How do you return the Nth related record from joined tables in PostgreSQL? Did you know that it has a few more options than other databases? Use DISTINCT ON and window functions that solve common temporal join challenges and avoid N+1 query problems.

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Temporal joins retrieve the Nth related record from joined tables, a common but complex SQL pattern. PostgreSQL offers elegant solutions using DISTINCT ON for first/last records and window functions with CTEs for more complex cases. These approaches avoid duplicate row bugs from naive implementations and eliminate N+1 query performance issues common in ORM-based solutions. The key is proper ordering with tie-breaker logic using primary keys to handle duplicate timestamps.

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