Arithmetic Operators

Arithmetic operators perform mathematical operations on two values or more.

Syntax

+ operator::=

Add Arithmetic Operator

- operator::=

Sub Arithmetic Operator

* operator::=

Multiple Arithmetic Operator

/ operator::=

Division Arithmetic Operator

Usage Notes

For '+' operator: 

  • If you add a decimal value to a timestamp, the result depends on the session/system parameter TIMESTAMP_ARTITHMETIC_BEHAVIOUR:
    • When TIMESTAMP_ARTITHMETIC_BEHAVIOUR = 'INTERVAL' - the decimal is rounded to an integer, and a certain number of full days are added (this is similar to function ADD_DAYS).
    • When TIMESTAMP_ARTITHMETIC_BEHAVIOUR = 'DOUBLE' - the fraction of days are added (hours, minutes, ...).
  • When adding the number of years or months (for example, INTERVAL '3' MONTH) on a date whose day is the last day of the month, then the last day of the resulting month is returned (similar to ADD_MONTHS).

For '-' operator

  • The difference between two datetime values depends on the session/system parameter TIMESTAMP_ARITHMETIC_BEHAVIOR:
    • TIMESTAMP_ARITHMETIC_BEHAVIOR = 'INTERVAL' - the result is an interval (similar to function DAYS_BETWEEN).
    • TIMESTAMP_ARITHMETIC_BEHAVIOR = 'DOUBLE' - the result is a double.
  • The difference of a date and a decimal is similar to the + operator with a negative value, thus subtracting days instead of adding them.
  • The difference between two interval values return an interval.
  • When subtracting the number of years or months (for example, INTERVAL '3' MONTH) on a date whose day is the last day of the month, then the last day of the resulting month is returned (similar to ADD_YEARS and ADD_MONTHS).
Example
SELECT 1000 + 234                                           ADD1,
DATE '2000-10-05' + 1                                       ADD2,
DATE '2009-01-05' + INTERVAL '1-2' YEAR TO MONTH            ADD3,
100000 - 1                                                  SUB1,
DATE '2000-10-05' - 1                                       SUB2,
DATE '2009-01-05' - INTERVAL '2' MONTH                      SUB3,
100 * 123                                                   MUL,
100000 / 10                                                 DIV;