Frequently Asked Questions about SQL

Can SQL create web apps?

SQL is a very important part of most web apps. It is the language used to retrieve and update data from a database. Most modern web applications have three layers:

  • The User Interface – the web pages that users interact with.
  • The Business Logic Tier – this tier captures requests from the User Interface, and manipulates data based on the requirements of the application. The business tier often requests or updates information from or to the database as part of its work.
  • The Database – where data is stored.

Which SQL database should you use?

There is no one answer to this question. The major SQL databases include Oracle, Microsoft SQL Server, MySQL, and PostgreSQL. Each has unique features, scaling capabilities, technical requirements, and pricing. MySQL and PostgreSQL are both open source databases, so can be well suited to smaller budgets and early-stage applications. Oracle and Microsoft SQL Server are proprietary applications that provide greater levels of support and – in many cases – better scalability. They are, however, more expensive to license. When making a decision for RDBMS, you should consider what your current needs are and what they might be in 5 years. If you think that you may change databases in the future, be careful not to use the unique features of any given database.

What is the difference between SQL and NoSQL?

SQL is a programming language used for retreiving and updating data within relational databases. Relational databases store data in an "atomic" fashion. That is, each type of data is stored in different tables according to how the data is intended to be used. The various tables are connected through "keys." The schema (structure) of the data is generally designed for a specific application use.

NoSQL databases usually store hierarchical documents (usually in JSON format). These documents can be unstructured and can follow schemas that are dramatically different from other documents. NoSQL databases use a variety of querying languages.

Are SQL and MySQL the Same?

No – SQL is a relatively common language used across all relational database management systems (RDBMS).  MySQL is the brand name of one of the most popular RDBMS’.