is there a way in SQL server that i can count the items 90 days prior to the inception date and the items 90 days after the inception date. Example:
select
site,
Use:
SELECT t.site,
SUM(CASE WHEN t.date BETWEEN DATEADD(dd, -90, '2009-10-01') AND DATEADD(ss, -1, '2009-10-01') THEN 1 ELSE 0 END) AS numPrior,
SUM(CASE WHEN t.date BETWEEN DATEADD(dd, 1, '2009-10-01') AND DATEADD(dd, 91, '2009-10-01') THEN 1 ELSE 0 END) AS numPost
FROM YOUR_TABLE t
GROUP BY t.site
Tweak the DATEADD function and inception date as you need.
http://msdn.microsoft.com/en-us/library/aa258267(SQL.80).aspx