MultiThreading error: There is already an open DataReader associated with this Connection which must be closed first

Question

I have a Parallel.Foreach loop

var options = new ParallelOptions();
options.MaxDegreeOfParallelism = 1;
Parallel.ForEach(urlTable.AsEnumerable(),drow =>
{         


        

Answer 1

You're using the same connection at the same time.

Do you have several thread ? Because it seems that 2 threads use the same connection to concurrently make a call.