Query tools- Structure Query Language

Query Tools 

Database are stored in the form of data files until the system needs to perform file processing file processing on the information. At that point, it is copied into RAM.

Database are sometimes too large to fit into RAM all at once, so only portion of the  total data can bee manipulated at any one time. To work with large amounts of data, database management system come equipped with query tools that help users narrow down the amount of information that needs to be searched. A Query allows users to ask questions designed to retrieve needed information. For example, a query combined with a report can be used to ask a grades database to list all students in the top 12 percent of academic achievements.
The result could be used to print report that would be the dean's list for the semester.

Structure Query Language

SQL is the most popular database query language. It is simple when compared with a programming language , but it is also "structured" meaning that it is not a freedom natural programming language that mimic human speech. SQL is a very commonly supported query format and works with the most databases in use today. Since it is standardized and so widely supported, SQL is often used to bridge communications gaps between database systems running on the computers employing different operating systems.