A query is a request for data or information from a database table or combination of tables. This data may be generated as results returned by Structured Query Language (SQL) or as pictorials, graphs or complex results, e.g., trend analyses from data-mining tools.

One of several different query languages may be used to perform a range of simple to complex database queries. SQL, the most well-known and widely-used query language, is familiar to most database administrators (DBAs).

Any four uses of queries are as follows:

• To analyze data of a table.
• To create new table with records from one or more tables.
• To update or delete large volume of records at the same time.
• To perform mathematical calculations on selected groups of records.