Introduction to SQL and PL-SQL

Introduction to SQL and PL-SQL or defined.

Structured Query Language (SQL)  

SQL is the standard command set that allows the users to interect with the relational database management system.

          All tasks related to relational data management creating table querying the database for information, modifying the data in the database, deleting them, granting access to users and so on can be easily performed using SQL. Different database vendors use different dialects of SQL.

Advantages of SQL:-  

१) SQL is coded without embedded data.

२)Porting could be required when the underlying database management system need to be upgraded or changed.

३) SQL as a language provide a greater degree of abstraction and is independent of the way it is implemented internally.

४)The language in addition to being simple and easy to learn can also handle complex situations.

५) SQL can also be used to define data structures,control access to the data, delete,insert,and modify occurrences of the data.

Procedural language/Structured Query Language:-  Pl/SQL is an extension of SQL which offers modern features such as data encapsulation, exception handling, handling, information,hiding and also brings programming capabilities to the relational databases.

 Pl/SQL block structure:-

            DECLARE (Optional)

                                          (1)

             BEGIN

                                          (2)

            EXCEPTION (Optional)

                                            (3)

             END;