Supabase Backend Platform Skill

progressive_disclosure: entry_point: summary: "Open-source Firebase alternative with Postgres, authentication, storage, and realtime" when_to_use: - "When building full-stack applications" - "When auth, database, and storage are required" - "When realtime subscriptions are needed" - "When using Next.js, React, or Vue" quick_start: - "Create project on Supabase console" - "npm install @supabase/supabase-js" - "Initialize client with URL and anon key" - "Use auth, database, storage, realtime" token_estimate: entry: 80-95 full: 5000-6000

Supabase Fundamentals

What is Supabase?

Open-source Firebase alternative built on:

• Postgres Database: Full SQL database with PostgREST API
• Authentication: Built-in auth with multiple providers
• Storage: File storage with image transformations
• Realtime: WebSocket subscriptions to database changes
• Edge Functions: Serverless functions on Deno runtime
• Row Level Security: Postgres RLS for data access control

Project Setup

# Install Supabase client
npm install @supabase/supabase-js

# Install CLI for local development
npm install -D supabase

# TypeScript types
npm install -D @supabase/supabase-js

Client Initialization

// lib/supabase.ts
import { createClient } from '@supabase/supabase-js'

const supabaseUrl = process.env.NEXT_PUBLIC_SUPABASE_URL!
const supabaseAnonKey = process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY!

export const supabase = createClient(supabaseUrl, supabaseAnonKey)

// With TypeScript types
import { Database } from '@/types/supabase'

export const supabase = createClient<Database>(
  supabaseUrl,
  supabaseAnonKey
)

Database Operations

PostgREST API Basics

Supabase auto-generates REST API from Postgres schema:

// SELECT * FROM posts
const { data, error } = await supabase
  .from('posts')
  .select('*')

// SELECT with filters
const { data } = await supabase
  .from('posts')
  .select('*')
  .eq('status', 'published')
  .order('created_at', { ascending: false })
  .limit(10)

// SELECT with joins
const { data } = await supabase
  .from('posts')
  .select(`
    *,
    author:profiles(name, avatar),
    comments(count)
  `)

// INSERT
const { data, error } = await supabase
  .from('posts')
  .insert({ title: 'Hello', content: 'World' })
  .select()
  .single()

// UPDATE
const { data } = await supabase
  .from('posts')
  .update({ status: 'published' })
  .eq('id', postId)
  .select()

// DELETE
const { error } = await supabase
  .from('posts')
  .delete()
  .eq('id', postId)

// UPSERT
const { data } = await supabase
  .from('posts')
  .upsert({ id: 1, title: 'Updated' })
  .select()

Advanced Queries

// Full-text search
const { data } = await supabase
  .from('posts')
  .select('*')
  .textSearch('title', 'postgresql', {
    type: 'websearch',
    config: 'english'
  })

// Range queries
const { data } = await supabase
  .from('posts')
  .select('*')
  .gte('created_at', '2024-01-01')
  .lte('created_at', '2024-12-31')

// Array contains
const { data } = await supabase
  .from('posts')
  .select('*')
  .contains('tags', ['postgres', 'supabase'])

// JSON operations
const { data } = await supabase
  .from('users')
  .select('*')
  .eq('metadata->theme', 'dark')

// Count without data
const { count } = await supabase
  .from('posts')
  .select('*', { count: 'exact', head: true })

// Pagination
const pageSize = 10
const page = 2
const { data } = await supabase
  .from('posts')
  .select('*')
  .range(page * pageSize, (page + 1) * pageSize - 1)

Database Functions and RPC

// Call Postgres function
const { data, error } = await supabase
  .rpc('get_trending_posts', {
    days: 7,
    min_score: 10