Transition Tree (TT)
A highly detailed action roadmap using 'Current Reality + Action -> New Reality' triplets to ensure execution precision.
π― What Problem It Solves
For complex operations (e.g., server migrations, events), checklists fail to explain how the environment changes after each step, leading to confusion when things go wrong.
π§ Thinking Logic & Core Concepts
TT uses strict chronological steps. Each step has: 1. Current Reality (current state), 2. Action (what to do), and 3. New Reality (the result, which becomes the next step's base).
π Newbie Step-by-Step Guide
- Start & End: Place starting state at the bottom and goal state at the top.
- Define First Step: Connect Current Reality and Action to create a New Reality.
- Progress Step-by-Step: Treat the New Reality as the base for the next action, repeating until the goal is reached.
π‘ Classic Example
[Database Zero-Downtime Migration Case]
- Starting State: Legacy database is active, new instance is ready but empty.
- Action 1: Put legacy DB in read-only mode and export data.
- New Reality 1: Legacy DB has no writes, backup file is created.
- Action 2: Copy and restore backup to the new database.
- New Reality 2: New DB has all history; legacy DB is ready to retire.