How To Loops In Oracle PL/SQL With Code Examples

Introduction:

Loops are essential constructs in any programming language, and Oracle PL/SQL is no exception. Loops allow you to repeatedly execute a block of code until a certain condition is met. In this blog post, we will explore different types of loops available in Oracle PL/SQL and provide code examples to illustrate their usage.

1. Basic Loop:
   The basic loop is the simplest type of loop in PL/SQL. It executes a block of code repeatedly until an exit condition is met. Here’s an example:

DECLARE
   counter NUMBER := 1;
BEGIN
   LOOP
      -- Code block to be executed
      DBMS_OUTPUT.PUT_LINE('Counter: ' || counter);

      counter := counter + 1;

      -- Exit condition
      IF counter > 5 THEN
         EXIT;
      END IF;
   END LOOP;
END;

In this example, the loop will execute the code block inside it five times, printing the value of the counter each time. The loop will exit when the counter exceeds 5.

2. WHILE Loop:
   The WHILE loop is used when you want to execute a block of code as long as a specific condition is true. Here’s an example:

DECLARE
   counter NUMBER := 1;
BEGIN
   WHILE counter <= 5 LOOP
      -- Code block to be executed
      DBMS_OUTPUT.PUT_LINE('Counter: ' || counter);

      counter := counter + 1;
   END LOOP;
END;

In this example, the code block inside the WHILE loop will be executed as long as the counter is less than or equal to 5. The value of the counter is printed, and the counter is incremented by 1 in each iteration.

3. FOR Loop:
   The FOR loop is used when you want to iterate over a range of values. It is especially useful when you know the number of iterations in advance. Here’s an example:

DECLARE
   counter NUMBER;
BEGIN
   FOR counter IN 1..5 LOOP
      -- Code block to be executed
      DBMS_OUTPUT.PUT_LINE('Counter: ' || counter);
   END LOOP;
END;

In this example, the FOR loop iterates over the values from 1 to 5 (inclusive). The code block inside the loop will be executed for each value of the counter.

Conclusion:

Loops are powerful constructs in Oracle PL/SQL that allow you to repeat a block of code until a specific condition is met. The basic loop, WHILE loop, and FOR loop provide different ways to control the flow of execution. By understanding and utilizing loops effectively, you can build more robust and efficient PL/SQL programs.

Remember to experiment with loops in PL/SQL by modifying the code examples provided to further enhance your understanding.