Eureka!

1. When working with datareaders and stored procedures, and your stored procedure returns a paramter value, you must close the datareader before you can access the parameter value. Microsoft says its not a bug, but missing functionality is just as bad as erroneous funcitonality. So: BUG!
2. You can call .ExecuteScalar on queries that return multiple rows (for some reason, eventhough it makes no sense), however, it will only return the first field of the first row.
3. You can bind datareaders to web objects when in ASP.NET, however, you can only bind datareaders to datasets, data tables, and data views when working in VB.NET.
4. You must ‘prime’ a datareader before accessing its content, like so:

   While reader.Read()[...]End While

5. When retrieving data from datareaders using the various get methods, only the SQL data type get methods allow for NULL values. Using the get methods uses less overhead, since the data is returned as that explicit type and not as an object.
6. Multiple selects can be executed at the same time using a single data reader. This can be usefull for minimizing resource usage when initializing data when opening an application or loading a web app. Consider the following (note reader.NextResult(), which moves to the next SQL statement in the datareader results):

   comm.CommandText = "SELECT * FROM customers;SELECT * FROM products"reader = comm.ExecuteReaderWhile reader.Read()   [...]End WhileIf (reader.NextResult()) Then   While reader.Read()       [...]   End WhileEnd If

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