Inventory Rules fulfill the roles of Detection or Applicability checks in relation to a Managed Software Delivery Policy. They represents a check on an agent computer system and can only return the values of true/false, or fail in the case of an incorrectly written rule. An Inventory Rule is stored as an xml file that the Inventory Rule Management(IRM) agent is able to parse and execute. Each rule is connected with the provider that implements the rule functionality. For example, the IRM smart rules are implemented by the SMF rule provider so when a smart rule is executed on an agent computer the IRM calls the SMF provider functionality to determinate the rule evaluation result. Additionally, an Inventory Rule contains the DataClass attribute that is like a folder for the rules (IRM server cache stores rules by the DataClass). Rule DataClass partitioning was previously used by the Patch Solution (before 7.1) to decrease the number of rules that are posted to the agent. After 7.1, Patch is using its own rule functionality and, as a result, most of the rules currently point to the empty DataClass.
The IRM agent plug-in uses a SQLite database to store the local rule cache. Database file is located under Agents\Inventory Rule Agent\InventoryRuleCache.ibd. The database is not viewable in standard document readers and requires a viewer with SQLite readability. One such tool is SQLite Database Browser. This tool can be found here: sqlitebrowser.sourceforge.net/