PostgreSQL Patterns (node-postgres)

Quick Guide: Use the pg package (v8.x) for direct PostgreSQL access. Always use Pool -- never create individual Client instances in application code. Use parameterized queries ($1, $2) for ALL user input -- never interpolate strings into SQL. For transactions, check out a dedicated client with pool.connect() and use BEGIN/COMMIT/ROLLBACK in a try/catch/finally that always calls client.release(). Handle the pool error event to prevent process crashes from idle client errors. Use pg-query-stream for large result sets to avoid loading everything into memory.

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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 parameterized queries ($1, $2, ...) for ALL values -- NEVER concatenate or interpolate user input into SQL strings)

(You MUST use Pool for all database access -- NEVER create standalone Client instances in application code)

(You MUST release clients back to the pool in a finally block after pool.connect() -- leaked clients exhaust the pool and hang the application)

(You MUST handle the error event on Pool instances -- unhandled idle client errors crash the Node.js process)