¹ technically, these is not a CMDB table as categories are not CIs in ServiceNow. Use of the available "CMDB" view is recommended for this table.

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Object	Example URL
Categories (Test)	https://yaletest.service-now.com/sc_category_list.do?&sysparm_view=CMDB&CSV
IT Business Services (Test)	https://yaletest.service-now.com/u_it_business_service_list.do?&CSV
IT Provider Services (Test)	https://yaletest.service-now.com/u_it_provider_service_list.do?&CSV
Applications (Test)	https://yaletest.service-now.com/cmdb_ci_appl_list.do?&CSV
Servers (Test)	https://yaletest.service-now.com/cmdb_ci_server_list.do?&CSV

CMDB Schema

Overview

The CMDB is represented in an object-oriented fashion. There are some key points to understand:

Labels are the table and field names seen in the UI. The underlying schema names may differ.
different cmdb_ci_* tables represent different classes of CI. Each class self-identifies via the Class sys_class_name column.
CI classes exhibit a hierarchy:
- cmdb_ci is the base class for CI types. From the systems's perspective, anything in this table or child tables are CIs. So listing all cmdb_ci rows will also show you rows in child tables (e.g. cmdb_ci_appl)
- Child classes are extensions of the parents, so they inherit the parent columns
- Child classes may (and probably will) have their own type-specific columns
For scope purposes, separate classes may have columns of the same name, but belong to the child and not the parent.
relationships have two common types:
- references (many-to-one) - a column that points to another record.
- relationships (many-to-many) - a m2m table which glues many records to many others. The CMDB uses cmdb_rel_ci to do this, though custom m2m tables may exist.

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parent - a GUID (sys_id) of the "parent" record of the relationship
child - a GUID (sys_id) of the "child" record of the relationship
type - the selected relationship type. The semantics of the various types are subject to revision. To start, we are creating a generic "Parent of::Child of" and using that by default.

Schema names underlying table and field labels can be seen in the sys_documentation table.