email from SQL server are wrong - sql

Question

I am using SQL Server 2008 and am trying to send emails to customers about their overdue ADV returns. There is a 30 day, 45 day and 50 day letter. I have noticed this issue currently on the 30 day and 45 day letters.
I have a query that pulls the right people. For instance on the 30 day letter today it pulled 4 records and they are correct. for instance the data looks like
john item1
david item1
david item2
fred item1
So what is happening is I get 4 emails, but john is missing and david gets 3 emails one of which is a duplicate.
Here is the code for sending the emails
OPEN C1
FETCH NEXT FROM C1
INTO #sronum, #transdate,#item,#desc, #days, #email, #NAME
WHILE ##FETCH_STATUS = 0
BEGIN
FETCH NEXT FROM C1
INTO #sronum, #transdate,#item,#desc,#days, #email, #NAME
set #email = 'internal test email address'
set #subject = 'ADV Return is 30 days past due'
set #body = 'Dear ' + #name + ', </br></br>' + more text
EXEC msdb.dbo.sp_send_dbmail
#recipients = #email
,#Body = #Body
,#subject = #Subject
,#body_format = 'html'
,#exclude_query_output = 1
END
CLOSE C1
DEALLOCATE C1

Answer 1

A bit commented;
OPEN C1
-- Fetch first result and throw it away since next fetch will be done
-- before using the values
FETCH NEXT FROM C1 INTO
#sronum, #transdate,#item,#desc, #days, #email, #NAME
-- If the fetch went well, loop
WHILE ##FETCH_STATUS = 0
BEGIN
-- Fetch the next row and ignore if it went well for now
FETCH NEXT FROM C1 INTO
#sronum, #transdate,#item,#desc,#days, #email, #NAME
set #email = 'internal test email address'
set #subject = 'ADV Return is 30 days past due'
set #body = 'Dear ' + #name + ', </br></br>' + more text
-- Send a mail to the possibly valid address
EXEC msdb.dbo.sp_send_dbmail
#recipients = #email
,#Body = #Body
,#subject = #Subject
,#body_format = 'html'
,#exclude_query_output = 1
-- Jump back to the start of the loop to check if the mail just sent
-- was supposed to be sent.
END
CLOSE C1
DEALLOCATE C1
The simplest fix is to move the second fetch after the email has been sent. That will check if the first result was valid, send a mail, fetch a new row and go back to the validity check to possibly send another mail.