postgresql

Use schema-per-tenant isolation where the tenant is resolved per authenticated request and never hardcoded in business logic. Every migration and query must work across schemas, and any design that weakens this isolation should be rejected.

Check that migrations are versioned, reviewable, and reversible where applicable, with rollback or backfill plans for destructive changes. Never rely on TypeORM synchronize as the schema evolution policy in any environment.

Use numeric(p,s) for money and exact values, and timestamptz for time. Avoid float for billable amounts, timestamp without time zone, and the money type, since they introduce rounding or timezone bugs.

Use jsonb only for optional or variable-shape attributes that do not yet justify their own table. If you query internal jsonb fields, add a suitable index or extract the value into a materialized or generated column.

Modules should not query each other's tables directly even when sharing a database. Define a contract, projection, or controlled integration for cross-module data to preserve bounded context boundaries.

Physical deletes destroy evidence needed for audit, compliance, and traceability. Prefer a business status or logical deletion, and evaluate retention and operational impact before removing any records.