Roz Clarke
roz.clarke at donnslaw.co.uk
Tue Jan 25 03:53:13 CST 2005
Cheers Jim Tom is researching your method now and may well be in touch :) Roz -----Original Message----- From: Jim Lawrence [mailto:accessd at shaw.ca] Sent: 25 January 2005 05:36 To: 'Access Developers discussion and problem solving' Subject: RE: [AccessD] Data from Informix to Access - dirty reads? Hi Roz: I worked with Informix about ten to fifteen years ago. It seemed like a good product but that is maybe because I was also using their DOS product, SmartWare to connect to their Unix DB... and they were the only show in town. The problems you are talking about were issues then. At a risk of sounding ignorant, I would recommend an ADO-OLE, recordset, MDE combination. Had over sixty users building reports in this method and the bloat was there but very manageable... only compressed the MDB once a month whether it needed it or not. I placed a simple copy of the method used on the DBA web site. See: http://www.databaseadvisors.com/newletters/newsletter112003/0311UnboundRepor ts.htm The trick is to have an original report temp table used it to clone all the user's tables. Each user & base table name is used to create a new source for the report which is then substituted for the report's source. It is also very fast... 50 thousand records in a few seconds. This process worked so well for me, in a pinch that I never bothered upgrading. If you decide to go this method, drop a request on the list and I can supply all the info you need. HTH Jim -----Original Message----- From: accessd-bounces at databaseadvisors.com [mailto:accessd-bounces at databaseadvisors.com] On Behalf Of Roz Clarke Sent: Monday, January 24, 2005 7:23 AM To: 'Access Developers discussion and problem solving' Subject: [AccessD] Data from Informix to Access - dirty reads? Hi all We have a bit of a problem with getting data out of our Informix server since we recently turned on transaction logging for replication. When extracting data with an Access XP MDE using pass-through queries, Access locks entire tables in the Informix database, which causes transaction errors and makes the Informix database scarily unstable. Our Informix suppliers told us that the way to avoid these locking issues was to set the connection to 'dirty read' before running the SQL. However, Access cannot execute 2 statements in a pass-through query and it does not hold the connection open between the execution of 1 statement and the next. Thus when the query is processed the 'dirty read' setting is no longer in effect. We have been racking our brains trying to come up with a workaround. Some further options that we have considered are: * Stick the data in a temp table in Informix. This is no good because the temp table is destroyed automatically when the connection is closed and there's no way to make it persist long enough to bind it to a report. * Use a view in Informix. This is no good because views in Informix cannot be set read-only. * Create a permanent table in Informix and destroy it when finished with it. This is far from ideal because Informix does not support SELECT INTO and therefore a table would have to be explicitly constructed with names columns etc. We really need the system to be flexible so that the queries can be easily changed. * Use an ADO recordset. This is a PITA because you cannot bind a report to a recordset in an MDE and we cannot build the report on the fly - we are a Terminal Services site so we will have up to 20 users in one FE. * Create a table in Access and destroy it when finished with it. Can't think of a better way to induce bloating... Has anyone faced this kind of problem before? Any bright ideas? Our foreheads are starting to bleed... TIA Roz (and Tom) -- AccessD mailing list AccessD at databaseadvisors.com http://databaseadvisors.com/mailman/listinfo/accessd Website: http://www.databaseadvisors.com -------------- next part -------------- The contents of this message and any attachments are the property of Donns Solicitors and are intended for the confidential use of the named recipient only. They may be legally privileged and should not be communicated to, or relied upon, by any other party without our written consent. If you are not the addressee, please notify us immediately so that we can make arrangements for its return. You should not show this e-mail to any person or take copies as you may be committing a criminal or civil offence for which you may be liable. The statement and opinions expressed in this e-mail message are those of the writer, and do not necessarily represent that of Donns Solicitors. Although any files attached to this e-mail will have been checked with virus protection software prior to transmission, you should carry out your own virus check before opening any attachment. Donns Solicitors does not accept any liability for any damage or loss which may be caused by software viruses...