On-Call Scheduling

"Who is on call for the database team?" is one question and four tables. Answering it by guessing at table names is how agents end up querying sys_user_group.manager and reporting the wrong person.

The chain

sys_user_group          the team being covered
   └── cmn_rota          a rotation on that group ("Database — primary")
        ├── cmn_schedule the hours the rotation covers, and its TIME ZONE
        └── cmn_rota_roster   a rotation pattern: weekly, 7 days, starting <date>
             └── cmn_rota_member   one person, with a from/to window
                  └── sys_user

Read it as: a group has rotations, a rotation has rosters, a roster has members. The roster is the pattern (rotate weekly, one week each). The member row is one person's turn — it carries from and to as glide_date, and member referencing sys_user.