ATS and CRM Data Architecture · Lesson 1

Model entities and relationships

Course overview · 4 min reading + 12 min practice, estimated

Principles and method

Separate people, organisations, contacts, vacancies, applications and commercial opportunities. One person may have several applications, and one organisation may have several contacts and searches. Storing all of these in a single row creates duplication and contradictory updates. Use stable identifiers rather than names as keys. Define which relationships are one-to-many or many-to-many in plain language. Keep historical relationships distinct from current status. The model should support actual recruitment questions without forcing every workflow into a free-text note.

Worked example

A candidate applies for two roles. Their contact details belong to the person record, while interview stage and decision belong to each application. Rejecting one application must not mark the person rejected everywhere.

Put it into practice

Draw six entities and their relationships for a fictional agency.

Use fictional information and keep your work in your own notes.

Compare your approach: self-review guidance

Include person-to-application and organisation-to-vacancy relationships. Explain where role-specific notes belong. Avoid using an email address as an immutable identity because addresses can change or be shared.

Download the course workbook

Sources and further reading

Original Academy teaching and fictional examples. These references provide context, not endorsement. Edition 2026.09; updated 2026-09-24.

How our learning is designed