Information for all packages installed on a system is kept in the installation software database. There is an entry for every object in a package, with information such as the component name, where it resides, and its type. An entry contains a record of the package to which a component belongs; other packages that might reference the component; and information such as path name, where the component resides and the component type. Entries are added and removed automatically by the pkgadd and pkgrm commands. You can view the information in the database by using the pkgchk and the pkginfo commands.
Two types of information are associated with each package component. The attribute information describes the component itself. For example, the component's access permissions, owner ID, and group ID are attribute information. The content information describes the contents of the component, such as file size and time of last modification.
The installation software database keeps track of the package status. A package can be either fully installed (it has successfully completed the installation process), or partially installed (it did not successfully complete the installation process).
When a package is partially installed, portions of a package may have been installed before installation was terminated; thus, part of the package is installed, and recorded in the database, and part is not. When you reinstall the package, you are prompted to start at the point where installation stopped because the pkgadd command can access the database and detect which portions have already been installed. You can also remove the portions that have been installed, based on the information in the installation software database using the pkgrm command.