[freetds] BLOB retrieval

Alexis Nikichine alexis.nikichine at free.fr
Tue May 3 10:38:05 EDT 2005


Hello,

My current business amounts to dumping MS SQLServer tables that, among 
others, contain TEXT (or NTEXT) data.

Of course, they are always longer than the current textsize ;-)

I was happy enough to find that the associated text-pointer is returned 
in the BLOBINFO data structure, for each blob column.
I still need to know the length of that BLOB, so I can :

    SET TEXTSIZE @size_large_enough

and then :

    READTEXT Table.column @the_pointer 0 @size

My current guess is that I should augment the selected column with 
DATALENGTH( blob_column1), DATALENGTH( blob_column2 ) ...
which does not seems to be such a good idea, since automatically 
patching SQL requests in such a way sounds hard to me. Besides, I need 
to know those column names in advance.

Thanks for any help,

Alexis


More information about the FreeTDS mailing list