Configuring Type of Materials (TOMs)

Polaris supports customizable, MARC driven Type of Material (TOM) definitions using a table based configuration model. TOM logic uses a configurable table instead of hard coded rules, allowing libraries to customize existing TOMs and define new ones. Configured TOMs are consistently displayed throughout Polaris and returned via Polaris API (PAPI).

TOM definitions are stored in a configurable Type of Material Rules table in Polaris System Administration (web-based), where libraries can add, customize, reorder, and delete TOMs.

MARC Expression Language (MEL) defines all TOM logic for Polaris defaults and custom TOMs. MEL is a compact boolean predicate language that evaluates MARC 21 records for TOM classification, faceting, searching, and display behavior. For more information, see MARC Expression Language (MEL).

Because TOM rules are used across multiple Polaris services and applications, updates are not fully applied until the overnight synchronization and indexing processes complete and the relevant services and client applications are restarted.

The sections below explain how to configure and use TOMs:

• Configure Type of Material Rules Table

• Required Steps for TOM Changes

• Type of Material (TOM) Rules

• MARC Expression Language (MEL)