yum install multiple packages at once fail to rollback

I am working ton installing multiple rpm packages at once.
So, i mention all of them in one yum command. now the scene is,

There are rpm packages such that dependencies of one package is in that rpm's list but dependencies for another package is missing.

1. Will it install one package and reject other? Or it won't install any package at all? What will be the return codes?
2. If it installs one and rejects other then how can i rollback that installed package?
   All i want is, either install all packages or don't install any but don't do partial install (installing one and failing other). If yum has any such scene of partial install then it should be improved to complete install or complete fail rather than partial installing. If yum allows partial instaling then it should have rollback option in the same line to disable partial installing. To avoid partial installing, yum can do all dependencies and other check of those multiple rpm packages before going to install them. If yum already has this feature then sorry, i couldn't find the document.