PL/SQL FOR and WHILE LOOP / Iterative Statements

Index - PL/SQL Tutorial

Introduction to PL/SQL
Chap 1 : Block structure and Advantages of PL/SQL
Chap 2 : PL/SQL Variables and Constants
Chap 3 : PL/SQL Records
Chap 4 : PL/SQL IF ELSE statement / Conditional statements
Chap 5 : PL/SQL FOR and WHILE LOOP / Iterative Statements
Chap 6 : Cursors in PL/SQL
Chap 7 : PL/SQL Procedures
Chap 8 : PL/SQL Functions
Chap 9 : Parameters-Procedure and Function in PL/SQL
Chap 10 : What are PL/SQL Triggers
Chap 11 : Exception Handling in PL/SQL

Introduction to PL/SQL LOOP Statement

PL/SQL LOOP is an iterative control structure that allows you to execute a sequence of statements repeatedly.

There are three types of PL/SQL loop Statements

• Simple Loop


• While Loop


• For Loop

Type 1) Simple Loop
A Simple Loop is used when a set of statements is to be executed at least once before the loop terminates. An EXIT condition must be specified in the loop, otherwise the loop will get into an infinite number of iterations. When the EXIT condition is satisfied the process exits from the loop.

Syntax :

LOOP
statements;
EXIT;
{or EXIT WHEN condition;}
END LOOP;


Type 2) While Loop
A WHILE LOOP is used when a set of statements has to be executed as long as a condition is true. The condition is evaluated at the beginning of each iteration. The iteration continues until the condition becomes false.

Syntax :

WHILE
LOOP statements;
END LOOP;


3) FOR Loop
A FOR LOOP is used to execute a set of statements for a predetermined number of times. Iteration occurs between the start and end integer values given. The counter is always incremented by 1. The loop exits when the counter reachs the value of the end integer.

Syntax :

FOR counter IN value1..value2
LOOP statements;
END LOOP;


value1 - Start integer value.
value2 - End integer value.