All tables in the SimpleOne system may be classified by the type of processed data and by their purpose.

Classification by purpose

By purpose, the tables can be divided into:

• System tables – support the operation of the SimpleOne platform. They are supplied by the vendor, and are protected against modification by the end-user. These tables can be distinguished by the sys_ prefix in their system name.
• Application tables are created by the vendor or business solution developer within an application. These tables can be distinguished by the application prefix in their system names. For example, itsm_ prefix is used for all tables related to the ITSM application.
• User tables are used by users in the process of operation of the SimpleOne system. 

Classification by the type of processed data

By the type of processed data, the tables can be divided into:

• Configuration
• Reference
• Transactional
• Journal

Configuration tables

Configuration tables contain records with the information on the current configuration on a SimpleOne platform instance and are used as the primary source of input parameters, determining the operation and functionality of the platform itself and applications developed on its base. For example, the Tables (sys_db_table) contains records with configuration information on all tables of an instance, including itself, as well as on the virtual root table for all tables.

These tables are normally versioned, i.e. they are processed by the version control system.

The configuration tables can be further subdivided into the following subclasses:

• System configuration tables are supplied by the vendor, constitute an integral part of a platform engine, and contain records with directive information for these engines or for the business logic implemented using the platform capabilities. These tables and their columns are protected from modification with special policies (дать ссылку) to prevent users from changing the platform behavior.
  Examples: Business Rules (sys_busines_rule), Columns (sys_db_column), Access Control List (ACL) (sys_security_acl).
  
• Application configuration tables contain records with directive information for the business logic implemented using the platform capabilities within the limits of an application. The application configuration tables supplied by the vendor are protected by special policies as the system configuration tables. The application configuration tables created and modified by the business solution developers for their purposes can be unprotected.
  Examples: Event Rules (itsm_event_rule), Monitoring Rules (itsm_monitoring_rule)

Reference tables

The reference tables contain master data which define the business entities an enterprise is dealing with. Such business entities, depending on the area of activities, may include clients, suppliers, products, services, contracts, invoices, patients, etc. In addition to the information directly describing a business entity, the reference tables describe relations between these entities and hierarchies. For example, for the purposes of finding additional sales opportunities, it may be important to identify explicit and implicit relations between persons.

Examples: Employees (sys_employee), Company (org_company), Content Item (content_item).

The data of the reference table contain reference data, which determine values of specific entities, used when performing transactions within the limits of the whole enterprise. These entities include timezones, countries, languages, etc. The reference data seldom change.

Examples: Timezone пояс (sys_timezome), Language (sys_language).

Transactional tables

The transactional tables contain the data, generated as a result of business transactions, carried out by an enterprise. For example, for the service department of a company it is providing services, registering and processing requests, planning and approving work, notification of final user and responsible person, etc. The transactional systems make a wide use of reference tables when carrying out transactions.

The records of transactional tables are the object of create, read, update, and delete (CRUD) transactions within automated business processes and procedures.

Examples: Tasks (task), Approval (sys_approval).

Journal tables

The journal tables contain data that include historical transaction and reference data. They are used to solving various analytical tasks and making management decisions.

Examples: History (sys_history), Activity Feed Item (sys_activity_feed_item), Main Log (sys_log), Email (sys_email).