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Segments by Tasks Per Login
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Segments by Tasks Per Login

MediumSQL · PostgreSQL

Problem

Given a table of user logins and a table of task executions, write a query to find which user segments have the highest ratio of tasks executed per login.

Count every task execution, exclude logins without a non-null segment, and return all segments tied for the highest ratio.

Output

  1. One row per highest-performing segment
  2. Columns: user_segment, login_count, task_count, and tasks_per_login
  3. Sort by user_segment ascending to break ties consistently

Schema

user_logins
ColumnTypeDescription
login_idPKINTUnique identifier for a login event
user_idINTIdentifier of the user who logged in
user_segmentVARCHAR(50)Segment assigned to the user at login time
login_atTIMESTAMPTimestamp of the login event
task_executions
ColumnTypeDescription
execution_idPKINTUnique identifier for a task execution
user_idINTIdentifier of the user whose task was executed
executed_atTIMESTAMPTimestamp of the task execution
statusVARCHAR(20)Execution status; every row represents an execution
Tablesuser_loginstask_executions
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