Plan expand-contract schema migration

Prompt that plans expand-contract schema migration with dual-write and a safe contract phase. Paste it into an AI tool of your choice, which then plans expand-contract schema migration.

Topic: Apps & prototypes
Type: Prompt
Level: Intermediate
Time: about 15 min

Results depend on the tool, the model and what you enter.

Result preview

Example: written by our editors, not real AI output.

Change: rename user.email → user.mail Expand: add mail, dual-write both Readers: API v2 first, BI last Contract: drop email when read=0 for 7 d Abort: if dual-write lag > 2 min

Fill in

What you type stays in this browser window. We store and send nothing.

ChangeWhat changes?

ReadersWho reads?

WritersWho writes?

Your prompt

Help me plan an expand-contract schema migration.
Change: [Change]
Readers: [Readers]
Writers: [Writers]
Steps: 1. State the old and new shape and who breaks if both are not supported. 2. Expand: add new fields or tables without removing old ones. 3. Dual-write or dual-read with a clear switch order. 4. Verify lagging consumers before contract. 5. Contract: remove old fields only with a rollback path. 6. Write a timeline and abort rule.
Output: expand steps, dual phase, contract steps, verification and abort rule.

Take particular care to expand first, dual-write, verify, then contract only when unused.

Before you answer, check: Are all instructions met? If key information is missing or a placeholder in square brackets is still in the text, ask instead of guessing. Mark assumptions as assumptions.

This is an instruction for an AI, not the result itself.

Where this prompt works

These AI tools are a good fit for this prompt:

How to use it

Fill in the fields or tap a suggestion. Leave out names, addresses and other personal data.
Copy the finished prompt into an AI tool of your choice.
Paste schema diff and consumer list, without production rows.

Why does this work?

Dropping the old column before every reader moves is a cutover, not expand-contract. Expand first.

Tips

Keep a feature flag or config for dual-read until metrics prove the old path is idle.

You may use our prompts freely, including at work. Please do not republish them as your own collection. We give no warranty for AI results; check them yourself. Terms of use

Plan expand-contract schema migration

Result preview

Fill in

Your prompt

Where this prompt works

How to use it

Why does this work?

Tips

Also a good fit

Choose pagination for an API list New

Write an API reference people can use right away New

Plan a throttled data backfill New