FreeTDS Development Group

[Frediano Ziglio <freddy77 AT gmail.com>]

2011/5/11 James K. Lowden <jklowden AT freetds.org>:
> On Mon, 9 May 2011 10:17:16 -0400
> Raymond R Rankins <rrr03 AT health.state.ny.us> wrote:
>
>> Exporting of DATE columns seems to work fine, but when importing into
>> a DATE column, I'm getting the "Msg 20049, Level 4 Data conversion
>> resulted in overflow" error.
>
> The upcoming release 0.91 will not support DATE or other types
> introduced in SQL Server 2008.  Support for these data types will take
> some time, probably the rest of this year at least unless someone
> contributes a patch.
>
> Reading DATE "works" because the server converts DATE to varchar
> (20) for clients using anything less than TDS Version 7.3.  A BCP
> upload requires the client to send DATE data in its binary 3-byte
> format (days since 0001-01-01).  Prior to TDS 7.3 no such type was
> defined.  If sent to a server using, say, TDS 7.2, the server would
> probably reject the packet and disconnect the session, even if the
> server supports TDS 7.3 and *could* recognize the datatype.
>
> Give Microsoft credit for backwards compatibility.  At the same time,
> recognize that "protocol versions" are not as flexible as feature
> negotiation.  To support DATE, we have to implement the whole of TDS
> 7.3.  We can't indicate to the server we'd like 7.2 with DATEs.
>
> To support just DATE, we need inter alia:
>
> 1.  convert DATE <-> varchar
> 2.  convert DATE <-> DATETIME
> 3.  convert DATE <-> SMALLDATETIME
> 4.  support e.g. db_bind for DATE
> 5.  add DATE to the conversion unit test
>
> I took an initial step today to support a TDS 7.3 login packet.  Once
> we can log in, the server will start sending and receiving DATE in its
> native form, and the work listed above can commence.  Before the next
> release, all 7.3 datatypes will need to be supported.  Frediano is even
> headed to MARS.  (MARS, though, *is* a negotiable protocol
> feature; you can be a 7.3 client with or without MARS support.)
>

I have a patch for 7.3, not complete obviously (or I would have
committed earlier). I'll commit the "right" part, login is supported.
The convert stuff is quite missing, I changed just some functions to
support dates from 1-1-1 (well... you can actually write and use this
date but I would remember to Microsoft that Gregorian calendar started
some centuries later :) ).

> So many features, so little time.
>

I perfectly agree with you.

James... what about git ??

Frediano