This operator is used to sum two numbers.
result = expression1 + expression2
You can use the + operator to concatenate two character strings, but you may not be able to determine whether addition or string concatenation will occur. As an alternative, use the & operator for concatenation to eliminate ambiguity and to provide self-documenting code.
The following table shows how the underlying subtype of the expressions determines the behavior of the + operator.
If |
Then |
| Both expressions are numeric | Add |
| Both expressions are strings | Concatenate |
| One expression is numeric and the other is a string | Add |
If one or both expressions are Null expressions, result is Null. If both expressions are Empty, result is an Integer subtype. If only one expression is Empty, the other expression is returned unchanged as result.