Pathwise

Manuals / SQL / Checkpoint 11

D · Performance · advanced · Gate · Week 8–10 · Checkpoint 11 of 12

Checkpoint B — SQL job-ready

Final gate: read path through write path, transactions, and index literacy — the bar for "I can query databases" in QA or dev interviews.

Path progress
86%

Step 1 of 3

Pass criteria

  • 20+ saved queries covering SELECT, JOIN, GROUP BY, CTE, mutation
  • 3-table JOIN query with correct grain documented in comment
  • GROUP BY + HAVING aggregation answering a real business question
  • SAFETY.md ritual followed on UPDATE practice (SELECT preview → txn → ROLLBACK)
  • Transfer transaction script with COMMIT and ROLLBACK demonstrated
  • EXPLAIN before/after index with written conclusion in notes
  • Can explain ACID and when to use a transaction in 2 minutes
Pass criteriaDrag stickies · tap for tips
Study mapDrag stickies · tap for tipsKeep it shortdrag · tap →Name the waitdrag · tap →Scope locatorsdrag · tap →Trace when stuckdrag · tap →One browser firstdrag · tap →Isolate statedrag · tap →Assert the UIdrag · tap →Retry wiselydrag · tap →Seed datadrag · tap →Close the loopdrag · tap →Keep it shortdrag · tap →Name the waitdrag · tap →Scope locatorsdrag · tap →Trace when stuckdrag · tap →One browser firstdrag · tap →Isolate statedrag · tap →Pathwise hackdrag · tap →Pass criteriadrag · tap →Try thisdrag · tap →Follow the dashed drag · tap →

Do this now

Verify every item. Fix gaps this week.

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Chapter learning outcomes
  • Interview SQL topics
  • Portfolio of saved queries

Clear these before you leave

Side quest

Query portfolio

Curate 5 best queries in sql-notes/portfolio/ with README explaining each.