[AccessD] OLEDB vs ODBC

Gustav Brock Gustav at cactus.dk
Fri Apr 29 06:59:33 CDT 2005


Hi Jim

I forgot an important parameter: resolution.

20K is achieved with 150 dpi which is just enough for a clearly
readable image. 100 dpi will exclude fine print, while 300 dpi delivers
close to photo copy (Xerox) quality.

/gustav

>>> Jdemarco at hudsonhealthplan.org 04/29 1:47 pm >>>
That makes sense because we tested with 8 1/2 by 11" docs.  Maybe our
developer is not using the correct compression.

Thanks,

Jim D.

-----Original Message-----
From: accessd-bounces at databaseadvisors.com 
[mailto:accessd-bounces at databaseadvisors.com]On Behalf Of Gustav Brock
Sent: Friday, April 29, 2005 4:58 AM
To: accessd at databaseadvisors.com 
Subject: RE: [AccessD] OLEDB vs ODBC


Hi Jim

20K will fit a Letter or A4 sized b/w average document in TIFF with
max
compression (CCITT Group 4 Fax compression).

/gustav


>>> Jdemarco at hudsonhealthplan.org 04/28 9:42 pm >>>
We had security issues as well since we're scanning personal
documentation (birth certs, ssn's, etc.) which is how we came to store
the docs as BLOBs also.

I didn't write the app but was heavily involved in the architecture. 
We used a consulting firm to create a scanning component that saves
scanned docs to the BLOB.  Until yesterday I was of the belief that we
we not storing the entire BLOB but now it seems we are.  I'm assuming
that by "entire BLOB" you mean TIFF (or whatever file format you
choose)
header and extraneous data.  The consultant had tested the component
and
assured us that each BLOB would max at approx. 20K but using the
DATALENGTH function James Barash sent me I see that they are quite a
bit
larger than expected.

Is that what you meant?

Jim D.

-----Original Message-----
From: accessd-bounces at databaseadvisors.com 
[mailto:accessd-bounces at databaseadvisors.com]On Behalf Of Francisco
Tapia
Sent: Thursday, April 28, 2005 2:15 PM
To: Access Developers discussion and problem solving
Subject: Re: [AccessD] OLEDB vs ODBC


I don't know... 

While on this topic.... one of the department managers wants to begin 
archiving photo's with calls received in our customer support center.
the FE is an Access ADP, and generally i'm against storing images
inside DBs
and would rather "upload" the image to a location on the server and
serve it up via Access but I'd need to restrict the folder for
uploading
so that users couldn't use that as their personal drive either...

what method are you using Jim or do you Upload the entire BLOB into
the
db?


On 4/28/05, Jim DeMarco <Jdemarco at hudsonhealthplan.org> wrote:
> 
> Here's a good one for you. M$ has long been telling us to use OLEDB
via 
> ADO to access our SQL data. We've been doing just that and in
researching an 
> issue where some BLOB image data is pegging our server CPUs when
uploading 
> via remote network connections I found a KB article that mentions
that there 
> is a bug in the way OLEDB handles large amounts of BLOB data and that
the 
> ODBC drivers should be used instead.
> 
> My question: Our application (thankfully) uses an n-tier architecture
and 
> all the data access is done via centralized components. I know using
ODBC 
> will require modding the connect string. Once we've got a connection
to the 
> database via ODBC will our existing ADO OLEDB code break? AFAIK we're
using 
> connection objects, recordsets and command objects. Is there a lot of
SQL 
> specificity in the way we would access these objects using OLEDB?
> 
> TIA
> 
> Jim DeMarco
> Director of Application Development
> Hudson Health Plan




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