migrations

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
php
<?php

use App\Http\Controllers\DocumentsController;
use Illuminate\Support\Facades\Route;

Route::middleware('auth')->group(function () {

Soft Deletes with a Trash View and Restore Route in Laravel

laravel eloquent soft-deletes
by codesnips 4 tabs
ruby
class CreateIdempotencyKeys < ActiveRecord::Migration[7.1]
  def change
    create_table :idempotency_keys do |t|
      t.string :key, null: false
      t.string :request_path, null: false
      t.datetime :locked_at

Idempotent Form Submissions in Rails with an Idempotency-Key Column and before_action Guard

rails idempotency postgres
by codesnips 4 tabs
ruby
class CreateAuditLogs < ActiveRecord::Migration[7.1]
  def change
    create_table :audit_logs do |t|
      t.references :auditable, polymorphic: true, null: false
      t.references :user, null: true, foreign_key: true
      t.string :action, null: false

Rails Audit Log for Model Changes Using ActiveRecord Callbacks

rails activerecord callbacks
by codesnips 4 tabs
python
from django.db import models
from django.utils.text import slugify


class Article(models.Model):
    title = models.CharField(max_length=200)

Auto-Generate Unique Slugs in Django with a pre_save Signal and Model Method

django signals slugs
by codesnips 3 tabs
php
<?php

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

Recording an Audit Trail of Model Changes with a Laravel Observer

laravel eloquent observers
by codesnips 4 tabs
python
from django.db import models
from django.utils import timezone


class WebhookEvent(models.Model):
    class Status(models.TextChoices):

Idempotent Stripe Webhook Handling in Django with a Unique Event-ID Constraint

django webhooks idempotency
by codesnips 3 tabs
ruby
class CreateCustomerRevenueSummaries < ActiveRecord::Migration[7.0]
  def change
    create_view :customer_revenue_summaries, materialized: true, version: 1

    add_index :customer_revenue_summaries,
              :customer_id,

Database Views for Read Models

rails postgres performance
by codesnips 4 tabs
sql
CREATE TABLE subscriptions (
    id                  BIGGENERATED ALWAYS AS IDENTITY PRIMARY KEY,
    customer_id         BIGINT       NOT NULL,
    plan_code           TEXT         NOT NULL,
    status              TEXT         NOT NULL DEFAULT 'active',
    current_period_end  TIMESTAMPTZ  NOT NULL,

Partial index for “active” rows in Postgres

postgres performance sql
by codesnips 3 tabs
sql
-- Step 1: add the column nullable, no default.
-- Catalog-only change in Postgres 11+, returns instantly.
ALTER TABLE orders
  ADD COLUMN currency text;

-- Optional: keep the lock attempt bounded so a long-running

SQL migration safety: add column nullable, backfill, then constrain

postgres migrations reliability
by codesnips 3 tabs
python
from django.db import models
from django.utils import timezone


class SoftDeleteQuerySet(models.QuerySet):
    def delete(self):

Soft-Delete in Django with a Custom Manager and QuerySet

django orm soft-delete
by codesnips 3 tabs