Quick Start

# Without installing first
npx @flvmnt/pgfence analyze migrations/add-email-verified.sql

# Or after installing locally / globally
pgfence analyze migrations/add-email-verified.sql

migrations/add-email-verified.sql  [HIGH]
  Lock: ACCESS EXCLUSIVE | Blocks: reads+writes+DDL | Risk: HIGH | Rule: add-column-not-null-no-default

┌────┬──────────────────────────────────────────────┬────────────────────┬────────────────┬────────────┬──────────────────────────────────────────────┐
│ #  │ Statement                                    │ Lock Mode          │ Blocks         │ Risk       │ Message                                      │
├────┼──────────────────────────────────────────────┼────────────────────┼────────────────┼────────────┼──────────────────────────────────────────────┤
│ 1  │ ALTER TABLE users ADD COLUMN email_verified  │ ACCESS EXCLUSIVE   │ reads, writes, │ HIGH       │ ADD COLUMN "email_verified" with NOT NULL    │
│    │ BOOLEAN NOT NULL                             │                    │ DDL            │            │ but no DEFAULT...                            │
└────┴──────────────────────────────────────────────┴────────────────────┴────────────────┴────────────┴──────────────────────────────────────────────┘

  Policy Violations:
  ERROR Missing SET lock_timeout
    → Add SET lock_timeout = '2s'; at the start of the migration

  Safe Rewrite Recipes:

  add-column-not-null-no-default: Add nullable column, backfill, then add NOT NULL constraint
    ALTER TABLE users ADD COLUMN IF NOT EXISTS email_verified boolean;
    -- Backfill out-of-band in batches (repeat until 0 rows updated)...
    ALTER TABLE users ADD CONSTRAINT chk_nn CHECK (email_verified IS NOT NULL) NOT VALID;
    ALTER TABLE users VALIDATE CONSTRAINT chk_nn;
    ALTER TABLE users ALTER COLUMN email_verified SET NOT NULL;
    ALTER TABLE users DROP CONSTRAINT chk_nn;

=== Coverage ===
Postgres ruleset: PG14+ (configurable)
Analyzed: 1 statements  |  Unanalyzable: 0  |  Coverage: 100%

# TypeORM
pgfence analyze --format typeorm src/migrations/*.ts

# Prisma
pgfence analyze --format prisma prisma/migrations/**/migration.sql

# Knex
pgfence analyze --format knex migrations/*.ts

# Drizzle
pgfence analyze --format drizzle drizzle/*.sql

# Sequelize
pgfence analyze --format sequelize src/migrations/*.js

# Auto-detect format
pgfence analyze migrations/*

- name: Check migration safety
  run: npx @flvmnt/pgfence analyze --ci --max-risk medium migrations/*.sql