Assignment Operators

Assignment operators are used in InfoSphere® DataStage® BASIC assignment statements to assign values to variables. Table 1 shows the operators and their uses.

Table 1. Assignment Operators
Operator Syntax Description
= variable = expression Assigns the value of expression to variable without any other operation specified.
+= variable += expression Adds the value of expression to the previous value of variable and assigns the sum to variable.
-= variable -= expression Subtracts the value of expression from the previous value of variable and assigns the difference to variable.
:= variable := expression Concatenates the previous value of variable and the value of expression to form a new value for variable.

Table 2 shows some examples of assignment statements.

Table 2. Examples of Assignment Statements
Example Interpretation
X = 5 This statement assigns the value 5 to the variable X.
X += 5 This statement is equivalent to X=X+5. It adds 5 to the value of the variable X, changing the value of X to 10 if it was originally 5.
X -= 3 This statement is equivalent to X=X-3. It subtracts 3 from the value of the variable X, changing the value of X to 2 if it was originally 5.
X := Y This statement is equivalent to X=X:Y. If the value of X is 'CON', and the value of Y is 'CATENATE', then the new value of the variable X is 'CONCATENATE'.