UFN_INVITATION_SENTONMOSTRECENT

        CREATE function dbo.UFN_INVITATION_SENTONMOSTRECENT
        (
            @INVITATIONID uniqueidentifier,
            @INVITEEID uniqueidentifier
        )
        returns datetime
        with execute as caller
        as
        begin
            declare @SENTON datetime;

            select top (1)
                @SENTON = INVITATIONHISTORY.DATECHANGED
            from
                dbo.INVITEE
                left join dbo.INVITEEHISTORY
                    on INVITEE.CONSTITUENTID = INVITEEHISTORY.CONSTITUENTID
                    and INVITEE.EVENTID = INVITEEHISTORY.EVENTID
                left join dbo.INVITATIONHISTORY on INVITEEHISTORY.INVITATIONHISTORYID = INVITATIONHISTORY.ID
                left join dbo.INVITATIONSTATUS on INVITATIONHISTORY.BUSINESSPROCESSSTATUSID = INVITATIONSTATUS.ID
            where
                INVITEE.ID = @INVITEEID
                and INVITATIONSTATUS.PARAMETERSETID = @INVITATIONID

            order by
                INVITATIONHISTORY.DATECHANGED desc;

            return @SENTON;
        end