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SQL Window Query for Geo Logins
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SQL Window Query for Geo Logins

HardSQL · PostgreSQL

Problem

Write a complex SQL query utilizing window functions and multi-table joins to identify users who logged in from two different geographical locations within a 10-minute window.

Use consecutive login records for each user. Include only transitions with two known, different locations and a time difference of no more than 10 minutes.

Output

  1. One row per qualifying login transition.
  2. Return user_id, user_name, previous_login_at, previous_location, current_login_at, current_location, and minutes_between.
  3. Order by user_id, then current_login_at, then current_login_id.

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
user_nameVARCHAR(100)User's display name
locations
ColumnTypeDescription
location_idPKINTUnique geographical location identifier
cityVARCHAR(100)City associated with the login location
countryVARCHAR(100)Country associated with the login location
login_events
ColumnTypeDescription
login_idPKINTUnique login event identifier
user_idINTUser who generated the login event
logged_atTIMESTAMPTimestamp when the login occurred
location_idINTLocation associated with the login, when available
Tablesuserslogin_eventslocations
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