A database query is a means for extracting data from a database and formatting it in a readable form. When you’re searching for data from a database, you can submit a query to request specific information. However, a query needs to be written in a language that can be processed by the database management system. For relational databases, this is usually Structured Query Language, or SQL.

SQL and Databases

Databases are complex file systems for organizing and collecting data information like products, customers, orders, employees and more. They are optimized for fast and secure storage, update and retrieval of data.

SQL queries are used to control and retrieve the specific information within the database. SQL programs are put in place by businesses as a way to access and manipulate the data stored within the databases. They are also used to create and alter new tables.

While it may seem a simple programming language, SQL is incredibly powerful. Commands can insert data into tables, modify data in existing database tables and delete data from tables. It can also modify the structure of the database itself using the same processes.

SQL Commands

SQL uses a set of commands to manipulate the data, including the SQL INSERT command, which adds data to database tables; the SQL SELECT command, which retrieves data from database tables; and the SQL UPDATE command, which modifies existing records. The SELECT statement returns data in rows and columns similar to a spreadsheet. This makes the information easy to view and work with, unlike query languages that return data as a graph or chart.

Using Queries

A database has the capability to store large volumes of complex data, allowing a user to reveal trends, patterns and insights through analysis. This is only possible through queries, however. The complex information in a database consists of multiple tables and large volumes, which a query filters into simplified tables to analyze effectively.

Queries can also be used to perform calculations on the data or automate data management. Queries may allow you to review updates to data before committing them to the database as well, which keeps your data clean and organized.