ISNUMERIC (Transact-SQL)

Determines whether an expression is a valid numeric type.

Transact-SQL Syntax Conventions

Syntax

ISNUMERIC ( expression )

Arguments

• expression
  Is the expression to be evaluated.

Return Types

int

Remarks

ISNUMERIC returns 1 when the input expression evaluates to a valid numeric data type; otherwise it returns 0. Valid numeric data types include the following:

int	numeric
bigint	money
smallint	smallmoney
tinyint	float
decimal	real

A return value of 1 indicates that expression can be converted to at least one of the numeric types.

Note

   ISNUMERIC returns 1 for some characters that are not numbers, such as plus (+), minus (-), and valid currency symbols such as the dollar sign ($). For a complete list of currency symbols, see Using Monetary Data.

Examples

The following example uses ISNUMERIC to return all the postal codes that are not numeric values.

USE AdventureWorks;
GO
SELECT City, PostalCode
FROM Person.Address 
WHERE ISNUMERIC(PostalCode)<> 1;
GO

See Also

Reference

Expressions (Transact-SQL)
System Functions (Transact-SQL)
Data Types (Transact-SQL)

Other Resources

Using Monetary Data

Help and Information

Getting SQL Server 2005 Assistance

Change History

Release	History
12 December 2006	New content: Added the format descriptions for the input expression.
14 April 2006	New content: Added note about additional characters.