of both the database and the database. Try to understand the internal logic of their work and the main differences.
Today is difficult to imagine an application that does not use a database, whether the server, personal computers or mobile devices. From simple games to serious business applications. They all worked up read and write a particular data set.
A database management system (DBMS / DBMS) – software designed to store and manage data. In order to solve various problems developed more and more different RDBMS (relational and NoSQL) and programs to work with them (MySQL, PostgreSQL, MongoDB, Redis, etc.)
The relational model
Shotgun approach (NoSQL)
NoSQL (NewSQL) database
Comparison of SQL and NoSQL databases
The term database involves a fairly large number of very different from each other tools for working with databases (individual programs and shared libraries). Since these come in various forms and types, from the second half of the 20th century was designed by a huge number of different databases, and other applications to work with the database.
DBMS based on the model of the database – a special structure designed to operate with the data. All databases are very different in how they store and process their data.
Although there are many solutions to work with databases, popular and in demand are just some of them. The most commonly used today – relational database management system.
Each system supports a variety of models and database structures. This model defines how to create the database will handle data. There is quite a bit of database models, which provide a clear means of structuring data, the most popular of these models – the relational model.
The relational model and relational database can be a very powerful tool, but only if the programmer knows how to handle them. Recently began to gain popularity of NoSQL systems with the promise to get rid of the old database problems and add new features. Excluding rigid data structure, while maintaining the relational style, these databases offer a free way to work with them and the much greater opportunities for customization. Although not without costs and the emergence of new problems.
The relational model
Introduced in 1970, the relational model is a mathematical way of structuring, storage and use. In fact, he has expanded the flat and network model, combining them into a relational. The main advantage of which was the unification of the data in the group, it has allowed the relational model to store data in a structured tabular form (name, address).
Through decades of development, database reached a fairly high level of performance and fault tolerance. Experience of developers and network administrators, it was proved that all these tools are an excellent job with its functions in applications of any complexity, do not lose data even if the incorrect shutdown.
Despite great restrictions on the formation and management of data, relational databases maintained extensive customization capabilities and offer a rather large functional.
Unstructured approach (NoSQL)
NoSQL removes all restrictions of the relational model (lack of performance, time-consuming scaling, poor performance in a cluster) and facilitates the means of storing and accessing data. Such a database using an unstructured approach (creation of a structure on the fly), thereby removing the restrictions of rigid connections and offering different types of access to specific data.
The purpose of this article – to acquaint you with the basic paradigms of database systems. It is difficult to voice a certain decision, but usually have to choose between the relational model and NoSQL. Before you start looking for the difference, let’s look at the internal processes.
Relational database management systems take their name from the database model that works. At the moment, and probably in the near future, these databases are the most popular choice for data storage.
Relational databases are used strictly described data structure – scheme. The database schema includes a description of the content, structure and integrity constraints i.e. it defines the tables, the fields in each table, and the relationships between fields and tables.
Some of the most popular systems:
- SQLite – a fairly powerful embedded database
- MySQL – the most popular databases
- PostgreSQL – the most professional database freely available, full compliance with the SQL standard
Note: This article comparing relational database, you can find more information about the RDBMS.
NoSQL (NewSQL) database
NoSQL databases do not work with the relational model. There are many different solutions, each of which works a little differently, and serves a specific purpose. These solutions bezskhemnye remove restrictions on the formation of the entity and allow storage in the form of key-value.
Unlike relational databases, data collection can be grouped with other NoSQL databases such as MongoDB. DBMSs store data such as one in the base. Such data may be a single object as JSON yet correctly responding to fields.
NoSQL databases do not share a common request format, such as SQL for relational databases. Each NoSQL solution uses its own query system.
Note: For more information about NoSQL, you can read our article: Comparison of database NoSQL
Comparison of SQL and NoSQL database management systems
For an overall picture, let’s compare these two types of databases:
- Sturuktury data and their types – relational database using rigorous data schema, NoSQL databases allow any type of data
- Request – regardless of the license type, relational databases in one way or another to the SQL standard, so the data from them can be obtained by using the SQL language. NoSQL databases using specific methods to query data.
- Scalability – both types of DBMS is quite easily the vertical scaling (ie, an increase in system resources). However, as NoSQL is a modern product, it is such a DBMS offer easier ways to scale out (ie the creation of a cluster of several machines).
Reliability – when it comes to data security and performance guarantees transactional SQL database continues to occupy a leading position.
- Support – Relational databases do not have a small story behind. They are very popular and offer both paid and free solutions. If you have problems, yet much easier to find the answer when it comes to relational systems than NoSQL, especially if the solution is quite complex in nature (eg MongoDB).
- Storage and access to complex data structures – originally relational systems involves working with complex structures, which is why they are superior to other solutions on the performance.
Having any question about relational vs non relational database You can ask freely