question about numeric type

Hi,
I am kind of confused regarding the numeric data type. If I define a numeric
column to be precision 38 (the maximum allowed), in EM the column length
automatically turns to be 17. What's the relationship between 38 and 17?
Thanks
Those are storage bytes, lookup decimal and numeric in BOL
Precision Storage bytes
1 - 9 5
10-19 9
20-28 13
29-38 17
Denis the SQL Menace
http://sqlservercode.blogspot.com/
Jen wrote:
> Hi,
> I am kind of confused regarding the numeric data type. If I define a numeric
> column to be precision 38 (the maximum allowed), in EM the column length
> automatically turns to be 17. What's the relationship between 38 and 17?
> Thanks
|||what is Storage bytes? Thanks
"SQL Menace" wrote:

> Those are storage bytes, lookup decimal and numeric in BOL
> Precision Storage bytes
> 1 - 9 5
> 10-19 9
> 20-28 13
> 29-38 17
> Denis the SQL Menace
> http://sqlservercode.blogspot.com/
>
> Jen wrote:
>
|||How many bytes on disk a value of that datatype requires.
Tibor Karaszi, SQL Server MVP
http://www.karaszi.com/sqlserver/default.asp
http://www.solidqualitylearning.com/
"Jen" <Jen@.discussions.microsoft.com> wrote in message
news:E236F084-6DDA-46E6-9AC2-447ED7E1E364@.microsoft.com...[vbcol=seagreen]
> what is Storage bytes? Thanks
> "SQL Menace" wrote:
|||Is it true that if the length is 17, then the minimum digits wil be 29 and
the maximum digits will be 38? Thanks
"Tibor Karaszi" wrote:

> How many bytes on disk a value of that datatype requires.
> --
> Tibor Karaszi, SQL Server MVP
> http://www.karaszi.com/sqlserver/default.asp
> http://www.solidqualitylearning.com/
>
> "Jen" <Jen@.discussions.microsoft.com> wrote in message
> news:E236F084-6DDA-46E6-9AC2-447ED7E1E364@.microsoft.com...
>
|||No, that is now how it work. Compare to int vs. smallint, for instance. You would be saying that an
int cannot hold numbers lower than some 32767? That is not the case. A larger storage area can hold
a larger *span* of values. We are not really talking about digits, we are talking about the values
that these digits represent. The values can be represented as binary, 10 base decimal or
hexadecimal, us humans tend to prefer a 10 base decimal representation.
Tibor Karaszi, SQL Server MVP
http://www.karaszi.com/sqlserver/default.asp
http://www.solidqualitylearning.com/
"Jen" <Jen@.discussions.microsoft.com> wrote in message
news:622544A1-7A46-434A-A539-82D3C5052A52@.microsoft.com...[vbcol=seagreen]
> Is it true that if the length is 17, then the minimum digits wil be 29 and
> the maximum digits will be 38? Thanks
> "Tibor Karaszi" wrote:
|||Jen,
If you define a column as decimal/numeric with size 29, then each value
will use 17 bytes of disk space. A column defined as decimal(29,0) can
hold the values -99999999999999999999999999999 thru
99999999999999999999999999999.
If you define the column as decimal(30,0), you can store even bigger
numbers (one decimal digit more). However, each value will still use
(only) 17 bytes of disk space. The same is true for a decimal(38,0).
If you define the column as decimal(28,0), you can 'only' store numbers
between -9999999999999999999999999999 and 9999999999999999999999999999.
However, for the values of this column only 13 bytes of disk space are
needed per value.
HTH,
Gert-Jan
Jen wrote:[vbcol=seagreen]
> Is it true that if the length is 17, then the minimum digits wil be 29 and
> the maximum digits will be 38? Thanks
> "Tibor Karaszi" wrote: