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Conversion Rate by Channel Segment

Medium
SQL & Data ManipulationJoinsGroup ByCase WhenAsked 6 times

Problem

BrightCart wants to measure how efficiently each acquisition channel converts users across customer segments. Write a PostgreSQL query to calculate conversion rate by channel and segment for users who signed up in January 2024.

A user is considered converted if they have at least one row in conversions with is_conversion = true within 30 days of their signup date.

Requirements

  1. Return one row per channel and segment.
  2. Count total signed-up users and converted users.
  3. Compute conversion rate as converted_users / total_users, rounded to 4 decimal places.
  4. Exclude users whose segment is NULL.
  5. Order results by conversion rate descending, then by channel and segment ascending.

Table Definitions

users

columntypedescription
user_idINTUnique user identifier
signup_dateDATEDate the user signed up
channelVARCHAR(50)Acquisition channel
segmentVARCHAR(50)Customer segment

conversions

columntypedescription
conversion_idINTUnique conversion event identifier
user_idINTUser tied to the conversion event
conversion_dateDATEDate of conversion event
is_conversionBOOLEANWhether the event counts as a conversion

channels

columntypedescription
channelVARCHAR(50)Channel name
channel_groupVARCHAR(50)Higher-level channel grouping

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
signup_dateDATEDate the user signed up
channelVARCHAR(50)Acquisition channel for the signup
segmentVARCHAR(50)Customer segment
conversions
ColumnTypeDescription
conversion_idPKINTUnique conversion event identifier
user_idINTUser associated with the event
conversion_dateDATEDate the conversion event occurred
is_conversionBOOLEANWhether the event should count as a conversion
channels
ColumnTypeDescription
channelPKVARCHAR(50)Channel name
channel_groupVARCHAR(50)Higher-level grouping of the channel

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