Course Index
SQL Mastery
A structured, interview-grade path through SQL — from join mechanics and execution order to windowing, sessionization, and the patterns FAANG interviewers actually test for.
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modules complete
01
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JOINS
Everything from "what is a join" to how a query planner physically executes one, and how FAANG interviewers trap people who only memorized syntax.
Complete
24 sections
02
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Subqueries
A query inside a query. The tool for "compare against something you have to compute first" — and the tool interviewers use to test whether you understand execution order, not just syntax.
Complete
17 sections
03
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CTEs (Common Table Expressions)
From "what is WITH" to building multi-stage ETL pipelines out of chained CTEs, and knowing exactly when the optimizer will and won't materialize one for you.
Complete
18 sections
06
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Window Functions
From "what does OVER() even mean" to running totals, gap-and-island detection, sessionization, and retention analysis — the single most tested topic in FAANG SQL interviews.
Complete
18 sections