PL/SQL Introduction

PL/SQL Introduction:

•  PL/SQL is the procedural language which is used in oracle platform. 
•  PL/SQL enables program or Application developers to combine SQL with procedural statements.

 PL/SQL Block contains four sections,

   1. Declare(Optional)

   2. Begin(Mandatory)

   3. Exception(Optional)

   4. End(Mandatory)

Syntax:              

Declare                               Declaration statements ;  Begin       Executable statements ;  Exception      Exception handling statements ;  End;

Example:     

Declare     v_count number;  Begin        select count(*) into v_count        from emp;  Exception       when SQL%Notfound then             Dbms_Output.Put_line('No data found');  End;

Explanation:

Declare:

·       Declare section starts with DECLARE keyword in which constants, variables, cursors can be declared which stores data temporarily.

·       This Declare section is optional.

Execution:

·       Execution section starts with BEGIN and ends with END Keyword. program logic to be written here to perform any task, it support all

·       DDL, DML commands ,condition expressions etc.This section is Mandatory.

Exception:

·       It starts with Exception keyword. which is used to handle the run time errors in the executable section. This section is optional.

PL/SQL Main concepts:

  1. Procedures

  2. Functions

  3. Packages

  4. Triggers

  5. Cursors

  6. Exception handling

 

 

Share: