Re: DataReader Behavior

[Simon Rigby]

Hi Oscar,

1. By all means, while looping you can get values from the current record to insert or update, but only by adding a seperate command object in the loop and inserting or updating through it. Data Reader is readonly / forward only.

2. Yes. But they must be on seperate connections. The DataReader has full control of a connection and the connection can not be user for anything else until the attached reader is closed.

3. I've not noticed anything wrong with the MySqlDataReader. It performs as I would expect if the table is empty or contains rows. I use them frequently with SQL Server/MSDE (SqlDataReader) with no problems.

4. I must admit I have not used this property before. My usual course of action for testing for an empty reader is as follows.

Try
while dr.read
'Do Something
end while
Catch ex as InvalidOperationException
'Do the stuff you need to do for an empty reader
Finally
dr.Close()
End Try

No suggesting that this is the best way to do it (I must admit I'd never noticed the HasRows Property) but might be worth a try to see if it gives you the same problems.

Maybe drop a full code example of what your trying to do (including anything happening within the loop).

Hope this helps.

Simon Rigby