Expressions calculate values by combining variables, columns, functions, constants, and operators. Expressions define computed columns and assign values to variables. Expressions are mathematical or text formulas used to calculate new values by manipulating existing values.
Expressions combine existing values using operators. Operators used in expressions determine the type of calculations to make. The list of operators that can be used in R:BASE expressions are displayed in the table below:
Operator |
Type |
Example |
+ |
Unary plus |
SET VARIABLE var1 = +.var1 |
- |
Unary minus |
SET VARIABLE var1 = -.var1 |
** |
Exponentiation |
SET VARIABLE var1 = (.var2**2) |
* |
Multiplication |
SET VARIABLE var1 = (.var2 * 100) |
/ |
Division |
SET VARIABLE var1 = (.var2 / 100) |
+ |
Addition |
SET VARIABLE var1 = (.var2 + 1) |
- |
Subtraction |
SET VARIABLE var1 = (.var2 - 1) |
+ |
Concatenation (w/o space) |
SET VARIABLE var1 = ('light' + 'bulb')
Result = lightbulb |
& |
Concatenation (w/space) |
SET VARIABLE var1 = ('light' & 'bulb')
Result = light bulb |
You can use any data type in an expression. The binary and character large object data types (BIT, BITNOTE, LONG VARBIT, LONG VARCHAR, VARBIT, AND VARCHAR), although they are valid only in equality operations, are not recommended for use in expressions. The Data Type Results Table listed below displays the data type results when specific data type values are used:
Data Type |
Yields |
CURRENCY |
CURRENCY (However, dividing CURRENCY by CURRENCY yields DOUBLE) |
DATE |
•DATE – DATE = INTEGER (days) •DATE + INTEGER = DATE •DATE – INTEGER = DATE |
DATETIME |
DATETIME – DATETIME = DATETIME (smallest specified time unit) |
TIME |
•TIME – TIME = INTEGER (smallest specified time unit) •TIME + INTEGER = TIME •TIME – INTEGER = TIME |
TEXT |
Either TEXT or NOTE.
A TEXT expression can contain only text strings, text functions, or concatenation operators (+ or &). |
NOTE |
Either NOTE or TEXT.
A NOTE expression can contain only text strings, text functions, or concatenation operators (+ or &). |
INTEGER |
Depends on data types of the other elements and on order of calculation in the expression.
•INTEGER + REAL = REAL •INTEGER + DOUBLE = DOUBLE |
See Also
Rules for Defining Expressions
