Detective's Journal

SQL COALESCE Explained: Handle NULL Values Like a Pro

Learn how SQL COALESCE works with practical examples. Handle NULL values, set defaults, and master COALESCE vs ISNULL vs IFNULL across all databases.

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SQL Views Explained: What They Are, How They Work, and When to Use Them

March 5, 2026

11 min read

Hristo Bogoev

SQL Views Explained: What They Are, How They Work, and When to Use Them

Learn what SQL views are, how they work internally, and when to use them. Includes visual diagrams, practical examples, views vs tables comparison, and common mistakes.

View vs Materialized View: What's the Difference? (With Examples)

Learn the key differences between views and materialized views in SQL. Visual comparison, code examples, decision guide, and when to use each.

SQL CASE WHEN: The Complete Guide With Examples (2026)

Learn SQL CASE WHEN with practical examples. Master simple CASE, searched CASE, CASE with aggregates, and common patterns every SQL developer needs.

What Is a CTE in SQL? A Visual Guide with Examples (2026)

Learn what CTEs (Common Table Expressions) are in SQL, when to use them, and master the WITH clause with visual examples. Includes recursive CTEs.

Clustered vs Nonclustered Index: When to Use Each (With Visual Examples)

Learn the key differences between clustered and nonclustered indexes in SQL. Visual diagrams, performance comparisons, and practical examples for better database design.

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