Re: [Pypgsql-users] c-jdbc (or rather sqlrelay ?)

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Dick Kniep wrote:
> [...] So, what I want is
> a local connection to the database, with asynchronous updates to
> databases that are in the same 'logical' cluster of databases. c-jdbc
> looks like the proper candidate for this action, 

The description of c-jdbc looks neat, however I have my doubts wether it 
can work reliably because database replication is a very complex topic. 
I have no experience in it myself, but I briefly talked with a colleague 
who did create a whitepaper for adding database replication to an 
existing Oracle database. All I can say is that it gets complicated 
really quick.

> however no luck because
> we developed using Python.....

Well, there are multiple possibilities to use c-jdbc from Python 
nevertheless. I'd recommend to create a Java server proxy that uses JDBC 
and that you access from Python via CORBA, XML/RPC or SOAP.

Alternatively, c-jdbc being open-source one could look at the algorithms 
used and create a similar library for Python. I had something like this 
in mind recently :)

> [...] I have looked at SQLRelay, and it does address some, but not all the
> requirements, because there is no mechanism to direct update queries
> transparently to other machines. Off course I want to hide the
> complexity of updating multiple databases from my application. It looks
> as though it can be used with pyPgsql. Is that the case?

No, SQLRelay cannot be used with pyPgSQL. There's, however, a DB-API 
Python library to access a SQLRelay backend. It doesn't have pyPgSQL's 
special features like Unicode, PgResultSets etc. of course.

-- Gerhard