In the select statement I changed the table name where your retrieving the date.

Thanks Again

UPDATE AE SET AE.count_fact = dtCounts.count_fact

FROM #tmp_ar_exception AE INNER JOIN

(

SELECT DISTINCT #tmp_ar_exception.dt_id, COUNT(F_AR_Detail.date_id) AS count_fact FROM #tmp_ar_exception LEFT OUTER JOIN

F_AR_Detail ON #tmp_ar_exception.dt_id = F_AR_Detail.date_id

GROUP BY #tmp_ar_exception.dt_id

) dtCounts on AE.dt_id = dtCounts.dt_id