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TreeView Control with MySQL


While I was trying to convert TreeView Control to work with MySQL I encounter an error with concurrent connection using DataReader. The error message was “There is already an open DataReader associated with this Connection which must be closed first”.

Even the Microsoft KB does not help in solving this problem. The workaround on this problem is to create another connection to avoid this error.

After searching the internet for known issues some are reporting that this is a bug in MySQL Connector/Net. But of course some disagree because they said that you cannot create a concurrent connection with DataReader.


In order to run this tutorial successfully you need to import two files included in the zip file. First import Creates.sql, second import Inserts.sql, third import Views.sql using Toad. For more information on the software requirements please read Visual Basic and MySQL article.

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Submitted byAnonymous (not verified)on Thu, 09/24/2009 - 15:05

basically u could not do 2 datareader open in revised your sql statement or stored procedure. ( :) work on me) , anyway there is also called MARS in SQL Server (not in mySQL) that allow you to open multiple datareader. but unfortunately i have no idea how to used MARS ( hehehe! ).

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