Oracle PL/SQL Programming, Third Edition

The Numeric FOR Loop

There are two kinds of PL/SQL FOR loops: the numeric FOR loop and the cursor FOR loop. The numeric FOR loop is the traditional and familiar “counted” loop. The number of iterations of the FOR loop is known when the loop starts; it is specified in the range scheme found between the FOR and LOOP keywords in the boundary.

The range scheme implicitly declares the loop index (if it has not already been declared), specifies the start and end points of the range, and optionally dictates the order in which the loop index proceeds (from lowest to highest or highest to lowest).

Here is the general syntax of the numeric FOR loop:

FOR loop index IN [REVERSE] lowest number .. highest number
LOOP
   executable statement(s)
END LOOP;

You must have at least one executable statement between the LOOP and END LOOP keywords.

The following table summarizes the properties of the numeric FOR loop:

Property	Description
How the loop is terminated	The numeric FOR loop terminates unconditionally when the number of times specified in its range scheme has been satisfied. You can also terminate the loop with an EXIT statement, but this is not recommended.
When the test for termination takes place	After each execution of the loop body, PL/SQL checks the value of the loop index. When it exceeds the upper bound of the range scheme, the loop terminates. If the lower bound is greater than the upper bound of the range scheme, the loop never executes its body.
Reason to use this loop ...