Structured query language or SQL is a way to store and organise information in a relation database. SQL is used by a range of popular databases including Microsoft SQL Server and Microsoft Access, Oracle’s database solutions as well as Sybase. SQL works like this: it uses relations (more commonly known as tables) to store data and matches data across tables using features that are shared by the dataset.
According to Cobb’s notion it is possible to look up data in database using a query which is driven by a structured query language. Cobb went ahead and used SQL to store data in objects (tables) which also contained a schema describing the layout of the data – including a description for every column that represents a field. A single SQL record is a single row in the table.
Distinctive feature of SQL databases
There are very real differences between SQL and NoSQL databases, stretching across the language used to address the database through to the database structure.
Language used in SQL databases
Because SQL databases use a structured language it makes SQL databases very versatile, the structured nature explains part of the reason why SQL is so incredibly popular. However, a very structured approach can also involve restrictions: in the case of SQL it means that developers have to use schemas that are predefined, specifying how data is structured long before the database is populated.
Data must follow this structure which can mean spending a long time fitting your data into your SQL structure. There is a benefit to this structure in many applications: accounting applications and other legacy systems which depends on multi-row transactions are a close fit for SQL. NoSQL on the other hand offers more flexibility which is better for other types of applications.
The scalability of SQL
SQL is scalable, but the scalability of SQL is limited to vertical scaling. In other words, most SQL database servers see improved performance from adding fast processing, more storage and more RAM. However, NoSQL servers can scale horizontally by simply adding more servers, which gives admins more flexibility to scale.
One of the benefits of SQL is that it is so incredibly established that there is a large community that can answer key questions, and it is easy to build new skills in SQL. There are also countless user forums which can give support when needed. NoSQL is less established in comparison.
Should you choose SQL?
It is key to pick the right database for your application before you start because it has real repercussion on the development process and your ability to be flexible and scalable later. There is a benefit in that SQL databases have four decades of history and a really mature community offering free support, while numerous commercial vendors offer SQL databases.
However, NoSQL is often cheaper and open source and its unstructured nature offers a certain type of flexibility. It really just depends on what your specific application needs.