OLE DB driver

Shachar Shemesh wrote:

Hi all,

After unsuccessfully trying to join the current OLE DB project on
gborg, I'm writing my own. So far I don't have anything too fancy
(just trying to get over the initial shock of what OLE DB actually
is). It currently does the basic infrastructure, but does not yet
actually connect to Postgresql. If anyone else has written code, was
contemplating writing code, has access to the gborg project, or is
otherwise interested, please let me know.

I wonder if this could be implemented as a wrapper around libpq. This
way, the OLEDB driver would benefit from a proven piece of software.

Regards,
Andreas

Andreas Pflug wrote:

I wonder if this could be implemented as a wrapper around libpq. This
way, the OLEDB driver would benefit from a proven piece of software.

Regards,
Andreas

That's what I'm doing. I'm not sure why other drivers didn't do that as
well (maybe there was no native Windows port of libpq at the time?).

My reason is actually that I'm not a great postgres hacker, and I would
rather rely as little as possible on internal structures and things that
are likely to change in the future.

Shachar

--
Shachar Shemesh
Lingnu Open Systems Consulting
http://www.lingnu.com/

"Shachar Shemesh" <psql@shemesh.biz> wrote:3FFF1607.9090806@shemesh.biz...

Andreas Pflug wrote:

I wonder if this could be implemented as a wrapper around libpq. This
way, the OLEDB driver would benefit from a proven piece of software.

Regards,
Andreas

That's what I'm doing. I'm not sure why other drivers didn't do that as
well (maybe there was no native Windows port of libpq at the time?).

AFAIK, rely on libpq is a fast way but not always convenient.
OLEDB has many features borrowed from ODBC, and it is a
substitute for ODBC. Microsoft is now making ODBC obsolete and
advocating OLEDB instead. You'd better read pgodbc's source
code, too.

Shachar Shemesh wrote:

Andreas Pflug wrote:

I wonder if this could be implemented as a wrapper around libpq. This
way, the OLEDB driver would benefit from a proven piece of software.

Regards,
Andreas

That's what I'm doing. I'm not sure why other drivers didn't do that
as well (maybe there was no native Windows port of libpq at the time?).

My reason is actually that I'm not a great postgres hacker, and I
would rather rely as little as possible on internal structures and
things that are likely to change in the future.

Sounds good. While I probably won't find time helping implementing the
driver; I have an OLEDB app running that currently uses
MSDASQL/psqlODBC. I'd certainly like testing your driver, and give
feedback from that. When do you expect first usable versions?

Regards,
Andreas

Andreas Pflug wrote:

Sounds good. While I probably won't find time helping implementing the
driver; I have an OLEDB app running that currently uses
MSDASQL/psqlODBC. I'd certainly like testing your driver, and give
feedback from that.

That would be great.

When do you expect first usable versions?

That depends. I'm hoping to have a version that implements the basic
(read - mandatory) interfaces later this week. A more broad version will
take longer.

I also wanted to ask the list's opinion about a gborg/sourceforge
hosting. The current oledb project on gborg seems dead. Should I open
another one?

Shachar

--
Shachar Shemesh
Lingnu Open Systems Consulting
http://www.lingnu.com/

William ZHANG wrote:

"Shachar Shemesh" <psql@shemesh.biz> wrote:3FFF1607.9090806@shemesh.biz...

Andreas Pflug wrote:

I wonder if this could be implemented as a wrapper around libpq. This
way, the OLEDB driver would benefit from a proven piece of software.

Regards,
Andreas

That's what I'm doing. I'm not sure why other drivers didn't do that as
well (maybe there was no native Windows port of libpq at the time?).

AFAIK, rely on libpq is a fast way but not always convenient.

Seems like more convinent than hacking the client/server protocol
myself. I may come up to a wall later on, and then I may reconsider.

OLEDB has many features borrowed from ODBC, and it is a
substitute for ODBC. Microsoft is now making ODBC obsolete and
advocating OLEDB instead. You'd better read pgodbc's source
code, too.

I did some of that, and did some ODBC hacking too (very little). The
fact that ODBC uses it's own protocol implementation, I think, is a
mistake. There are places where some intervention is going to be
unavoidable, I'm afraid, but that has nothing to do with what protocol
to use for communicating with the back end. If Postgres doesn't support
writeable cursors, then it doesn't support writeable cursors. One has to
emulate them. I will defenitely use some borrowing from pgsqlODBC (the
main reason my OLE DB is LGPL was so I can do that).

--
Shachar Shemesh
Lingnu Open Systems Consulting
http://www.lingnu.com/

On Saturday 10 January 2004 13:55, Shachar Shemesh wrote:

Andreas Pflug wrote:

Sounds good. While I probably won't find time helping implementing the
driver; I have an OLEDB app running that currently uses
MSDASQL/psqlODBC. I'd certainly like testing your driver, and give
feedback from that.

That would be great.

When do you expect first usable versions?

That depends. I'm hoping to have a version that implements the basic
(read - mandatory) interfaces later this week. A more broad version will
take longer.

I also wanted to ask the list's opinion about a gborg/sourceforge
hosting. The current oledb project on gborg seems dead. Should I open
another one?

Can you fill us in on your efforts to contact the original project author? If
those efforts have failed and the code is no longer being maintained, we can
contact the gborg maintainer about making you the admin for the project. I
don't think there is an official policy on this, but this seems like a
reasonable request as long as your willing to either update the old code or
leave it as it's own seperate module within the cvs tree.

Robert Treat
--
Build A Brighter Lamp :: Linux Apache {middleware} PostgreSQL

-----Original Message-----
From: Shachar Shemesh [mailto:psql@shemesh.biz]
Sent: 11 January 2004 20:21
To: William ZHANG
Cc: pgsql-hackers@postgresql.org
Subject: Re: [HACKERS] OLE DB driver

AFAIK, rely on libpq is a fast way but not always convenient.

Seems like more convinent than hacking the client/server
protocol myself. I may come up to a wall later on, and then I
may reconsider.

Seems unlikely - libpq is the definitive implementation of the protocol.

I did some of that, and did some ODBC hacking too (very
little). The fact that ODBC uses it's own protocol
implementation, I think, is a mistake.

Yes, it would be easier if that were not the case - unfortunately that
decision was made many years ago -
http://pluto.iis.nsk.su/postgres95/postgres95.ODBC/

Regards, Dave.

Robert Treat wrote:

Can you fill us in on your efforts to contact the original project author?

Sure thing. Here it is:
The project is located at
http://gborg.postgresql.org/project/oledb/projdisplay.php. It has
released no code, shows no CVS activity, and seems rather empty. There
are two tasks listed, without any status attached to them. There was one
bug, which suggests that there used to be some code, but it's in
"submitted" state, and I'm not sure what it relates to.

The front page says "please email me if you want to join". However, I
could not locate the email address for "mosiu", the administrator.
Lastly, I used the form to ask to become a developer of this project
(about a month ago). I have received no answer of any kind. As such, I
reached the conclusion that this project is terminally dead, and that
it's code is unrecoverable.

If
those efforts have failed and the code is no longer being maintained, we can
contact the gborg maintainer about making you the admin for the project.

I would love it if you contacted him, but I don't even have the code for
the current project. The bug report seems to suggest that such a code
exists, but I'm damned if I can find it.

I
don't think there is an official policy on this, but this seems like a
reasonable request as long as your willing to either update the old code or
leave it as it's own seperate module within the cvs tree.

Like I said, there doesn't appear to be any old code to maintain. I have
requested a new project on gborg (pgoledb), but getting the current name
is just as good. If the current code is somehow recovered, I'll be more
than glad to have a look at it. After all - I don't INSIST on writing
from scratch.

Robert Treat

Shachar

--
Shachar Shemesh
Lingnu Open Systems Consulting
http://www.lingnu.com/

Chris,

do you have any additional info (email?) on how to contact the original
project admin? Is it possible for you to manually set up Shachar as admin on
the project?

Robert Treat

On Monday 12 January 2004 04:30, Shachar Shemesh wrote:

Robert Treat wrote:

Can you fill us in on your efforts to contact the original project author?

Sure thing. Here it is:
The project is located at
http://gborg.postgresql.org/project/oledb/projdisplay.php. It has
released no code, shows no CVS activity, and seems rather empty. There
are two tasks listed, without any status attached to them. There was one
bug, which suggests that there used to be some code, but it's in
"submitted" state, and I'm not sure what it relates to.

The front page says "please email me if you want to join". However, I
could not locate the email address for "mosiu", the administrator.
Lastly, I used the form to ask to become a developer of this project
(about a month ago). I have received no answer of any kind. As such, I
reached the conclusion that this project is terminally dead, and that
it's code is unrecoverable.

If
those efforts have failed and the code is no longer being maintained, we
can contact the gborg maintainer about making you the admin for the
project.

I would love it if you contacted him, but I don't even have the code for
the current project. The bug report seems to suggest that such a code
exists, but I'm damned if I can find it.

I
don't think there is an official policy on this, but this seems like a
reasonable request as long as your willing to either update the old code
or leave it as it's own seperate module within the cvs tree.

Like I said, there doesn't appear to be any old code to maintain. I have
requested a new project on gborg (pgoledb), but getting the current name
is just as good. If the current code is somehow recovered, I'll be more
than glad to have a look at it. After all - I don't INSIST on writing
from scratch.

Robert Treat

Shachar

--
Build A Brighter Lamp :: Linux Apache {middleware} PostgreSQL