Block in PL/SQL - Anonymous Block & Normal Block

Hi Everyone, Today's topic is PL/SQL block.

PL/SQL is a block-structured language whose code is organized into blocks.

A PL/SQL block consists of three sections:

Declaration,

Executable,

and Exception-handling sections.

In a block, the executable section is mandatory while the declaration and exception-handling sections are optional.

1) Declaration section

A PL/SQL block has a declaration section where you declare variables, allocate memory for cursors, and define data types.

2) Executable section

A PL/SQL block has an executable section. An executable section starts with the keyword BEGIN and ends with the keyword END. The executable section must have a least one executable statement, even if it is the NULL statement which does nothing.

3) Exception-handling section

A PL/SQL block has an exception-handling section that starts with the keyword EXCEPTION. The exception-handling section is where you catch and handle exceptions raised by the code in the execution section.

Types of PL/SQL blocks :

Named Block : Block who has name is known as Named Block. Functions or Procedures is an example of a named block. A named block is stored into the Oracle Database server and can be reused later.
Anonymous Block : A block without a name is known as anonymous block.

An anonymous block is not saved in the Oracle Database server, so it is just for one-time use. However,

PL/SQL anonymous blocks can be useful for testing purposes.

Example od Anoymous Block:

BEGIN   
 DBMS_OUTPUT.put_line ('Hello World!'); 
END;