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Concept guides/SQL/Conditional aggregation

Conditional aggregation

Hard5 min read

Questions it teaches

Live and churned MRR per tierMedium11 min Sort by a status priority, not alphabeticallyMedium12 min Paid and refunded side by sideHard13 min Did each user ever purchaseHard13 min Money in and money out, per accountHard14 min

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SQL Databases in production

Leads to: Databases in production

Database disk saturation (IOPS)3 min Database unreachable3 min

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