SQL Server Query Execution: Expectation vs Reality

on YouTube ↗49m

" summary

Covers surprising differences between expected and actual SQL Server query execution behavior (like slower execution after changing options, queries never starting or hanging, and index seeks turning into full scans). Explains internals of SQL Server — query planning, execution choices and related settings — to show why those unexpected outcomes occur and how execution decisions are made.

AI-written summary · about

" chapters (11)

1. 0:00Introduction
2. 1:13Parameter sniffing
3. 8:54Worst sniffing case
4. 16:23SSMS vs app timing
5. 16:43Cardinality Estimation
6. 25:51CE impact
7. 26:11Deadlocks in SQL Server
8. 31:43Deadlocks and bugs
9. 39:24Optimizer internals
10. 45:56Optimizer timeout
11. 46:17Summary

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