Tuning the Schema - Professional SQL Server 2005 Performance Tuning - page 199

Table 8-2: Data Types (continued)

Group Type name Range Storage Comments

10 − 19 9 bytes S (scale) The maximum

number of digits to the
right of the decimal point.

−

20 28 13 bytes

−

29 38 17 bytes

Money − 922,337,203,685,

477.5808 to
922,337,203,
685,477.5807

8bytes n/a

smallmoney − 214,748.3648 to

214,748.3647

4bytes n/a

Approximate
Numerics

Float( n ) − 1.79E + 308 to Nvalue

Storage
1

n/a

− 308, 0

and 2.23E

2.23E −

− 308 − 24 4 bytes

to 1.79E + 308 25 − 53 8 bytes

Real − 3.40E + 38 to 4bytes. n/a

− 1.18E − 38, 0

and 1.18E − 38 to

3.40E + 38

Date and time Datetime January 1, 1753,

to December 31,
9999

8 bytes total.
Stored as 2 4
byte integers.

Accuracy is 3.33
milliseconds

smalldatetime January 1, 1900,

to June 6, 2079

4 bytes total.
Stored as 2 2
byte integers.

Accuracy is 1 minute

Character Char( n ) Non-Unicode

characters.

n bytes Fixed length. Always

occupies n bytes, even if
some bytes are unused.
Valid values for n range
from 1 − 8000.

Varchar( n ) Non-Unicode

characters

1byteforeach
stored
character.

Variable length. Valid
values for n range from
1

8000. If n is omitted the
default is 1. Unused bytes
do not occupy storage
space. However, 2
additional bytes are
added. These are used as
an offset indicating the
location of the string's
end. See ''Row Overflow
Considerations.''

−

Continued