Migrations

Migrations allow you to version and evolve your database schema safely.

Creating a Migration

Create a migration file in your migrations directory:

import { Migration } from 'hysteria-orm';

export default class extends Migration {
  async up() {
    this.schema.createTable('users', (table) => {
      table.bigSerial('id').primary();
      table.string('name');
      table.string('email').unique();
      table.integer('age');
      table.boolean('is_active');
      table.timestamp('created_at');
      table.timestamp('updated_at');
    });
  }

  async down() {
    this.schema.dropTable('users');
  }
}

Running Migrations

In order to run typescript migrations, you need have typescript package installed. It's advised to install typescript as a dev dependency and to use typescript migrations only in development. Run migrations using the CLI or programmatically:

npx hysteria run:migrations
yarn hysteria run:migrations

Rolling Back

npx hysteria rollback:migrations
yarn hysteria rollback:migrations

Schema Builder API

• createTable, alterTable, dropTable, renameTable, truncateTable
• Column types: string, integer, bigSerial, boolean, date, jsonb, enum, etc.
• Constraints: primary, unique, references, notNullable, default, etc.

API Reference

createTable

Create a new table with columns and constraints.

schema.createTable('users', (table) => {
  table.bigSerial('id').primary();
  table.string('email').unique();
});

• table (string): Table name
• cb (function): Callback to define columns
• options.ifNotExists (boolean, optional): Only create if not exists

alterTable

Alter an existing table (add/drop/modify columns).

schema.alterTable('users', (table) => {
  table.addColumn('age', 'integer', {
    notNullable: true,
    // other options
  });
});

• table (string): Table name
• cb (function): Callback to define alterations

dropTable

Drop a table.

schema.dropTable('users');

• table (string): Table name
• ifExists (boolean, optional): Only drop if exists

renameTable

Rename a table.

schema.renameTable('old_users', 'users');

• oldtable (string): Current table name
• newtable (string): New table name

truncateTable

Remove all rows from a table.

schema.truncateTable('users');

• table (string): Table name

unique

Add a unique constraint to columns.

schema.unique('users', ['email']);

• table (string): Table name
• columns (string[]): Column names
• constraintName (string, optional): Custom constraint name

Best Practices

• Use one migration per schema change.
• Always provide a down method.
• Test migrations in CI.

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Next: Programmatic Migrations