freshyo/apps/migrator/README.md

Migrator

Data-only migration tool between Postgres and SQLite using Drizzle.

What it does

• Copies data from source to target
• Does NOT create or alter tables
• Overwrites target data if any rows exist (via DELETE FROM in dependency-safe order)

Requirements

• Tables must already exist on the target database
• Schema must match the backend Drizzle schemas

Usage

Run from repo root:

bun --cwd apps/migrator run migrate --from postgres --to sqlite --source "<PG_URL>" --target "<SQLITE_PATH>"

bun --cwd apps/migrator run migrate --from sqlite --to postgres --source "<SQLITE_PATH>" --target "<PG_URL>"

Flags

• --from: postgres or sqlite
• --to: postgres or sqlite
• --source: Postgres connection string or SQLite file path
• --target: Postgres connection string or SQLite file path
• --batch: optional batch size (default: 500)

Examples

bun --cwd apps/migrator run migrate \
  --from postgres \
  --to sqlite \
  --source "postgres://user:pass@host:5432/db" \
  --target "./sqlite.db"

bun --cwd apps/migrator run migrate \
  --from sqlite \
  --to postgres \
  --source "./sqlite.db" \
  --target "postgres://user:pass@host:5432/db" \
  --batch 1000

Notes

• IDs are copied as-is to preserve relationships.
• For Postgres targets, sequences may need manual reset after import.