FreeTDS Development Group

[Frediano Ziglio <freddyz77 AT tin.it>]

Il mar, 2002-11-26 alle 23:16, Lowden, James K ha scritto:
> > From: ZIGLIO Frediano [mailto:Frediano.Ziglio AT vodafoneomnitel.it]
> > Sent: November 26, 2002 11:36 AM
> > 
> > This patch solve RPC problem but open other possible problems... 
> > - dynamic do not want column names on data
> 
> Do you mean:
> 
> 1.  dynamic SQL doesn't require named parmeters
>   or
> 2.  TDS 7.0 can't pass named parameters?  
> 

Dynamic query on TDS5 (using TDS5_DYN_TOKEN) do not want named
parameters. Simply add a flags parameters to
tds_put_data_info/tds_put_data_info_length to disable parameters name
(or reset name in tds_submit_execute ??)

> 
> > - we do not use column_namelen (is this correct?)
> 
> I don't think any of us knows yet if it's correct or not.  :(
> 

In TDSCOLINFO we have column_name and column_namelen... If column_name
is NUL terminated column_namelen is just a duplicate information that
can be out of sync...

> > - correct to use column_flags? 
> 
> Depends on the protocol; we'll have to experiment.  Certainly, 
> 
> +++
> 
> I've attached a note about SQLBindParameter from MSDN (ODBC Implementation
> Details), in case you haven't seen it.  It supports output parameters.  
> 

I know, I know. Is our libtds that do not full support output
parameters. The patch I send fix the problem but my question still
remain. When we read flags from db we split it on bit (like
column_writable, column_nullable, etc). There are no flag for "this is
an output parameters"... The patch store this information on
column_flags... Another variable that duplicate informations and can
became out of sync...

> In db-lib, named parameter support in the protocol is required.  The app
> calls dbrpcparam once for each parameter, but not in any particular order.
> TDS 5.0 passes them by name; the server returns them by name.    Names are
> not required (they can be passed positionally), but db-lib does not have
> enough information to map names to positions.  
> 

Yes and not, named parameters do not require a position. If you want to
use position just pass unnamed parameters in a given order. Also what's
the meaning of mixing named and unnamed?
exec sp_test 1, @test = 'a', 2
2 is the second or third parameter ??

> This fast and loose name-and-numbers philosophy mirrors T-SQL as in:
> 
> sp_adduser 'Figaro', 'Hero', 'Opera'
> 
>       could also be 
> 
> sp_adduser 'Figaro', @grpname = 'Opera', @name_in_db = 'Hero'
> 
> Don't know if we're on the same page yet.  HTH.  
> 
I think so :)

freddy77