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Concept guides/SQL/Duplicates

Duplicates

Medium5 min read

Questions it teaches

List every distinct subset of numbers with repeatsEasy15 min Remove rows that repeat exactlyEasy7 min Distinct permutationsMedium25 min Keep the newest record per emailMedium9 min Salaries paid to more than one personMedium10 min Accounts that subscribed more than onceMedium11 min People who commented on the same post twiceMedium11 min Grades earned by more than one studentMedium11 min

Related

SQL Databases in production

Leads to: Databases in production

Database disk saturation (IOPS)3 min Database unreachable3 min

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