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Entity Framework : There is already an open DataReader associated with this Command

Recently working on an application with entity framework 4.1 When I was retrieving data and updating data with same data context I was getting following error. It was working fine on another machine but on mine it was giving this error.

There is already an open DataReader associated with this Command.

After digging into the problem for some time I have found that I have not opened multiple active result set in my connection string. So what was happening when I retrieved data with entity framework there was an already opened data reader with that and after that I was updating data so we all know that an data reader is always have connected to particular connection. So it was not allowing me to update the data.
So I have added following attribute to my connection string.

“MultipleActiveResultSets=True”

Then I again test above scenario and it was working fine. It’s very easy. Hope you like it. Stay tuned for more..

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