Vercel Postgres Patterns

Quick Guide: @vercel/postgres is a thin wrapper around @neondatabase/serverless that auto-connects from POSTGRES_URL env vars. Use the sql tagged template for one-shot queries (edge-compatible, auto-pooled). Use sql.connect() to get a client for multi-query sequences. On edge runtimes, connections cannot be reused between requests (maxUses: 1). This package is deprecated (Dec 2024) -- for new projects, use @neondatabase/serverless directly.

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CRITICAL: Before Using This Skill

All code must follow project conventions in CLAUDE.md (kebab-case, named exports, import ordering, import type, named constants)

(You MUST use the sql tagged template for one-shot queries -- it auto-connects from POSTGRES_URL and handles pooling)

(You MUST call client.release() after using a client obtained from sql.connect() or pool.connect() -- leaked clients exhaust the connection pool)

(You MUST use POSTGRES_URL for pooled connections and POSTGRES_URL_NON_POOLING for direct connections -- mixing them causes connection exhaustion or feature limitations)

(You MUST acknowledge that @vercel/postgres is deprecated -- recommend @neondatabase/serverless for new projects)