course
SQL Interview Practice Path
A challenge-oriented path with timed practice, debriefs, transfer checks, and mixed easy-to-hard SQL prompts.
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Who this path is for
A challenge-oriented path with timed practice, debriefs, transfer checks, and mixed easy-to-hard SQL prompts.
Audience: Interview candidates and experienced learners who want mixed prompts, debriefs, and pressure-tested transfer.
Prerequisites: Comfort with joins, grouping, null behavior, and reading problem statements carefully.
Observable learner outcomes
The course states outcomes as observable SQL behaviors that can be checked through local attempts, hidden variants, reviews, and projects.
- Classify interview-style SQL tasks by grain, join shape, and edge-case risk before coding.
- Practice easy-to-hard prompts with optional timing, debriefs, and transfer checks.
- Explain mistakes and improve under review without treating speed as the only quality signal.
Estimated effort range
Estimated effort range: 12-20 hours. This is a planning range, not a fake guarantee; prior SQL experience, review spacing, and project depth change the total.
Cumulative reviews and project requirements are part of completion, so finishing the path means more than viewing lessons.
Ordered syllabus
The syllabus below is rendered server-side so the course remains useful before the app loads.
| Module | Topic | Activities |
|---|---|---|
| M16 | Keys, Relationships, Cardinality, and Join Planning | 7 |
| M17 | INNER JOIN and Qualified Columns | 7 |
| M18 | LEFT JOIN, Missing Relationships, and Zero Counts | 7 |
| M19 | Multi-Table Joins and Fact Grain | 7 |
| M20 | Fan-Out, Pre-Aggregation, Self Joins, and Non-Equi Joins | 7 |
| M21 | Scalar and Set Subqueries | 7 |
| M22 | EXISTS, NOT EXISTS, and Correlation | 7 |
| M23 | Common Table Expressions and Query Pipelines | 7 |
| M24 | Set Operations and Compatible Result Shapes | 7 |
| M25 | Dates, Timestamps, Time Zones, and Half-Open Ranges | 7 |
| M26 | Period Grouping, Complete Calendars, Cohorts, and Retention Foundations | 7 |
| M27 | Window Foundations and Ranking | 7 |
| M28 | LAG, LEAD, and Period Change | 7 |
| M29 | Running Totals, Frames, Rolling Metrics, and Percent of Total | 7 |
| M30 | Logical Processing Order, Systematic Debugging, and Data Quality | 7 |
| M31 | INSERT, UPDATE, DELETE, and RETURNING | 7 |
| M32 | Transactions, Constraints, and Upserts | 7 |
| M33 | EXPLAIN, Index Fundamentals, and Query Quality | 7 |
Reviews, projects, and mastery
Completion uses independent attempts, delayed review, transfer evidence, and project milestones rather than simple page views.
Cumulative reviews, project requirements, and final transfer checks are visible parts of the course contract.
The prominent Start course action opens `/app`; path-specific practice links below are secondary routes for returning learners.