Re: [ZODB-Dev] RelStorage support to Microsoft SQLServer
On 11/17/2010 11:12 AM, Shane Hathaway wrote: > On 11/17/2010 08:29 AM, Sachin Tekale wrote: >> Hi all, >> I have read that there is a problem to implement MS-SQL adapter for >> Relstorage because the “Two phase commit” feature is not exposed by >> MS-SQL server . > > No, RelStorage does not require two phase commit support from the > database. It turns out that a simple commit lock, which is sufficient > for preventing deadlocks and unreported conflicts. I forgot to finish my mid-sentence thought: "It turns out that a simple commit lock, which nearly all databases support, is sufficient for preventing deadlocks and unreported conflicts." Shane ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] RelStorage support to Microsoft SQLServer
On 11/17/2010 08:29 AM, Sachin Tekale wrote: > Hi all, > I have read that there is a problem to implement MS-SQL adapter for > Relstorage because the “Two phase commit” feature is not exposed by > MS-SQL server . No, RelStorage does not require two phase commit support from the database. It turns out that a simple commit lock, which is sufficient for preventing deadlocks and unreported conflicts. > Is there solution to overcome this problem, Without introducing too many > layers? > Can we use PyMSSQL and ADODB Python extension to implement the > relstorage Adapter for MS-SQL. > Has any one tried this before? > > Are there any other major concerns you would have for developing MS-SQL > adapter component? > > Please point us in right direction on the subject. Using mxODBC is a good start, but you still need SQL designed for MS-SQL, since SQL is only loosely standardized. I could help you out. Email me privately if you are interested. Shane ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] RelStorage support to Microsoft SQLServer
On 17 November 2010 17:05, Laurence Rowe wrote: > On 17 November 2010 16:34, Alan Runyan wrote: >>> I have read that there is a problem to implement MS-SQL adapter for >>> Relstorage because the “Two phase commit” feature is not exposed by >>> MS-SQL server . >> >> unsure about that. probably depends on the client access library. > > At least when I looked at pyodbc/FreeTDS in 2008 FreeTDS did not have > support for the tds packets necessary for joining an XA transaction. > (FreeTDS is the odbc -> SQL Server driver used on unix.) See: > http://article.gmane.org/gmane.comp.db.tds.freetds/9598. I did have > some more information on a SQLAlchemy wiki page but that seems to have > gone now. Found that here: http://www.sqlalchemy.org/trac/wiki/MSSQLTwoPhaseCommit Laurence ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] RelStorage support to Microsoft SQLServer
On 17 November 2010 16:34, Alan Runyan wrote: >> I have read that there is a problem to implement MS-SQL adapter for >> Relstorage because the “Two phase commit” feature is not exposed by >> MS-SQL server . > > unsure about that. probably depends on the client access library. At least when I looked at pyodbc/FreeTDS in 2008 FreeTDS did not have support for the tds packets necessary for joining an XA transaction. (FreeTDS is the odbc -> SQL Server driver used on unix.) See: http://article.gmane.org/gmane.comp.db.tds.freetds/9598. I did have some more information on a SQLAlchemy wiki page but that seems to have gone now. However, two phase commit may not be necessary with the current version of RelStorage - it's not used with PostgreSQL anymore. >> Is there solution to overcome this problem, Without introducing too many >> layers? >> Can we use PyMSSQL and ADODB Python extension to implement the >> relstorage Adapter for MS-SQL. > > i recently had a discussion with some guys about this. i am unsure what > their analysis was. but my opinion: > - adodbapi is not good. > - pymssql i've not used > - pyodbc we used but it doesnt support storedprocs. works ok. > - mxodbc we use and highly recommend. > > yes mxodbc costs money but you have support. i spoke with shane > about this in the past about which library would he probably use if > he were to support mssqlserver and his unresearched/not definitive > answer was mxodbc. mainly because its supported and has been > in production usage for almost a decade. I've used stored procedures with pyodbc: http://code.google.com/p/pyodbc/wiki/StoredProcedures Laurence ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] RelStorage support to Microsoft SQLServer
> I have read that there is a problem to implement MS-SQL adapter for > Relstorage because the “Two phase commit” feature is not exposed by > MS-SQL server . unsure about that. probably depends on the client access library. > Is there solution to overcome this problem, Without introducing too many > layers? > Can we use PyMSSQL and ADODB Python extension to implement the > relstorage Adapter for MS-SQL. i recently had a discussion with some guys about this. i am unsure what their analysis was. but my opinion: - adodbapi is not good. - pymssql i've not used - pyodbc we used but it doesnt support storedprocs. works ok. - mxodbc we use and highly recommend. yes mxodbc costs money but you have support. i spoke with shane about this in the past about which library would he probably use if he were to support mssqlserver and his unresearched/not definitive answer was mxodbc. mainly because its supported and has been in production usage for almost a decade. > Has any one tried this before? no. > Are there any other major concerns you would have for developing MS-SQL > adapter component? shane would be best to answer this. > Please point us in right direction on the subject. many of our customers use mssqlserver; we would be very interested in the outcome. so please keep the zodb mailing list up-to-date with your progress. my suggestion: use mxodbc. involve shane so he can fold it into the main relstorage line in the future. maybe even budget some money to pay him so he has interest in the outcome of the mssql/odbc adapter for relstorage. cheers alan ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
[ZODB-Dev] RelStorage support to Microsoft SQLServer
Hi all, I have read that there is a problem to implement MS-SQL adapter for Relstorage because the “Two phase commit” feature is not exposed by MS-SQL server . Is there solution to overcome this problem, Without introducing too many layers? Can we use PyMSSQL and ADODB Python extension to implement the relstorage Adapter for MS-SQL. Has any one tried this before? Are there any other major concerns you would have for developing MS-SQL adapter component? Please point us in right direction on the subject. Thanks Sachin Tekale -- Sachin Tekale Senior Software Engineer Propylon Ltd. ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
[ZODB-Dev] RelStorage support to Microsoft SQLServer
I have read that there is a problem to implement MS-SQL adapter for Relstorage because the “Two phase commit” feature is not exposed by MS-SQL server . Is there solution to overcome this problem, Without introducing too many layers? Can we use PyMSSQL and ADODB Python extension to implement the relstorage Adapter for MS-SQL. Has any one tried this before? Are there any other major concerns you would have for developing MS-SQL adapter component? Will you help us in developing the MS-SQL adapter for Relstorage? Please point us in right direction on the subject. Thanks Sachin Tekale -- Sachin Tekale Senior Software Engineer Propylon Ltd. ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev