PL/SQL stands for Procedural Language extension of Structured Query Language (SQL). It is a block-structured language having logical blocks which are made up of three sub-blocks i.e. a declarative part, an executable part and an exception building part. PL/SQL is integrated with Oracle and the functionalities of PL/SQL extend after each release of Oracle database.

It includes procedural language elements like conditions and loops and allows declaration of constants and variables, procedures and functions. It also helps the users to develop complex database applications using control structures, procedures, modules, etc. PL/SQL is not limited by any case-sensitive letters so you are free to use lower case letters or upper case letters.