Checking for Previous Table Entries on a Front-End Form? 1

[fbueller]

I am relatively new to ADPs and Access development. I am creating an appl to track industrial shipments. When a truck comes onsite, 2 weights are recorded..an Incoming(full) weight and an Outgoing(empty) weight.

I have a table named SCALE_READINGS to store Incoming/ Outgoing weights for each truck. 1 truck ends up 2 weight entries to form a complete record.

I have not been able to figure out a way to run a query behind the scenes to check the SCALE_READINGS table when a user selects the record button to insert a new entry. I have written a stored procedure accepting the TruckId and WeightType(In/Out) parameters chosen on a form which featurs a SELECT COUNT statement to determine if there is a previous entry of that weight type for a truck. A value of '1' means YES.

But I am not sure how to tie this query which works great when run manually to a hidden control on the main form. I have been experimenting with the different DoCmd options(RunSQL, OpenStoredProcedure, OpenQuery) to no avail.

Can someone give me any pointers? If the returned count is 1, I want to present the user with a MsgBox making sure they want to overwrite the previous record.

Any help would be appreciated!

 

[PHV]

Have you tried the DCount function ?

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ181-2886

 

[fbueller]

The DCount fn() was exactly what I was looking for!! It took me a little while to figure out how to set the criteria according to form parameters, but I got it.

I have been working from what I thought was a great book: MS Office Access 2003 Inside and Out from MS Press. It’s one of those huge monster books with over 1200 pages. I thought it was good, but when I went back and looked there was no mention of the DCount fn().

Is there a website or book that you would recommend to find a complete, indexed view of available procedures and fn() available?

 

[PHV]

I've personally only played with the F2 and F1 keys in VBE.