Backup restore site collection sharepoint is the mostly requested task for administrator. As an admin, you should know how to backup sharepoint site collection. When you need to migrate site collection from one environemnt to another environent Example Production to QA mostly, we follow the sharepoint back up restore method. It can be sharepoint content database backup restore method or only backup and restore site using powershell method.
For Particular Requirement, client want to dedicate a database for a single site collection. When we create a site collection from central admin, site is placed automatically in any available content database. To prevent any other sites to be created on the particular content database, We can set maximum number of site collection on particular content database. read full article for details.
Partial Index Reset of a single content source. SharePoint will rebuild the index for these sources, when the next full crawl is started.