SQL * Plus is made up of two distinct parts. These are (a) Interactive SQL (b) PL/SQL. Interactive SQL is designed to create, access and maintain all data structures like tables, indexes etc. It can also be used for interactive data manipulation.  Programmers can use PL/SQL to create programs for validation and manipulation of table data. PL/SQL adds to the power of interactive SQL and provides the user with all the facilities of a standard, modern day (4 GL) programming environment.

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