Concerning SignalR and SQL Dependency, is it true that the Query Notification can't use aggregate function like count(*)?
Do one have another way or an idea for create query that contain aggregate function ?
Yes, this is the solution if you want to use an aggregate function like COUNT(*)
with SqlDependency
.
First, in your repository, you will still use a SELECT
query. But in the reader, you just count the rows of data when the reader executes the command. Something like this:
int count = 0;
command = new SqlCommand(
@"select Edolpuz_DB.dbo.TABEL_KONFIRMASI_PEMBAYARAN.ID_BUKTI_PEMBAYARAN " +
@"from Edolpuz_DB.dbo.TABEL_KONFIRMASI_PEMBAYARAN " +
@"where Edolpuz_DB.dbo.TABEL_KONFIRMASI_PEMBAYARAN.IS_NEW = @room",
connect);
command.Parameters.AddWithValue("room", true);
try
{
command.Notification = null;
SqlDependency dependency = new SqlDependency(command);
dependency.OnChange += new OnChangeEventHandler(dependency_OnChange);
if (connect.State == ConnectionState.Open)
connect.Close();
connect.Open();
reader = command.ExecuteReader();
while (reader.Read())
{
count++;
}
return count;
}
catch { return 0;}
finally { connect.Close(); }