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SQL Variant Comparison With Ranking
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SQL Variant Comparison With Ranking

MediumSQL · PostgreSQL

Problem

Write a SQL query to compare experiment variants using grouped metrics and a window function for ranking.

Use the experiment_variants, experiment_assignments, and experiment_events tables. Calculate exposed users and distinct converting users for experiment 100, treating variants without assignments as having zero exposed users.

Output

  1. One row per variant in experiment 100.
  2. Columns: variant_name, exposed_users, conversions, conversion_rate, and conversion_rank.
  3. Rank by conversion rate descending, with ties sharing a rank. Order by rank ascending, then variant ID.

Schema

experiment_variants
ColumnTypeDescription
variant_idPKINTUnique variant identifier
experiment_idINTExperiment identifier
variant_nameVARCHAR(100)Variant label
experiment_assignments
ColumnTypeDescription
assignment_idPKINTUnique assignment identifier
experiment_idINTExperiment identifier
variant_idINTAssigned variant identifier
user_idINTUser exposed to the experiment
experiment_events
ColumnTypeDescription
event_idPKINTUnique event identifier
experiment_idINTExperiment identifier
user_idINTUser generating the event
event_nameVARCHAR(50)Recorded event type
Tablesexperiment_variantsexperiment_assignmentsexperiment_events
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