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Detect Duplicate Accounts
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Detect Duplicate Accounts

MediumSQL · PostgreSQL

Problem

Write a SQL query to identify potential duplicate Robinhood accounts based on matching IP addresses and sign-up timestamps.

Use the robinhood_accounts table. Treat two different accounts as a potential duplicate pair only when both values are present and exactly match.

Output

  1. One row per potential duplicate account pair.
  2. Include account_id_1, account_id_2, ip_address, and signed_up_at.
  3. Order by ip_address, signed_up_at, account_id_1, and account_id_2 ascending.

Schema

robinhood_accounts
ColumnTypeDescription
account_idPKINTUnique Robinhood account identifier
ip_addressVARCHAR(45)IP address recorded during account sign-up
signed_up_atTIMESTAMPTimestamp when the account was created
Tablesrobinhood_accounts
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