Understanding SQL

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SQL is widely used across IT industry and is most common technology. We will be covering SQL topics in this article.

What is SQL?

SQL is structured query language which is a computer language for storing, manipulating and retrieving data stored in a relational database.

The standard SQL commands to interact with relational databases are CREATE, INSERT, SELECT, UPDATE, DELETE and DROP. These commands are classified into following groups based on their nature

DDL(Data Definition Language)

  • CREATE - Creates a new table or view of a table or other objects in databases.
  • ALTER - Modifies an database existing object or table.
  • DROP - Deletes an entire table, a view of a table.
  • Truncate - Delete the value stored in the table.
DML(Data Manipulation Language)

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