wrong column size with SQLDescribeCol

[lupien1]

To dynamically set the length of a variable (Code in C) to store data, i use the ODBC API function SQLDescribeCol. When a smalldatetime column type from SQLServer is treat by SQLDescribeCol, the COLSIZE return by the function is 16 when YYYY-MM-DD HH:MM:SS contain 19 characters. This case overload my variable with a crashing result of my program.

Is it a known problem and how can it be fixed?

Thank you!

 

[mrdenny]

There is no problem. The number of characters displayed in a datetime field (or smalldatetime field) doen't matter. Dates and times are not stored the same way they are viewed. If you need to move it to a static number of columns do a convert or cast on your datetime field.

smalldatetime uses 4 btyes for storage
datetime uses 8 bytes for storage

select convert(varchar(20), DateTimeColumn)
from table1

Denny
MCSA (2003) / MCDBA (SQL 2000)

--Anything is possible. All it takes is a little research. (Me)

http://www.mrdenny.com

 

[lupien1]

There is something i don't understand. When Datetime type is treat by SQLDescribeCol, the Colsize return is 23 "YYYY-MM-DD HH:MM:SS.000". Why Datetime is correct but not smalldatetime?

I can't use your SELECT suggestion because our function build a structure dynamically with all table retreive by a previous SQLTables call.

Thank you!

 

[mrdenny]

No idea. I'd check with the C folks in the C forums.

Denny
MCSA (2003) / MCDBA (SQL 2000)

--Anything is possible. All it takes is a little research. (Me)

http://www.mrdenny.com