How do I install the Database Migration skill?

Run npx skillmds@latest add agulli/database-migration in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Database Migration safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Database Migration?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Database Migration free to use?

Yes. Installing skills from SkillMD is free. This skill is licensed under MIT.

Who published Database Migration?

agulli (@agulli) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Database Migration by agulli — Agent Skill

Name: Database Migration
Author: agulli

File contents

Clarification Gates

Before executing any migration, you must have clear answers to all of the following. If any is missing or ambiguous, STOP and ask. Do not infer from filenames, branch names, or previous conversation context.

Environment: local / staging / production?
Backup confirmed: Has a database backup been taken in the last 24 hours?
Migration scope: Is this a new column/table, or does it modify/drop existing data?

An agent that guesses the environment and gets it wrong has just migrated the wrong database. Ask first.

Process

Identify the migration tool. Check the project for:
- alembic.ini → Alembic (SQLAlchemy)
- manage.py → Django migrations
- prisma/schema.prisma → Prisma If none are found, ask the user which tool to use. Do not guess.
Generate the migration.
- Alembic: alembic revision --autogenerate -m "description"
- Django: python manage.py makemigrations
- Prisma: npx prisma migrate dev --name description
Review the generated migration file. Read the entire file. Check for:
- Columns being dropped (STOP and ask the user)
- Table renames (STOP and ask the user)
- Non-nullable columns added without defaults (this will fail on non-empty tables)
Dry run. If the tool supports it:
- Alembic: alembic upgrade head --sql (generates SQL without executing)
- Django: python manage.py sqlmigrate <app> <migration_number>
Apply the migration only after reviewing the dry run output.

Verify. Query the database schema directly to confirm the change took effect:

-- PostgreSQL
SELECT column_name, data_type FROM information_schema.columns WHERE table_name = 'target_table';
-- SQLite
PRAGMA table_info(target_table);

Rationalizations

Excuse	Rebuttal
"It's just an ADD COLUMN, I'll skip the review"	Schema locks can occur even on simple additions. Always review.
"The autogenerated migration looks correct"	Autogenerate guesses. It sometimes generates DROP + CREATE instead of ALTER. Read the file.
"I'll just run it — we can roll back"	Not all migrations are reversible. Dropping a column destroys data permanently.

Verification

Migration file was read in full before applying
No columns were dropped without explicit user approval
Database schema was queried after migration to confirm the change
"The command succeeded" is NOT accepted as sufficient evidence

---name: database-migrationdescription: Safely run database schema migrations. Use when asked to update database schema, add columns, create tables, run alembic, or apply Django migrations.license: MIT---## Clarification GatesBefore executing any migration, you must have clear answers to all of the following. If any is missing or ambiguous, STOP and ask. Do not infer from filenames, branch names, or previous conversation context.- **Environment:** local / staging / production?- **Backup confirmed:** Has a database backup been taken in the last 24 hours?- **Migration scope:** Is this a new column/table, or does it modify/drop existing data?An agent that guesses the environment and gets it wrong has just migrated the wrong database. Ask first.## Process1. **Identify the migration tool.** Check the project for: - `alembic.ini` → Alembic (SQLAlchemy) - `manage.py` → Django migrations - `prisma/schema.prisma` → Prisma If none are found, ask the user which tool to use. Do not guess.2. **Generate the migration.** - Alembic: `alembic revision --autogenerate -m "description"` - Django: `python manage.py makemigrations` - Prisma: `npx prisma migrate dev --name description`3. **Review the generated migration file.** Read the entire file. Check for: - Columns being dropped (STOP and ask the user) - Table renames (STOP and ask the user) - Non-nullable columns added without defaults (this will fail on non-empty tables)4. **Dry run.** If the tool supports it: - Alembic: `alembic upgrade head --sql` (generates SQL without executing) - Django: `python manage.py sqlmigrate <app> <migration_number>`5. **Apply the migration** only after reviewing the dry run output.6. **Verify.** Query the database schema directly to confirm the change took effect: ```sql -- PostgreSQL SELECT column_name, data_type FROM information_schema.columns WHERE table_name = 'target_table'; -- SQLite PRAGMA table_info(target_table); ```## Rationalizations| Excuse | Rebuttal ||--------|----------|| "It's just an ADD COLUMN, I'll skip the review" | Schema locks can occur even on simple additions. Always review. || "The autogenerated migration looks correct" | Autogenerate guesses. It sometimes generates DROP + CREATE instead of ALTER. Read the file. || "I'll just run it — we can roll back" | Not all migrations are reversible. Dropping a column destroys data permanently. |## Verification- [ ] Migration file was read in full before applying- [ ] No columns were dropped without explicit user approval- [ ] Database schema was queried after migration to confirm the change- [ ] "The command succeeded" is NOT accepted as sufficient evidence

Frequently asked questions

Database Migration