Slow_Learner
Sep 24th, 2002, 06:50 AM
I'm working with a dataset with a number of tables that contain unique-constraint fields. The data I'm working with sometimes contains single or double quotes. At first I was testing to see if a given unique already existed in the table before trying to insert it, but I noticed that the single quotes (probably the double quotes too) can cause the .Select method to generate an exception. I wasn't so concerned about that (for my project I just care if the unique stays unique) so as an experiment I tried omitting the .Select and just trying to insert the record anyhow, trusting the exception handler to catch and discard the error.
WOW WAS THAT DUMB! A process that took 1-2 seconds ballooned into 20+ seconds! The overhead caused by generating and discarding the exceptions is many many times worse than rather than testing for the presence of a unique. Possibly this is excruciatingly obvious to an experienced programmer, but this stuff is pretty tough to learn without a teacher. Anyhow I just thought I'd pass this along in case anyone has a similar task.
Now I guess I have to find an alternative to .Select that won't choke on quote marks. Maybe I'll have better luck with DataRowCollection.Find.
Update: .Find works great for enforcing uniqueness, but I wish there was a better way to handle .Select (I have occasions where I need to return multiple records when searching). I have no idea how to phrase a .Select parameter when the value I'm .Selecting against contains a quote mark. :( Anyone have an idea?
Aha! Thank you Mr. Forum Search!
http://www.vbforums.com/showthread.php?s=&threadid=70413&highlight=select+quote+mark
WOW WAS THAT DUMB! A process that took 1-2 seconds ballooned into 20+ seconds! The overhead caused by generating and discarding the exceptions is many many times worse than rather than testing for the presence of a unique. Possibly this is excruciatingly obvious to an experienced programmer, but this stuff is pretty tough to learn without a teacher. Anyhow I just thought I'd pass this along in case anyone has a similar task.
Now I guess I have to find an alternative to .Select that won't choke on quote marks. Maybe I'll have better luck with DataRowCollection.Find.
Update: .Find works great for enforcing uniqueness, but I wish there was a better way to handle .Select (I have occasions where I need to return multiple records when searching). I have no idea how to phrase a .Select parameter when the value I'm .Selecting against contains a quote mark. :( Anyone have an idea?
Aha! Thank you Mr. Forum Search!
http://www.vbforums.com/showthread.php?s=&threadid=70413&highlight=select+quote+mark