Replace date with datetime or take from date as one day before
<pre lang="SQL">Select
(MonitorData.DesktopGroup.Name) as 'Delivery',sum(MonitorData.DesktopOSDesktopSummary.PeakConcurrentInstanceCount) as 'Total'
from MonitorData.DesktopGroup
join MonitorData.DesktopOSDesktopSummary on MonitorData.DesktopOSDesktopSummary.DesktopGroupId = MonitorData.DesktopGroup.Id
where MonitorData.DesktopOSDesktopSummary.ModifiedDate BETWEEN '2017-07-27 00:00:00.000' AND '2017-07-28 23:59:59.000'
group by MonitorData.DesktopGroup.Name
or
Select
(MonitorData.DesktopGroup.Name) as 'Delivery',sum(MonitorData.DesktopOSDesktopSummary.PeakConcurrentInstanceCount) as 'Total'
from MonitorData.DesktopGroup
join MonitorData.DesktopOSDesktopSummary on MonitorData.DesktopOSDesktopSummary.DesktopGroupId = MonitorData.DesktopGroup.Id
where MonitorData.DesktopOSDesktopSummary.ModifiedDate BETWEEN '2017-07-26' AND '2017-07-28'
group by MonitorData.DesktopGroup.Name