Oracle PL/SQL Programming, 5th Edition

The Simple Loop

The structure of the simple loop is the most basic of all the loop constructs. It consists of the LOOP keyword, the body of executable code, and the END LOOP keywords, as shown here:

LOOP
  executable statement(s)
END LOOP;

The loop boundary consists solely of the LOOP and END LOOP reserved words. The body must consist of at least one executable statement. The following table summarizes the properties of the simple loop:

Property	Description
How the loop is terminated	The simple loop is terminated when an EXIT statement is executed in the body of the loop. If this statement is not executed, the simple loop becomes a true infinite loop.
When the test for termination takes place	The test takes place inside the body of the loop, and then only if an EXIT or EXIT WHEN statement is executed. Therefore, the body—or part of the body—of the simple loop always executes at least once.
Reason to use this loop	Use the simple loop when: You are not sure how many times you want the loop to execute. You want the loop to run at least once.

This loop is useful when you want to guarantee that the body (or at least part of the body) will execute at least one time. Because there is no condition associated with the loop boundary that determines whether or not it should execute, the body of the loop will always execute the first time.

The simple loop will terminate only when an EXIT (or its close cousin, EXIT WHEN) statement is executed in its body, or when an exception is raised (and goes unhandled) ...