This article presents ten advanced SQL concepts—including CTEs, recursive CTEs, temporary functions, CASE‑WHEN pivots, EXCEPT vs NOT IN, self‑joins, ranking window functions, delta calculations, cumulative sums, and date‑time manipulation—each explained with concrete examples and code snippets.
This article showcases a spectacular PostgreSQL query that implements the classic Tetris game using recursive CTEs, provides the full source code, highlights a known long‑run disk‑usage issue, and then presents several other impressive SQL snippets and a concise checklist for writing high‑quality SQL.
This article explains the meaning and optimization strategies for various MySQL EXPLAIN EXTRA hints—including Impossible WHERE/HAVING, No matching rows, Recursive queries, Rematerialize, and canned N databases—provides example execution plans, code snippets, and performance comparisons to help developers write more efficient SQL statements.
This article presents ten essential advanced SQL techniques—including CTEs, recursive CTEs, temporary functions, CASE‑WHEN pivots, EXCEPT vs NOT IN, self‑joins, ranking windows, delta calculations, cumulative totals, and date‑time manipulation—each explained with clear examples and code snippets for interview preparation.
This article explains how MySQL 8.0's WITH clause can be combined with INSERT, UPDATE, DELETE, recursive common table expressions, multiple CTEs and derived tables to generate data, create date sequences, and simplify everyday SQL programming with practical code examples.
This article explains how to extract the top N records for each group in PostgreSQL, compares the slow window‑function approach with a fast recursive‑CTE and set‑returning function solution, and shows performance results dropping from over 20 seconds to under half a second.
