Re: [Zope3-dev] Re: [Zope3-Users] ODBC database adapter for Zope3?
Stephan Richter wrote: Oh :-( That sucks. Is there a DBAPI sig for python that we should be talking to about getting that fixed? There is a sig and we could try. But I have *very* little hope that such a proposal would come to fruition. Most applications don't really care about supporting many DB backends. Waaagh :'( 2. Advanced DA implementations support much more datatype conversion than the default database connection package. Yes, but it's inconsistency between DAs on this front that causes problems... Well, the Python DB-API is even worse and does not even try to specify type returns. I agree, maybe we should create a recommendation for Zope 3 DB adapters. *nods* For example, a good DB adapter should always ensure that all datetimes have pytz timezones associated with them. Exactly, which is why that kind of stuff should be in a central place. What happens if a DA DOESN'T do this when someone is expecting it to? (the other common problematic type is that of an SQL NULL) Well, I would love to see a draft on a Zope 3 DA standardization. And I'd love to write one, but I still need to get to grips with the basics of Zope 3 first ;-) Gimme a poke in a month or two! cheers, Chris -- Simplistix - Content Management, Zope Python Consulting - http://www.simplistix.co.uk ___ Zope3-dev mailing list Zope3-dev@zope.org Unsub: http://mail.zope.org/mailman/options/zope3-dev/archive%40mail-archive.com
Re: [Zope3-dev] Re: [Zope3-Users] ODBC database adapter for Zope3?
Benji York wrote: I guess my comments come from seeing lots of different Zope 2 DAs where all the boilerplate of the DA, as opposed to the DB, has been copied between different DAs, and often implemented with varying degrees of incompetence and lack of maintenance ;-) Perhaps a standard adapter for DB-API connection objects? Yeah, I've often dreamed of writing just such a thing for Zope 2 ;-) cheers, Chris -- Simplistix - Content Management, Zope Python Consulting - http://www.simplistix.co.uk ___ Zope3-dev mailing list Zope3-dev@zope.org Unsub: http://mail.zope.org/mailman/options/zope3-dev/archive%40mail-archive.com
Re: [Zope3-dev] Re: [Zope3-Users] ODBC database adapter for Zope3?
Stephan Richter wrote: 1. Parse the DSN to the various DB package formats. One of the big problems of Python's DB API is that it does not specify a unified connection mechanism, while Zope 3 does, which is a very good thing. Oh :-( That sucks. Is there a DBAPI sig for python that we should be talking to about getting that fixed? 2. Advanced DA implementations support much more datatype conversion than the default database connection package. Yes, but it's inconsistency between DAs on this front that causes problems... For example, a good DB adapter should always ensure that all datetimes have pytz timezones associated with them. Exactly, which is why that kind of stuff should be in a central place. What happens if a DA DOESN'T do this when someone is expecting it to? (the other common problematic type is that of an SQL NULL) This in particular is a functionality a generic Python library cannot provide, since Python does not commit to a particular timezone implementation. ...more's the pity ;-) That said, surely it'd be a good thing if all this stuff was in one place for Zope 3? cheers, Chris -- Simplistix - Content Management, Zope Python Consulting - http://www.simplistix.co.uk ___ Zope3-dev mailing list Zope3-dev@zope.org Unsub: http://mail.zope.org/mailman/options/zope3-dev/archive%40mail-archive.com
Re: [Zope3-dev] Re: [Zope3-Users] ODBC database adapter for Zope3?
Stephan Richter wrote: On Wednesday 07 September 2005 08:41, Chris Withers wrote: I know Zope 2 has the bizarre need for a dual Zope DA and Python DB set of things, but do we have to support this pattern in Zope 3? Is there any reason the Zope 3 RBD machinery can't just work with ANY Python DBAPI 2.0 (or whatever..) compatible database library? Yes, we have the need. We need the wrapper to correctly handle our transactions, so that if a RDB transaction is aborted, the ZODB/Zope transaction should also be aborted, etc. OK, that's all well and good, but are you saying that Python's DBAPI doesn't have generic transaction hooks? If it doesn't, that seems like a deficiency that should be addressed in Python with a PEP. If it does, then why don't we use those? I guess my comments come from seeing lots of different Zope 2 DAs where all the boilerplate of the DA, as opposed to the DB, has been copied between different DAs, and often implemented with varying degrees of incompetence and lack of maintenance ;-) If we can get all that stuff in one place, then we have a much better chance of making it as good as it should be, AND we make it possible to use any relational database which has a python library, rather than having ot wait for some poor unsuspecting code monkey to try and write the DA... Chris -- Simplistix - Content Management, Zope Python Consulting - http://www.simplistix.co.uk ___ Zope3-dev mailing list Zope3-dev@zope.org Unsub: http://mail.zope.org/mailman/options/zope3-dev/archive%40mail-archive.com
Re: [Zope3-dev] Re: [Zope3-Users] ODBC database adapter for Zope3?
On Thursday 08 September 2005 06:04, Chris Withers wrote: Is there any reason the Zope 3 RBD machinery can't just work with ANY Python DBAPI 2.0 (or whatever..) compatible database library? Yes, we have the need. We need the wrapper to correctly handle our transactions, so that if a RDB transaction is aborted, the ZODB/Zope transaction should also be aborted, etc. Here are a couple more reasons: 1. Parse the DSN to the various DB package formats. One of the big problems of Python's DB API is that it does not specify a unified connection mechanism, while Zope 3 does, which is a very good thing. 2. Advanced DA implementations support much more datatype conversion than the default database connection package. This is particularly visible for the PstGreSQL DB Adapter. For example, a good DB adapter should always ensure that all datetimes have pytz timezones associated with them. This in particular is a functionality a generic Python library cannot provide, since Python does not commit to a particular timezone implementation. Regards, Stephan -- Stephan Richter CBU Physics Chemistry (B.S.) / Tufts Physics (Ph.D. student) Web2k - Web Software Design, Development and Training ___ Zope3-dev mailing list Zope3-dev@zope.org Unsub: http://mail.zope.org/mailman/options/zope3-dev/archive%40mail-archive.com
Re: [Zope3-dev] Re: [Zope3-Users] ODBC database adapter for Zope3?
On Thursday 08 September 2005 06:04, Chris Withers wrote: If we can get all that stuff in one place, then we have a much better chance of making it as good as it should be, AND we make it possible to use any relational database which has a python library, rather than having ot wait for some poor unsuspecting code monkey to try and write the DA... A very simplistic DA is easy; you basically only have to write a function that uses the DSN value to construct connection arguments for a particular DB package. If you make advanced use of the DB, you also want to register type conversions. Regards, Stephan -- Stephan Richter CBU Physics Chemistry (B.S.) / Tufts Physics (Ph.D. student) Web2k - Web Software Design, Development and Training ___ Zope3-dev mailing list Zope3-dev@zope.org Unsub: http://mail.zope.org/mailman/options/zope3-dev/archive%40mail-archive.com
Re: [Zope3-dev] Re: [Zope3-Users] ODBC database adapter for Zope3?
Chris Withers wrote: I guess my comments come from seeing lots of different Zope 2 DAs where all the boilerplate of the DA, as opposed to the DB, has been copied between different DAs, and often implemented with varying degrees of incompetence and lack of maintenance ;-) Perhaps a standard adapter for DB-API connection objects? -- Benji York Senior Software Engineer Zope Corporation ___ Zope3-dev mailing list Zope3-dev@zope.org Unsub: http://mail.zope.org/mailman/options/zope3-dev/archive%40mail-archive.com
Re: [Zope3-dev] Re: [Zope3-Users] ODBC database adapter for Zope3?
On Wednesday 07 September 2005 08:41, Chris Withers wrote: I know Zope 2 has the bizarre need for a dual Zope DA and Python DB set of things, but do we have to support this pattern in Zope 3? Is there any reason the Zope 3 RBD machinery can't just work with ANY Python DBAPI 2.0 (or whatever..) compatible database library? Yes, we have the need. We need the wrapper to correctly handle our transactions, so that if a RDB transaction is aborted, the ZODB/Zope transaction should also be aborted, etc. Regards, Stephan -- Stephan Richter CBU Physics Chemistry (B.S.) / Tufts Physics (Ph.D. student) Web2k - Web Software Design, Development and Training ___ Zope3-dev mailing list Zope3-dev@zope.org Unsub: http://mail.zope.org/mailman/options/zope3-dev/archive%40mail-archive.com
