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Consecutive Activity Days Query
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Consecutive Activity Days Query

MediumSQL · PostgreSQL

Problem

Given a table of user interactions, write a query to find consecutive days of website activity using SQL window functions.

Return activity streaks containing at least two consecutive calendar days. Multiple interactions by the same user on one date should count as one active day, and rows with a missing interaction date should be excluded.

Output

  1. One row per user streak with user_id, start_date, end_date, and consecutive_days.
  2. Include streaks with at least two days.
  3. Order by user_id, then start_date ascending.

Schema

user_interactions
ColumnTypeDescription
interaction_idPKINTUnique identifier for the interaction
user_idINTIdentifier of the website user
interaction_dateDATECalendar date on which the interaction occurred
interaction_typeVARCHAR(30)Type of website interaction
Tablesuser_interactions
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