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Learn to read SQL Server execution plans using row estimates, operators, warnings, I/O, CPU, waits, and a repeatable query-tuning workflow.

Practical SQL Server DMV queries for CPU, memory, blocking, waits, I/O, slow queries, and indexes, with baseline and safety guidance.

Learn how SQL Server chooses Nested Loops, Hash Join, and Merge Join. This guide explains execution plans, Outer/Inner roles, Sort behavior, and practical examples.

Learn how to compare table data between SQL Server instances using EXCEPT and tablediff.exe. Includes sample data, linked server setup, output examples, and how tablediff uses checksums.

Understand SQL Server storage internals: page structure, extents, allocation units, GAM/SGAM/PFS/IAM allocation pages, plus transaction log basics (VLF, log blocks, LSN).

Learn the difference between unallocated space and unused space in SQL Server. Understand pages, extents, and how sp_spaceused reports storage.

Learn how to map a high-CPU OS thread ID to a specific SQL Server session and query. This step-by-step guide uses DMVs and Process Explorer to connect OS-level threads with SQL Server workloads for easier performance troubleshooting.

Learn how SQL Server transaction isolation levels work, from Read Uncommitted to Snapshot and RCSI. Understand dirty reads, non-repeatable reads, and phantom reads.

Deep dive into optimized locking in SQL Server 2025 and Azure SQL: TID, LAQ, SIL, setup steps, and before/after demos to reduce blocking and deadlocks.

Learn what Quorum is in Windows Server Failover Cluster (WSFC). Understand how votes, witnesses, and Dynamic Quorum work, and explore configuration methods, scenarios, and best practices.