@netka-entrust/drizzle-db-patch

Generate SQL patches for PostgreSQL databases backed by Drizzle ORM:

• generate — diff a Drizzle schema module against a live database and emit a SQL patch (CREATE TABLE, ADD COLUMN, CREATE INDEX, ADD FOREIGN KEY, ADD UNIQUE, plus commented DROPs for orphans). Read-only against the target DB.
• seed — dry-run a seed orchestrator and capture every emitted INSERT as inline SQL. The DB client is stubbed; no real connection is opened.

Peer-depends on drizzle-orm (>= 0.30) and postgres (>= 3.4). Node ≥ 20.

Install

pnpm add -D @netkasystem/drizzle-db-patch

Published as a public package on npmjs.com — no authentication required.

CLI

generate — schema vs live DB

DATABASE_URL="postgres://user:pass@host:5432/db" \
  pnpm drizzle-db-patch generate \
    --schema ./src/db/schema \
    --out ./scripts/db-patch.sql

Options:

| Flag | Default | Description | | ---------------- | --------------- | ----------------------------------------------------------------------------------------------------------- | | --schema | (required) | Path to a module that exports the Drizzle schema (typically a barrel file that re-exports every pgTable). | | --database-url | $DATABASE_URL | Postgres connection URL. Read-only access is sufficient. | | --out | db-patch.sql | Output file. |

Output sections (each wrapped in BEGIN/COMMIT):

1. Missing tables — CREATE TABLE IF NOT EXISTS
2. Missing columns — ALTER TABLE ADD COLUMN IF NOT EXISTS
3. Orphan tables — commented DROP TABLE (manual review)
4. Orphan columns — commented ALTER TABLE DROP COLUMN (manual review)
5. Missing indexes — CREATE INDEX IF NOT EXISTS
6. Missing foreign keys — ALTER TABLE ADD CONSTRAINT ... FOREIGN KEY
7. Missing unique constraints — ALTER TABLE ADD CONSTRAINT ... UNIQUE

seed — dry-run a seed orchestrator

The seed command needs an entrypoint module that wires your application's DB client to the stub provided by this package. Create a file like scripts/seed-patch-entry.ts:

import type { GenerateSeedPatchOptions } from "@netkasystem/drizzle-db-patch";

const opts: GenerateSeedPatchOptions = {
  installStub: async (stub) => {
    // Replace the real postgres-js client with the stub. The exact wiring
    // depends on how your app exposes the client.
    const dbModule = (await import("@/db")) as {
      db: { session: { client: unknown } };
    };
    dbModule.db.session.client = stub;
  },
  runSeed: async () => {
    // Intercept process.exit so the seed runner doesn't kill our process
    // before we write the patch.
    const origExit = process.exit.bind(process);
    let exited = false;
    (process as unknown as { exit: (code?: number) => void }).exit = (() => {
      exited = true;
    }) as never;
    try {
      await import("@/db/seed/seed");
      const start = Date.now();
      while (!exited) {
        if (Date.now() - start > 300_000) {
          throw new Error("Timed out waiting for seed to finish (5 min).");
        }
        await new Promise((r) => setTimeout(r, 100));
      }
    } finally {
      process.exit = origExit;
    }
  },
  header: ["Source: src/db/seed (dry-run, no DB connection)"],
};

export default opts;

Then run:

pnpm drizzle-db-patch seed \
  --entry ./scripts/seed-patch-entry.ts \
  --out ./scripts/seed-patch.sql

The CLI loads the entry module, calls installStub(stub), runs runSeed(), and writes captured INSERTs to --out. SELECTs are answered from rows inserted earlier in the same run (best-effort), so seeds that chain INSERT ... RETURNING -> SELECT can usually complete.

Programmatic API

import {
  generateDbPatch,
  generateSeedPatch,
} from "@netkasystem/drizzle-db-patch";
import * as schema from "./src/db/schema";

const { sql, stats } = await generateDbPatch({
  schema,
  databaseUrl: process.env.DATABASE_URL!,
});

See src/index.ts for full type definitions.

Publishing (manual)

The package is not auto-published. Bump the version and publish from a local workstation:

cd packages/drizzle-db-patch

# 1. Bump version
npm version patch  # or minor / major

# 2. Build
pnpm build

# 3. Login to npmjs.com (once per machine)
npm login

# 4. Publish
npm publish --registry=https://registry.npmjs.org

The package's publishConfig.registry points at https://registry.npmjs.org. The --registry flag overrides any scope mapping in your global ~/.npmrc (e.g. if @netkasystem is mapped to GitHub Packages there).

After publishing, commit the version bump:

git add packages/drizzle-db-patch/package.json
git commit -m "chore(drizzle-db-patch): publish vX.Y.Z"