Performance & Indexing

1. 🚧 Sargability Deep Dive — Seek vs scan, avoid functions on indexed columns.
2. 🚧 Index Basics — Clustered vs nonclustered, included columns.
3. 🚧 Covering & Filtered Indexes — Cover hot queries; filter for selective subsets.
4. 🚧 Statistics & Sniffing — Cardinality, auto-stats, parameter sniffing overview.
5. 🚧 Execution Plans 101 — Operators, estimates vs actual, common shapes.
6. 🚧 Temp Tables vs Table Variables — When to use #temp vs @table; indexing and stats.