Call Stored Procedure inside a db trigger

Question

Is that possible to call stored procedure inside a db trigger ?
I User this code:
Create Or Replace Trigger Sale.Send_Auto_Email_Trg
After Insert
On Sale.Sale_Technical_Support
--Referencing New As New Old As Old
For Each Row
Declare
Pragma Autonomous_Transaction;
vn_count         Number := 0;
vn_msg           Number;
vv_exec          Varchar2(5000);
Begin
  If Inserting And :New.Ticket_Status = 2 Then
   Begin
    Begin
     Select Count(*)
       Into vn_count
       From Sale_Technical_Support
      Where Sending_Flag = 1
        And Support_Type = 2;
    Exception When No_Data_Found Then
     vn_count := 0;
    End;
    If vn_count >= 1 And :New.Problem_Desc Is Not Null Then
     Technical_Support_Mailing('[email protected]',  -- To
                               '[email protected]',
                               '[email protected]',  -- Bcc
                               '[email protected]',  -- From
                               'رموز وصلاحيات',
                               2);                                                                                          
    End If;
   End;
  End If;
End;
/No errors but the procedure doesn't executed !!!!!

Answer 1

1) If you are using autonomous transactions for anything other that writing log data that you want to preserve even if the triggering transaction fails, you're probably doing something wrong. There is no reason to use an autonomous transaction here.
2) You don't want to send email from a trigger. You don't want to do anything non-transactional in a trigger. Oracle will, for example, rollback and re-execute parts of a statement for write consistency. If you send email in a trigger, you may get multiple emails for a single update. You may also get emails for updates that were never committed. And if the email server happens to be down, your transactions will fail.
3) If you use an autonomous transaction, the trigger will have a completely different transaction context from the parent. So when you query the table within the trigger, you won't be able to see any of the uncommitted changes including the changes that caused the trigger to fire. My guess is that you are assuming that the row that you inserted is visible to the trigger.
Justin