- (Subtract)

Subtracts two numbers. This subtraction arithmetic operator can also subtract a number, in days, from a date.

Syntax

expression - expression

Arguments

expression

Is any valid Microsoft® SQL Server™ expression of any of the data types of the numeric data type category except the bit data type.

Result Types

Returns the data type of the argument with the higher precedence. For more information, see Data Type Precedence.

Examples

A. Use subtraction in a SELECT statement

This example returns the amount of the year-to-date revenues retained by the company for each book title.

USE pubs
GO
SELECT title,
   (
      (price * ytd_sales) * CAST( ( (100 - royalty) / 100.0 ) 
         AS MONEY)
      ) AS IncomeAfterRoyalty
FROM titles
WHERE royalty <> 0
ORDER BY title_id ASC
GO

Parentheses can be used to change the order of execution. Calculations inside parentheses are evaluated first. If parentheses are nested, the most deeply nested calculation has precedence. For example, the result and meaning of the preceding query can be changed if you use parentheses to force the evaluation of subtraction before multiplication, which in this case would yield a meaningless number.

B. Use date subtraction

This example subtracts a number of days from a datetime date.

USE pubs
GO
DECLARE @altstartdate datetime
SET @altstartdate = '1/10/1900 3:00 AM'
SELECT @altstartdate - 1.5 AS 'Subtract Date'

Here is the result set:

Subtract Date               
--------------------
Jan 8 1900  3:00PM          

(1 row(s) affected)

See Also

Data Types

Expressions

Functions

Operators

SELECT