Level up your SQL skills as a developer
summary
Explains how the SQL query optimizer evaluates alternative plans by estimating costs and choosing the lowest-cost plan, and when that model surprises developers. Shows concrete actions: avoid SELECT statements, create indexes on queried columns and pick index types that match joins and filters, use computed or composite columns sparingly and materialize when needed*. Demonstrates how small schema changes and targeted WHERE clauses change the planner’s choice and measurably improve query latency.
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chapters (7)
- 0:00Introduction to SQL optimization
- 1:38Why query optimization matters
- 7:17Query optimizer basics
- 10:17Selecting only needed columns
- 12:25When to use joins vs subqueries
- 15:45Avoiding unnecessary calculations
- 18:45Summary and Q&A
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