Question

So I’m trying to write a SQL Server Trigger that will call an ASP.Net DLL.

I have got everything talking, but I’m completely stumped that when the triggers fires it can not see the “inserted” table?!?!

Msg 6522, Level 16, State 1, Procedure etrition_train_trigger_clr35, Line 1
A .NET Framework error occurred during execution of user-defined routine or aggregate "etrition_train_trigger_clr35": 
System.Data.SqlClient.SqlException: Invalid object name 'inserted'.
System.Data.SqlClient.SqlException: 
   at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj)
   at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj)
   at System.Data.SqlClient.SqlDataReader.ConsumeMetaData()
   at System.Data.SqlClient.SqlDataReader.get_MetaData()
   at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString)
   at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async)
   at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result)
   at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method)
   at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method)
   at System.Data.SqlClient.SqlCommand.ExecuteReader()
   at CLRTrigger.CLRTrigger.SQLTriggerCall()

Here is my .Net Code. Like I said it fires off when the trigger condition is met, however it can’t see the inserted table for some reason.

public static void SQLTriggerCall()
{
    SqlTriggerContext triggContext = SqlContext.TriggerContext;
    SqlConnection cn = new SqlConnection("Server=vm260101;Database=RT_Training;uid=XXXXXX;pwd=XXXXXXX;Enlist=False;");
    cn.Open();
    SqlCommand sqlComm = cn.CreateCommand();
    SqlPipe sqlP = SqlContext.Pipe;
    SqlDataReader dr;
    sqlComm.CommandText = "SELECT stu_fee_gu, stu_fee_pay_trans_gu, amount from inserted";
    dr = sqlComm.ExecuteReader();
    String stu_fee_gu = "";
    String stu_fee_pay_trans_gu = "";
    float amount = 0;
    while (dr.Read())
    {
        stu_fee_gu = Convert.ToString(dr["stu_fee_gu"]);
        stu_fee_pay_trans_gu = Convert.ToString(dr["stu_fee_pay_trans_gu"]);
        amount = (float)Convert.ToDecimal(dr["amount"]);
    }
    cn.Close();
}

Answer 1

The connection cn that you’ve opened doesn’t share the same context as the trigger. Try using the context connection

See the examples under SqlTriggerContext for usage within a trigger, e.g.:

// Retrieve the connection that the trigger is using.
  using (SqlConnection connection
     = new SqlConnection(@"context connection=true"))
  {
     connection.Open();

     // Get the inserted row.
     command = new SqlCommand(@"SELECT * FROM INSERTED;",
                              connection);

     // Get the user name and real name of the inserted user.
     reader = command.ExecuteReader();
     reader.Read();
     //More...

Of course, the rest of that example is very poor, since it assumes only a single row in inserted. Don’t make that mistake in your own code.