Darrell Burns
dhb at flsi.com
Sun May 15 16:24:32 CDT 2011
Jim, <<And in regards to your tables, I'd put them in a temp DB and access them via links, then kill the DB when you exit the app. You can create the temp DB easily enough by storing templates for the tables in the current DB and using transferdatabase to create the tables in the temp DB.>> Good suggestion. I'll do that. -DB -----Original Message----- From: accessd-bounces at databaseadvisors.com [mailto:accessd-bounces at databaseadvisors.com] On Behalf Of Jim Dettman Sent: Sunday, May 15, 2011 12:39 PM To: 'Access Developers discussion and problem solving' Subject: Re: [AccessD] Should I use Attachments? << Meaning exactly what you said.>> Hum...guess I don't understand your point; it was a new feature. There was nothing previously there to be compatible with. <<Re: "... the data is compressed" Do you know how it's compressed? More than a Zip?>> I know it is for certain, but I don't know how much. I just know that you can't pull the raw data from the field, but must use import/export commands to get at it. If you user GetChunk on an attachment field, you get data you cannot use. <<Re: "...bloating DB's is a thing of the past" Boy, it hasn't been a thing of the past in my experience. Maybe this is grist for another mill, but I am constantly contending with bloat from reusing tables (in A2007); ie; I have fixed tables bound to subforms that get flushed and refilled each time a tab is clicked.>> I was strictly speaking about storing objects within a DB, not data operations. Nothing has changed there. Deleted space is still not reclaimed until a compact. Bloat from OLE objects was due to a wrapper placed around an object, which often yielded a size that was 2 or 3x the original object size. That no longer exists with the attachment field type. And in regards to your tables, I'd put them in a temp DB and access them via links, then kill the DB when you exit the app. You can create the temp DB easily enough by storing templates for the tables in the current DB and using transferdatabase to create the tables in the temp DB. Jim. -----Original Message----- From: accessd-bounces at databaseadvisors.com [mailto:accessd-bounces at databaseadvisors.com] On Behalf Of Darrell Burns Sent: Sunday, May 15, 2011 11:27 AM To: 'Access Developers discussion and problem solving' Subject: Re: [AccessD] Should I use Attachments? Re: "I'm not sure what you mean by not backward-compatible" Meaning exactly what you said. Re: "... the data is compressed" Do you know how it's compressed? More than a Zip? Re: "...bloating DB's is a thing of the past" Boy, it hasn't been a thing of the past in my experience. Maybe this is grist for another mill, but I am constantly contending with bloat from reusing tables (in A2007); ie; I have fixed tables bound to subforms that get flushed and refilled each time a tab is clicked. Although no more than a few records each, I can watch the file size increase a few kb as I click back and forth. I still have to rely on Compact/Repair to control the bloat. -DB -----Original Message----- From: accessd-bounces at databaseadvisors.com [mailto:accessd-bounces at databaseadvisors.com] On Behalf Of Jim Dettman Sent: Sunday, May 15, 2011 4:26 AM To: 'Access Developers discussion and problem solving' Subject: Re: [AccessD] Should I use Attachments? I'm not sure what you mean by "not backward-compatible". It's a new feature and did not exist in prior versions, so yes, it would not be available in JET (it's an ACE only feature). As far as performance, I have not heard anything in that regard. It's not the same animal as an OLE field; there is no OLE wrapper around the object. And the data is compressed to boot. So bloating DB's is a thing of the past. However because of that, you just can't pull the raw data out and move it or use it in some other way. Also, you still must contend with the ACE DB limit of 2GB. Given all that, I would still do it the traditional way as Rocky said; store a path in the DB and keep everything outside of the DB. Jim. -----Original Message----- From: accessd-bounces at databaseadvisors.com [mailto:accessd-bounces at databaseadvisors.com] On Behalf Of Darrell Burns Sent: Saturday, May 14, 2011 08:33 PM To: 'Access Developers discussion and problem solving' Subject: [AccessD] Should I use Attachments? New subject: my client wants to link PDF documents to records in an Asset table in an A2007 app. The attachment data type is perfect for what I want to do, but I've heard bad things about it. I know one caveat is that it's not backward-compatible. I've also heard that it's a performance drag. (I tried using OLE fields in A2000 a few years ago and quickly abandoned that approach). The Asset table would range from a few hundred to a couple thousand records per client. I'll be deploying the app as a runtime. I'd be interested in hearing the pros & cons of attachments. Thanx, DB -- AccessD mailing list AccessD at databaseadvisors.com http://databaseadvisors.com/mailman/listinfo/accessd Website: http://www.databaseadvisors.com -- AccessD mailing list AccessD at databaseadvisors.com http://databaseadvisors.com/mailman/listinfo/accessd Website: http://www.databaseadvisors.com -- AccessD mailing list AccessD at databaseadvisors.com http://databaseadvisors.com/mailman/listinfo/accessd Website: http://www.databaseadvisors.com -- AccessD mailing list AccessD at databaseadvisors.com http://databaseadvisors.com/mailman/listinfo/accessd Website: http://www.databaseadvisors.com