Truncate is not the correct usage. Try this:
round((
select avg(cdate("update_date") - cdate("begin_date"))
from "Service_Time_DMC" A, "Progress_Note_View_dmc" B,
"Progress_Note" C
where A."consumer_service_ID" = B."consumer_service_ID" and
B."progress_note_ID" = C."progress_note_ID" and
A."last_name" = "Service_Time_DMC"."last_name"
),0)
If it doesn't accept the cdate, try opening a new report and adding the above to a command that looks like this:
Select
round((
select avg(cdate("update_date") - cdate("begin_date"))
from "Service_Time_DMC" A, "Progress_Note_View_dmc" B,
"Progress_Note" C
where A."consumer_service_ID" = B."consumer_service_ID" and
B."progress_note_ID" = C."progress_note_ID" and
A."last_name" = "Service_Time_DMC"."last_name"
),0) "Ave", "Service_Time_DMC"."last_name"
From (("SC_Production"."dbo"."Service_Time_DMC" "Service_Time_DMC" INNER JOIN
"SC_Production"."dbo"."Consumer_Service_View" "Consumer_Service_View" ON "Service_Time_DMC"."consumer_service_ID"="Consumer_Service_View"."consumer_service_ID") LEFT OUTER JOIN
"SC_Production"."dbo"."Progress_Note_View_dmc" "Progress_Note_View_dmc" ON "Service_Time_DMC"."consumer_service_ID"="Progress_Note_View_dmc"."consumer_service_ID") LEFT OUTER JOIN
"SC_Production"."dbo"."Progress_Note" "Progress_Note" ON "Progress_Note_View_dmc"."progress_note_ID"="Progress_Note"."progress_note_ID"
WHERE
NOT ("Service_Time_DMC"."service_code"='120' OR "Service_Time_DMC"."service_code"='170' OR "Service_Time_DMC"."service_code"='202' OR "Service_Time_DMC"."service_code"='226' OR "Service_Time_DMC"."service_code"='238' OR "Service_Time_DMC"."service_code"='239' OR "Service_Time_DMC"."service_code"='240' OR "Service_Time_DMC"."service_code"='420' OR "Service_Time_DMC"."service_code"='475' OR "Service_Time_DMC"."service_code"='530' OR "Service_Time_DMC"."service_code"='620' OR "Service_Time_DMC"."service_code"='649' OR "Service_Time_DMC"."service_code"='651' OR "Service_Time_DMC"."service_code"='683' OR "Service_Time_DMC"."service_code"='686' OR "Service_Time_DMC"."service_code"='687' OR "Service_Time_DMC"."service_code"='688' OR "Service_Time_DMC"."service_code"='690' OR "Service_Time_DMC"."service_code"='696' OR "Service_Time_DMC"."service_code"='697' OR "Service_Time_DMC"."service_code"='699' OR "Service_Time_DMC"."service_code"='816') AND NOT ("Service_Time_DMC"."last_name"='AFC DAYS' OR "Service_Time_DMC"."last_name"='COMMUNITY LIVING SUPPORTS' OR "Service_Time_DMC"."last_name"='CONNECTIONS' OR "Service_Time_DMC"."last_name"='Contracted' OR "Service_Time_DMC"."last_name"='INGERSOLL' OR "Service_Time_DMC"."last_name"='INPATIENT DAY' OR "Service_Time_DMC"."last_name"='KUBLIN' OR "Service_Time_DMC"."last_name"='MERCER' OR "Service_Time_DMC"."last_name"='MOARC SERVICE PROVIDER' OR "Service_Time_DMC"."last_name"='NICKISSON' OR "Service_Time_DMC"."last_name"='Respite' OR "Service_Time_DMC"."last_name"='THARMAR') AND ("Service_Time_DMC"."begin_date">={ts '2008-09-01 00:00:00'} AND "Service_Time_DMC"."begin_date"<{ts '2008-10-01 00:00:00'})
ORDER BY "Service_Time_DMC"."last_name", "Service_Time_DMC"."begin_date"
If this works, you can link it to your other tables on the name field.
-LB