#SEQUENTIAL STRUCTURES HOW TO#

That is, whether the sequence is executed or not depends on the value of a condition. The IF statement lets you execute a sequence of statements conditionally. Often, it is necessary to take alternative actions depending on circumstances. The sequence structure simply executes a sequence of statements in the order in which they occur. The iteration structure executes a sequence of statements repeatedly as long as a condition holds true. A condition is any variable or expression that returns a Boolean value ( TRUE or FALSE). The selection structure tests a condition, then executes one sequence of statements instead of another, depending on whether the condition is true or false. They can be combined in any way necessary to deal with a given problem. Major Topics Overview Conditional Control: IF Statements Iterative Control: LOOP and EXIT Statements Sequential Control: GOTO and NULL Statements OverviewĪccording to the structure theorem, any computer program can be written using the basic control structures shown in Figure 3-1. Their proper use leads naturally to a well-structured program. Collectively, these structures can handle any situation. You learn how statements are connected by simple but powerful control structures that have a single entry and exit point.

#SEQUENTIAL STRUCTURES HOW TO#

This chapter shows you how to structure the flow of control through a PL/SQL program. 'Tis the set of the sails and not the gales Which tells us the way to go. Control Structures One ship drives east and another drives west With the selfsame winds that blow.

Sequential structures