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Losing database connections with dropdown menus

redouard asked
Last Modified: 2013-11-26
I created an vb.net aspx page with three dropdown menus. All three dropdown menus are connected to a table in SQL. When the page is load dropdown #1 is populated with two database selections to choose from. Depending on what database you select dropdown #2 and #3 will be populated with different data. The problem, I'm having is when the page is loaded and select an item in dropdown menu #2 or/and #3 and select the submit button, I get an error message like so:

Exception Details: System.Data.SqlClient.SqlException: INSERT statement conflicted with COLUMN FOREIGN KEY constraint 'User_FK00'. The conflict occurred in database 'OMNIVISOR_PLUS_HCMB', table 'PatientGroup', column 'PatientGroupID'. Cannot insert the value NULL into column 'UserID', table 'OMNIVISOR_PLUS_HCMB.dbo.Professional'; column does not allow nulls. INSERT fails. The statement has been terminated. The statement has been terminated.

After doing it serveral time, I figured out that when the page is loaded , the items  in the dropdowns are connected to the SQL database. But once I select another items from the dropdowns, I lose connections to the SQL database. How can I prevent this from happening. I attempted to use Page.IsPostBack but it doesn't seem the fix the problem.

Any ideas? Help!
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This looks like a completely different issue.  It looks like you are trying to insert a record into a table that is missing the required UserID field.  Unless one of the dropdown contains the UserID, the dropdowns are not likely the problem.


I've tested it and can reproduce the problem at will. It seems that when I called the page and select the database, it automatically populate the dropdown menus with the first records in the tables. The insert works at this point. The insert fails when I change the records to another record (or item) selected in the tables from dropdown menus #2 or/and #3.  I think I'm losing the the data bind when another item is selected after the initial page load

OK, I see.

So what you are doing is loading the drop downs on initial load of the page and re-loading #2 and #3 when something changes in #1 or #2.  Is this correct?


Yes that's what I'm doing. Make sense?
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