migrations

ruby
class AddSettingsToAccounts < ActiveRecord::Migration[7.1]
  disable_ddl_transaction!

  def change
    add_column :accounts, :settings, :jsonb, null: false, default: {}

Postgres JSONB Partial Index for Feature Flags

rails postgres jsonb
by codesnips 3 tabs
php
<?php

use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;

Laravel database migrations for schema management

laravel migrations database
by Carlos Mendez 3 tabs
ruby
class CreateUsers < ActiveRecord::Migration[7.1]
  def change
    create_table :users do |t|
      t.string :name, null: false

      # Ciphertext is larger than plaintext, so use text columns.

ActiveRecord Encryption for PII Fields

rails security encryption
by codesnips 4 tabs
ruby
class CreateTags < ActiveRecord::Migration[7.0]
  def change
    create_table :tags do |t|
      t.string :name, null: false
      t.integer :taggings_count, null: false, default: 0
      t.timestamps

Normalize Tags at Write Time

rails activerecord callbacks
by codesnips 3 tabs
ruby
# Create table migration
class CreateUsers < ActiveRecord::Migration[7.0]
  def change
    create_table :users do |t|
      t.string :email, null: false, index: { unique: true }
      t.string :name, null: false

Database migrations and schema management

ruby rails migrations
by Sarah Mitchell 2 tabs
ruby
class AddOptimisticLockingToDocuments < ActiveRecord::Migration[7.1]
  def change
    add_column :documents, :lock_version, :integer, null: false, default: 0
    add_index :documents, :updated_at
  end
end

Optimistic Locking for Collaborative Edits

rails activerecord concurrency
by codesnips 3 tabs
ruby
class AddUniqueIndexToTags < ActiveRecord::Migration[7.1]
  disable_ddl_transaction!

  def up
    execute <<~SQL
      UPDATE tags SET name = LOWER(TRIM(name)) WHERE name IS NOT NULL;

Safer “find or create” with Unique Constraint + Retry

rails activerecord concurrency
by codesnips 3 tabs
ruby
class CreateMaintenanceTasks < ActiveRecord::Migration[7.0]
  def change
    create_table :maintenance_tasks do |t|
      t.string :name, null: false
      t.string :state, null: false, default: "pending"
      t.datetime :started_at

Database-Backed “Run Once” Migrations for Maintenance Tasks

rails migrations background-jobs
by codesnips 3 tabs
ruby
class AddUniqueIndexToInventorySnapshots < ActiveRecord::Migration[7.1]
  disable_ddl_transaction!

  def change
    add_index :inventory_snapshots,
              [:warehouse_id, :sku],

Bulk Upsert with insert_all + Unique Index

rails activerecord postgres
by codesnips 3 tabs
ruby
class AddStatusToPosts < ActiveRecord::Migration[6.1]
  # Use change for automatic rollback
  def change
    # Add column without default to avoid table lock
    add_column :posts, :status, :string

Rails database migrations best practices

rails migrations database
by Maya Patel 3 tabs
sql
CREATE TABLE daily_metrics (
    id          BIGGENERATED ALWAYS AS IDENTITY PRIMARY KEY,
    tenant_id   BIGINT      NOT NULL,
    metric      TEXT        NOT NULL,
    day         DATE        NOT NULL,
    count       BIGINT      NOT NULL DEFAULT 0,

SQL upsert for counters (ON CONFLICT DO UPDATE)

postgres sql concurrency
by codesnips 3 tabs
python
from django.db import migrations


def populate_slugs(apps, schema_editor):
    """Generate slugs for existing posts."""
    Post = apps.get_model('blog', 'Post')

Django database migrations best practices

django python migrations
by Priya Sharma 1 tab