Comments on: Memory leak with Enterprise Library 4 Data block and Execute Reader

By: Jinu

Jinu — Wed, 14 Dec 2011 08:51:25 +0000

Thanks..I was searching for this…

By: Drew Freyling

Drew Freyling — Fri, 25 Sep 2009 07:42:36 +0000

haha i forgot to use xmlreader :(
Might help if I read the article properly!

By: Drew Freyling

Drew Freyling — Fri, 25 Sep 2009 06:05:06 +0000

I just ran a quick test and it used one connection the entire time and once it was finished it quickly released it. No connection pool overflowing at all?

for (int i = 0; i < 10000; i++)
{
Database database = DatabaseFactory.CreateDatabase("ConnectionString");
using (DbCommand command = database.GetStoredProcCommand("[TestProc]"))
{
using (IDataReader rdr = database.ExecuteReader(command))
{
while (rdr.Read())
{
Console.WriteLine(rdr.GetString(0));
}

// // If you do not explicitly close the connection here, it will leak!
// if (command.Connection.State == ConnectionState.Open)
// {
// command.Connection.Close();
// }
}
}
}

By: Drew Freyling

Drew Freyling — Fri, 25 Sep 2009 05:11:53 +0000

Here is the generated code instead the Repository of the Web Service Software Factory =>
///
/// Find all objects that match the given criteria.
///
/// Type of object used to identify
/// the objects to find.
/// Factory object that can turn the
/// identity object into the appropriate DbCommand.
/// Factory object that can turn the
/// returned result set into a domain object.
/// Object that identifies which items to get.
///
public List Find(
ISelectionFactory selectionFactory,
IDomainObjectFactory domainObjectFactory,
TIdentity identity)
{
List results = new List();

using (DbCommand command = selectionFactory.ConstructSelectCommand(db, identity))
{
using (IDataReader rdr = db.ExecuteReader(command))
{
while (rdr.Read())
{
results.Add(domainObjectFactory.Construct(rdr));
}
}
}
return results;
}

Wouldn’t this do the same?

By: Richard

Richard — Thu, 24 Sep 2009 02:30:42 +0000

I’m not sure Drew, I would imagine they explicitly close connections already.

By: Drew Freyling

Drew Freyling — Wed, 23 Sep 2009 01:25:51 +0000

So this would be a problem with alot of things, including the Web Service Software Factory (Guidance Automation)?

By: Richard

Richard — Mon, 15 Jun 2009 22:12:04 +0000

@Jamison – I’m not sure. The author of the article (http://msdn.microsoft.com/en-us/library/aa175863.aspx) only mentions data readers, but I guess it could extend to other classes that perform similar behaviour. Make a test case to be sure :)

By: Jamison White

Jamison White — Mon, 15 Jun 2009 15:33:59 +0000

Thanks Richard,
This has been an ongoing problem for me, and I think this will fix it. You used a data reader here, but do all dbcommandwrapper’s have this problem?
Jamison White