Querying / searching package database
Search for a string in package name and package description
pacman -Ss string1 string2 ...
Search in already installed packages
pacman -Qs string1 string2 ...
Display extensive information about a given package
pacman -Si <package_name>
Display extensive information about local package
pacman -Qi <package_name>
List all packages no longer required as dependencies (orphans):
pacman -Qdt
List all packages explicitly installed and not required as dependencies:
pacman -Qet
Install packages
pacman -S <package-name1> <package-name2> ...
Upgrading packages
Upgrade all packages, full-system upgrade
pacman -Syu
Removing Packages
Remove a single package without removing it's dependencies
pacman -R <package_name>
Remove a package and its dependencies which are not required by any other installed package
pacman -Rs <package_name>
Remove a package, its dependencies and all the packages that depend on the target package. Care needed, can potentially remove everything.
pacman -Rsc <package_name>
Remove a package, which is required by another package, without removing the dependent package
pacman -Rdd <package_name>
Remove not needed packages, by chaining commands
pacman -Rns $(pacman -Qdtq)
Pacman's created extra config files and backups for the system can be removed with
pacman -Rn
Cache cleaning
Remove all the cached packages that are not currently installed, and the unused sync databases, execute:
pacman -Sc
Remove all files from the cache, use the clean switch twice, this is the most aggressive approach and will leave nothing in the cache directory:
pacman -Scc
Flags
-S, --sync : Syncs the package repositories.