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Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints.

Last Modified: 2012-05-10
Using Visual Studio with MySQL.

In my XSD dataset I created a query. It runs perfect. I can preview the data fine.

In my BLL I wrote code (see below) to retrieve the query results and I'm getting...
Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints.

Why would previewing the data work but in code it fails?

Any ideas?
Using db As New dsDemoTableAdapters.DemoTableAdapter
     Dim dt As New DataTable
     dt = db.GetDemo(DemoId) ' ERROR HAPPENS HERE

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are you using same id to for query and preview?

if not then please check if the query is returning null on some fields in join or duplicate data.


the param (DemoId) is the exact same

i can literally see the data results when i preview the query in the xsd dataset

this is strange...i don't see any reason for this...


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