Trent Nelson wrote:
On Tue, Feb 25, 2003 at 10:12:52AM -0600, Mike Meyer wrote:
In <[EMAIL PROTECTED]>, Trent Nelson <[EMAIL PROTECTED]> typed:
I'm interested in seeing how well something like PostgreSQL can be
used as a ``drop-in'' replacement for Oracle. If I have clients
connecting via ODBC (Rational ClearQuest), I personally couldn't
care what the underlying database is. Now *that* is something I'd
be interested in seeing a write up for.
It's not a drop-in replacement. You have to install the PostgreSQL
ODBC drivers on all the clients. Any client-side scripts will have to
be changed to use a PostgreSQL wrappers instead of Oracle
wrappers. The SQL is probably subtly different as well.
SQL may be a standard, but you still get locked into the databases
that you can query with it.
Perhaps I should have been more specific. I'm interested in how far
you can get (i.e. what queries will work, what ones won't) before
you reach a complete road-block. With regards to ODBC, changing the
driver being used by the application's '*odbc.ini' configuration fi-
le is sufficient for modifying the database being interfaced to, is
it not? i.e. the application simply calls standard ODBC functions
which the individual database drivers implement.
It depends on how the application is written.
One of the "standard ODBC functions" available is an SQL passthru, which
basically lets the application talk directly to the SQL server it the SQL
server's native dialect of SQL. If the application uses this ability, it
probably won't work at all.
Additionally, there are different levels of ODBC compatibility, if your
application requires a certain level, and the PostgreSQL ODBC driver
doesn't support it, you're out of luck again.
Not to say that there isn't a possibility that it will work, just that
it's not a terribly simple question to answer.
The whole "ODBC compatiblity" thing is (unfortunately) a lie. Nobody has
stood up and constrained the standard enought to make it truely compatible
across all databases.
--
Bill Moran
Potential Technologies
http://www.potentialtech.com
To Unsubscribe: send mail to [EMAIL PROTECTED]
with "unsubscribe freebsd-questions" in the body of the message
