FreeTDS Development Group

[Damien Churchill <damoxc AT gmail.com>]

On 7 May 2010 02:24, James K. Lowden <jklowden AT freetds.org> wrote:
> Damien Churchill wrote:
>> Is it possible to send an empty string as a parameter when making rpc
>> calls? All my efforts so far seem to result in the parameter ending up
>> being NULL when doing a trace on the server!
>
> It works.  Cf. src/dblib/unittests/rpc.c.
>
> I modified the .c and .sql of the unit test report errors if the NULL
> inputs don't arrive as NULL.  You might find the lastest revision a little
> clearer.
>
> http://manuals.sybase.com/onlinebooks/group-cnarc/cng1110e/dblib/@Generic__BookTextView/34413;pt=39614
>
> According to Sybase, "If the value of the RPC parameter is NULL, pass
> datalen as 0, even if type is a fixed-length datatype."  That's what the
> unit test does, and the server recognizes them as NULL.
>
> HTH.
>
> --jkl

>From that it looks like it isn't possible to just send an empty string
'' which of course is different to NULL? Is this a limitation of
db-lib or the TDS protocol?

Damien