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Detect and Clean Duplicate Claims
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Detect and Clean Duplicate Claims

MediumSQL · PostgreSQL

Problem

Write a SQL query to identify duplicate records in a healthcare claims table and explain how you would clean them.

For this exercise, treat claims with the same business fields as duplicates and retain the earliest ingested record. Explain how you would review, archive, and remove later duplicates safely.

Output

  1. One row per duplicate claim that should be removed.
  2. Columns: duplicate_claim_id, claim_number, duplicate_group_count, and keep_claim_id.
  3. Sort by claim_number, then duplicate_claim_id ascending.

Schema

healthcare_claims
ColumnTypeDescription
claim_idPKINTUnique physical claim record identifier
claim_numberVARCHAR(20)Business claim number
member_idVARCHAR(20)Covered member identifier
provider_idVARCHAR(20)Billing provider identifier
service_dateDATEDate services were provided
procedure_codeVARCHAR(10)Healthcare procedure code
billed_amountDECIMAL(10,2)Amount billed for the claim line
ingestion_timestampTIMESTAMPTimestamp when the record entered the claims table
Tableshealthcare_claims
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