PostgreSQL Ado support

[wimpleshapers]

Using the latest Npgsql Ado driver, I get an exception when performing a query. The error occurs when the function:

AdoTemplate.Execute<T>(ICommandCallback<T> action)

invokes

T result = action.DoInCommand((DbCommand)command);

The error says the cast to 'DbCommand' is illegal. This makes sense, since the Npgsql driver's implementation of the command object simply implements IDbCommand, and does not extend DbCommand. I was able to correct the problem by changing methods in QueryCallback<T> and ICommandCallback<T> accept IDbCommand instead.

Is this the corrrect action to take, or is the Npgsql library expected to implement DbCommand instead.

Thanks.

[Bruno Baia]

Hi,

This is an known issue :
Spring.Data sometimes uses DbCommand instead of IDbCommand (http://opensource.atlassian.com/projects/spring/browse/SPRNET-552)


Bruno

[Mark Pollack]

Hi,
Yea, we have to provide a signature that has just IDbCommand instead of DbCommand. I'd like to find a way to support both without having to duplicate lots of code, as it is much more convenient to use the parameter class obtained from DbCommand than IDbCommand...
Mark

[Mark Pollack]

Hi,
I have added a new interface and delegate for those providers that do not inherit from the DbCommand base class. They are the interface
public interface IDbCommandCallback<T>
{
T DoInCommand(IDbCommand command);
}
and the delegate
public delegate T IDbCommandDelegate<T>(IDbCommand command);
A few internal classes were using the versions based on DbCommand and those were retro-fitted to use the new version. I still need to go back and clean things up a bit, buy you should be fine for now. It was wrong to assume all .NET 2.0 providers would inherit from the base class, not sure how I got that in my head. Anyway, try it out.

Cheers,
Mark