SQL 2012 Trigger bulk insert lock

Question

Hi
I have built a proc which basically captures some invalid codes and what I would like to do is use a trigger to fire an email everytime this the table receives information .
;WITH MatchesCTE ( SK_Partial, Matchcode ) AS  
(SELECT 1, '1234')
SELECT * INTO match FROM MatchesCTE
ALTER TRIGGER EmailInavildPartials1
   ON  [dbo].[match]
   AFTER INSERT
AS
BEGIN
    -- SET NOCOUNT ON added to prevent extra result sets from
    -- interfering with SELECT statements.
    IF  (@@rowcount > 1)
    SET NOCOUNT ON;  
    --SELECT GETDATE() ;
    EXEC Send_email_Invalid_Partials1
   END
ALTER PROCEDURE [dbo].[Send_email_Invalid_Partials1]
  AS
  DECLARE @p_body as nvarchar(max), @p_subject as nvarchar(max)
 DECLARE @p_recipients as nvarchar(max), @p_profile_name as nvarchar(max), @p_query as nvarchar(max),
 @p_subject_date as nvarchar(max), @fileName as nvarchar(max)
SET @p_profile_name = N'DEV'
 SET @p_recipients = N'ROBERT@BLAH;'  
 Select @p_subject_date = (select DATENAME (weekday, getdate ()))+ ' ' + substring (convert(varchar,getdate(),12), 5,2) +'/' +  substring (convert(varchar,getdate(),12), 3,2)+ '/' +
   substring (convert(varchar,getdate(),12), 1,2)
 SET @filename = 'INVALID MATCH CODES ' + CONVERT(CHAR(8),GETDATE(),112)+ '.csv'
 SET @p_subject = @p_subject_date + N' INVALID MATCH CODES'
  SET @p_body = 'Please see the invaild Partials List.'
SET @p_query = 'SET NOCOUNT ON;Select * FROM DATABASE..match '
 EXEC msdb.dbo.sp_send_dbmail
   @profile_name = @p_profile_name,
   @recipients = @p_recipients,
   @body = @p_body,
   @body_format = 'HTML',
   @subject = @p_subject,
   @query = @p_query,
   @attach_query_result_as_file = 1,
  @importance = 'High',
  @query_attachment_filename =@filename,
  @query_result_separator = ',',
  @query_result_no_padding = 1
you''ll need to change
@p_profile_name
@p_recipients
@p_query
when you then run the following
INSERT INTO match
SELECT 1,'1234'
UNION
SELECT 1, '5678'
It locks.    Is there any way around this ?  Any help would be great
Thanks

Answer 1

While I can debate the wisdom of this approach in general, as well as the selectivity of your logic with respect to the trigger, the rows inserted, the contents of the entire table - I won't. 
The short story is that this approach will not work.  Your trigger fires within the context of an insert (presumably - perhaps a merge) statement that inserts some unknown number of rows into the target table.  Your trigger logic will then execute
a procedure if more than one (but not one or zero rows) is inserted.  Your procedure will then attempt to execute a query against the same table and attempt to dump ALL rows in the table into a file for the email.  This "dumping" executes in a different
process - hence the blocking. 
Is it correct that your procedure will send the email with an attachment of ALL rows, not just the inserted ones (but ignore the insertion of just one row)?  I can't say.  It would be unusual but stranger things have been done.   To get
around that you can use a locking hint as suggested - but that may not be what you desire depending on other factors (is anything else manipulating the contents of the table while this process is running? Are you certain of that answer after evaluating the
range of possibilities?). 
Perhaps the best approach is to use a very different one.  It appears that you insert rows into the table for a single purpose.  So why not just turn that process into the one that does the notification?