From a data model perspective which Table is the base class for the configuration management database?

Base Item [cmdb_base_item] is a separate table used for asset and CI linking, not the root base class of the CMDB hierarchy.

Configuration Item [cmdb_ci] is a widely used parent table but it extends [cmdb], making it a child of the actual base class rather than the base class itself.

In ServiceNow's CMDB data model, the Base Configuration Item table [cmdb] is the root table from which all other CMDB classes inherit. The commonly referenced Configuration Item [cmdb_ci] table is actually a child of [cmdb], making [cmdb] the foundational base class for the entire configuration management database hierarchy.

Asset [alm_asset] belongs to the Asset Management data model and is a separate hierarchy from the CMDB, not its base class.