Child primary server delete but still show in console

Recently we have faced one problem that after deletes one Primary server from SCCM hierarchy, the server still is showing on SCCM console. We have checked the logs, but no hope. After that I am going to use preinst command, now the magic is that when I am going to use Del job it always delete job one by one, but when I used the Del site command to show me the error like “not a known site” (ID have admin access which is used for run the print command).  After searching the solution over the net I have found one solution, which is not recommended, but works for me. 

Solution: Delete few data from SCCM DB where the Primary server attaches previously. And then wait for a couple of minutes and then refresh the console.  Favorable outcome............:)

The commands are:

--DELETE FROM SysResList WHERE SiteCode = 'XXX' 

--DELETE FROM SiteBoundaryADSite WHERE SiteCode = 'XXX' 

--DELETE FROM SiteBoundaryIPSubnet WHERE SiteCode = 'XXX' 

--DELETE FROM SiteControl WHERE SiteCode = 'XXX' 

--DELETE FROM SiteControlNotification WHERE SiteCode = 'XXX' 

--DELETE FROM Sites WHERE SiteCode = 'XXX' 

--DELETE FROM Sites_DATA WHERE SiteCode = 'XXX' 

--DELETE FROM SiteWork WHERE SiteCode = 'XXX' 

--DELETE FROM PkgServers WHERE sitecode = 'XXX' 

--DELETE FROM PkgStatus WHERE sitecode = 'XXX'

Help link : http://social.technet.microsoft.com/Forums/systemcenter/en-US/7eb67737-30f4-4b4a-a9d4-914a0150b03e/remove-child-objects-with-preinstexe?forum=configmgrsetup