Get data for first date and last date

Nancy,

Try this:

;WITH DBSnapshots AS (

SELECT DBName, 
Min(postdate) as OldestGatherDate, 
Max(postDate) as NewestGatherDate
FROM DBGrowthRate
GROUP BY DBName

)

SELECT 
s.DBName,
d1.CurSize as OriginalSize
d1.Gatherdate as OldestGatherdate
d2.CurSize as CurrentSize 
d2.Gatherdate as NewestGatherdate
FROM DBSnapshots s
        JOIN DBGrowthRate d1 ON s.dbname = d1.dbname
                AND s.OldestGatherDate = d1.Gatherdate
        JOIN DBGrowthRate d2 ON s.dbname = d2.dbname
                AND s.NewestGatherDate = d2.Gatherdate