Postgres's lateral joins allow for quite the good eDSL Did you know that a single `LATERAL` clause can replace an entire stored‑procedure language in many reporting scenarios? In PostgreSQL, the combination of **LATERAL** with set‑returning functions turns ordinary `SELECT` statements into a powerful, **embedded domain‑specific language (eDSL)** for complex data shaping—without leaving the comfort of plain **SQL**. In This Article What is a LATERAL Join and Why It Feels Like an eDSL Building Complex Transformations with LATERAL (Code Walkthrough) Real‑World Use Cases – When LATERAL Beats MySQL & Traditional Approaches Why This Matters – Business Impact & Maintainability Actionable Takeaways & Best‑Practice Checklist Frequently Asked Questions What is a LATERAL Join and Why It Feels Like an eDSL The syntax is simple: `FROM …, LATERAL (sub‑query) AS alias`. It sounds harmless, but what it does is feed each row from the preceding `FROM` item straight into t...
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