decimal and numeric (Transact-SQL)

decimal and numeric (Transact-SQL)

Community Content

In this section

Statistics Annotations (0)

Click here to expand

Collapse All

Other versions are also available for the following:

SQL Server 2005

decimal and numeric (Transact-SQL)

Numeric data types that have fixed precision and scale.

decimal [ (p[ ,s] )] and numeric[ (p[ ,s] )]

Fixed precision and scale numbers. When maximum precision is used, valid values are from - 10^38 +1 through 10^38 - 1. The ISO synonyms for decimal are dec and dec(p, s). numeric is functionally equivalent to decimal.

p (precision)

The maximum total number of decimal digits that can be stored, both to the left and to the right of the decimal point. The precision must be a value from 1 through the maximum precision of 38. The default precision is 18.

s (scale)

The maximum number of decimal digits that can be stored to the right of the decimal point. Scale must be a value from 0 through p. Scale can be specified only if precision is specified. The default scale is 0; therefore, 0 <= s <= p. Maximum storage sizes vary, based on the precision.

Precision	Storage bytes
1 - 9	5
10-19	9
20-28	13
29-38	17

Converting decimal and numeric Data

For the decimal and numeric data types, SQL Server considers each specific combination of precision and scale as a different data type. For example, decimal(5,5) and decimal(5,0) are considered different data types.

In Transact-SQL statements, a constant with a decimal point is automatically converted into a numeric data value, using the minimum precision and scale necessary. For example, the constant 12.345 is converted into a numeric value with a precision of 5 and a scale of 3.

Converting from decimal or numeric to float or real can cause some loss of precision. Converting from int, smallint, tinyint, float, real, money, or smallmoney to either decimal or numeric can cause overflow.

By default, SQL Server uses rounding when converting a number to a decimal or numeric value with a lower precision and scale. However, if the SET ARITHABORT option is ON, SQL Server raises an error when overflow occurs. Loss of only precision and scale is not sufficient to raise an error.

Conversion of float values that use scientific notation to decimal or numeric is restricted to values of precision 17 digits only. Any value with precision higher than 17 rounds to zero.

Reference

ALTER TABLE (Transact-SQL)

CAST and CONVERT (Transact-SQL)

CREATE TABLE (Transact-SQL)

DECLARE @local_variable (Transact-SQL)

SET @local_variable (Transact-SQL)

sys.types (Transact-SQL)