SQL stands for Structured Query Language is a very useful language to work with data of relational database files. It can be used to retrieve, filter, insert, delete, and update data, and make calculations on data of the database files by using statements that will be discussed in the subsequent sections of this tutorial.
The relational databases files store data in the form of table in which rows and columns are specified. The headers of columns define the fields of the data and each row is the record.
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