Changing Site Collection Primary Administrator in SharePoint Using SQL SERVER

If you  want to Change Site Collection Primary administrator Using SQL Server

update [ContentDataBaseName].[dbo].[UserInfo] set tp_Login='Domain\UserName', tp_Title='UserName' where tp_ID=UserID and tp_SiteID='SiteCollectionID'


If you  want to Change Site Collection Secondary administrator Using SQL Server

update [ContentDataBaseName].[dbo].[AllSites] set OwnerID=UserID , SecondaryContactID=UserID where id='SiteCollectionID'