Schema updates

This section describes how to update the squid schema in development and in production. All database changes are applied through migration files located at db/migrations. The squid-typeorm-migration(1) tool provides several commands to drive the process.

It is all TypeORM under the hood.

# Connect to database, analyze its state and generate migration to match the target schema.
# The target schema is derived from entity classes generated earlier.
# Don't forget to compile your entity classes beforehand!
npx squid-typeorm-migration generate

# Create template file for custom database changes
npx squid-typeorm-migration create

# Apply database migrations from `db/migrations`
npx squid-typeorm-migration apply

# Revert the last performed migration
npx squid-typeorm-migration revert         

Drop-create

In most cases the simplest way to update the schema is to drop the database and regenerate the migrations from scratch.

1. Update schema.graphql

2. Regenerate the model classes and build the squid with

make codegen
make build

3. Recreate the database and remove the old migrations

make down
rm -rf db/migrations/*.js
make up

4. Create the new database migration

npx squid-typeorm-migration generate

5. Apply the database migration

make migrate

Updating a deployed squid schema

In some rare cases it is possible to update the schema without dropping the database and restarting the squid from a blank state. The most important case is adding an index to an entity field. More complex changes are usually not feasible.

1. Update schema.graphql

For example, add an index

2. Regenerate the model classes

make codegen
make build

3. Create new database migration

Make sure the local database is running.

npx squid-typeorm-migration generate

4. Apply the database migration

Inspect the new migration in db/migrations and apply it:

make migrate

5. Update the squid in Aquairum

If the squid is deployed to Aquarium, update the deployed version.