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Collections Funnel SQL Analysis
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Collections Funnel SQL Analysis

MediumSQL · PostgreSQL

Problem

Write a SQL query to analyze a collections funnel by stage, calculating conversion rates and drop-off between steps.

Use all available funnel stages and stage events. Count each account once per stage, including stages with no matching events.

Output

  1. One row per funnel stage with stage_name, entrants, previous_entrants, conversion_rate_pct, and dropoff_count
  2. Include the first stage with null prior-stage metrics
  3. Order by the defined stage sequence

Schema

funnel_stages
ColumnTypeDescription
stage_idPKINTUnique funnel stage identifier
stage_nameVARCHAR(100)Name of the collections funnel stage
stage_orderINTSequential position of the stage
collection_stage_events
ColumnTypeDescription
event_idPKINTUnique stage event identifier
account_idVARCHAR(30)Account associated with the event
stage_idINTFunnel stage reached by the account
entered_atDATEDate the account entered the stage
Tablesfunnel_stagescollection_stage_events
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