Solved

Table Definition - Set lookup values based on another field in table

Posted on 2012-04-10
9
602 Views
Last Modified: 2012-04-11
I am working on an Access 2010 database (32 bit, accdb). Within this database I am attempting to create a dynamic data validation process, wherein the user can identify fields in tables they want validated, and define what they want those fields validated against.
I have two tables in this database listing the tables in the database that will be validated plus the table(s) that will be used for validation, and all of the fields in these selected tables (tblDdTable and tblDdField, respectively).
I am now creating a new table named tblDdRules. One of the fields in this new table is "TableName". This field is defined with a combobox lookup which queries the table names in tblDdTable. The next field is "FieldName". I would like to define a combobox lookup which queries tblDdField using the value in the prior field "TableName" as the key.
I know I can do this on a form. Is it possible to do this within the table definition itself?
0
Comment
Question by:shambalad
  • 6
  • 3
9 Comments
 
LVL 42

Accepted Solution

by:
dqmq earned 500 total points
Comment Utility
This field is defined with a combobox lookup which queries the table names in tblDdTable.

Yes, Access supports that, but gives you grief in the long run.  Not recommended.  You can create a form for maintaining the table in a couple of clicks.

Also, you do not want both a fk reference to tblDdTable and tblDdField.   Only to tblDdField.



Is it possible to do this within the table definition itself?

I don't think so and that would not be a good idea, either.

You really don't want to
0
 
LVL 7

Author Comment

by:shambalad
Comment Utility
OK - I hear you on the 'bad idea' bit, but humor me. You say it's possible.  
I am attaching a small database with the three tables mentioned in the first post.
Here is an image of the lookup defined for the TableName field. How would I set up the query for the FieldName lookup?
Image 1Lookup-Question.accdb
0
 
LVL 7

Author Closing Comment

by:shambalad
Comment Utility
OK - I didn't ask the right question. I don't really want to know whether this is a good or bad idea. I want to know how it's done. I'll open up a new question and rephrase.
0
 
LVL 42

Expert Comment

by:dqmq
Comment Utility
Must be some EE glitch, but I've responded twice with a detailed explanation that has found it's way to the bit bucket. Don't have time to write it up again.  FWIW, thanks for including the db, that helps a bunch for understanding your question.

Here's the shortened version.

I meant to say that technique is supported for the SourceTable column, but not for the SourceField column constrained by the SourceTable column as you want.

I've attached my design.   As per your request, I did not remove the column look ups, but improved them as best I could.

Finally, I also cleaned up the foreign key relationship issues that I suspected.  As a result, you may find it acceptable to maintain rules by drilling down from the tblDdTables or tblDdFields rather than lookups from tblRules.
Lookup-Question.accdb
0
Free Trending Threat Insights Every Day

Enhance your security with threat intelligence from the web. Get trending threat insights on hackers, exploits, and suspicious IP addresses delivered to your inbox with our free Cyber Daily.

 
LVL 7

Author Comment

by:shambalad
Comment Utility
Thank you for getting back to me on this. I have attached an image of the dropdown for the FieldName combobox. Note how it is not being filtered for the value of the TableName field. This is what I was getting at. I would want to see only the fields for the tblElement table.
image 1
0
 
LVL 7

Author Comment

by:shambalad
Comment Utility
After closing this question. I opened up a new one:
http://www.experts-exchange.com/Microsoft/Development/MS_Access/Q_27670885
I do try to avoid opening multiple questions on the same topic. Anyway, I closed out the other one.
I appreciate your help on this. I hear you all loud and clear on the merits of this approach, but at this point I simply want to know how this is done.
0
 
LVL 7

Author Comment

by:shambalad
Comment Utility
FWIW:
Some years ago I was supporting multiple Access databases for a major Health insurer. The individual who originally created the databases had extensively used lookups in the table definitions, so I know just how much of a major PITA they can be.
I still want to know how I can create a lookup which filters based on the value of another field in the table.
0
 
LVL 42

Expert Comment

by:dqmq
Comment Utility
Within a table definition, there is no way to design a lookup rowsource that is "filtered" based on the value entered (but not yet updated) to another column of the same row.
0
 
LVL 7

Author Comment

by:shambalad
Comment Utility
That's what I thought. In truth, that is what I was really trying to get at in my original question. Thank you for taking the time to follow up on this. I appreciate your help.
Regards,
Todd
0

Featured Post

Backup Your Microsoft Windows Server®

Backup all your Microsoft Windows Server – on-premises, in remote locations, in private and hybrid clouds. Your entire Windows Server will be backed up in one easy step with patented, block-level disk imaging. We achieve RTOs (recovery time objectives) as low as 15 seconds.

Join & Write a Comment

It took me quite some time to sort out all the different properties of combo and list boxes available from Visual Basic at run-time. Not that the documentation is lacking: the help pages are quite thorough and well written. The problem was rather wh…
Regardless of which version on MS Access you are using, one of the harder data-entry forms to create is one where most data from previous entries needs to be appended to new records, especially when there are numerous fields and records involved.  W…
Get people started with the utilization of class modules. Class modules can be a powerful tool in Microsoft Access. They allow you to create self-contained objects that encapsulate functionality. They can easily hide the complexity of a process from…
Show developers how to use a criteria form to limit the data that appears on an Access report. It is a common requirement that users can specify the criteria for a report at runtime. The easiest way to accomplish this is using a criteria form that a…

772 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

10 Experts available now in Live!

Get 1:1 Help Now