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SQL Optimization for Healthcare Data
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SQL Optimization for Healthcare Data

MediumSQL · PostgreSQL

Problem

Explain your approach to SQL optimization for large, complex healthcare datasets at Candid Health.

Demonstrate the approach by writing a query against the provided claims, provider, and payer data. Include only finalized claims submitted during Q1 2025.

Output

  1. One row per payer and submission month, with service_month, payer_name, finalized_claims, denied_claims, denial_rate_pct, avg_processing_hours, and prior_month_denial_rate_pct.
  2. Exclude claims without a finalized adjudication or without matching provider and payer records.
  3. Sort by month ascending, then payer name ascending.

Schema

claims
ColumnTypeDescription
claim_idPKINTUnique claim identifier
provider_idINTBilling provider identifier
payer_idINTInsurance payer identifier
submitted_atTIMESTAMPClaim submission timestamp
adjudicated_atTIMESTAMPClaim adjudication timestamp
statusVARCHAR(20)Claim processing status
allowed_amountNUMERIC(12,2)Allowed claim amount
providers
ColumnTypeDescription
provider_idPKINTUnique provider identifier
provider_nameVARCHAR(100)Provider display name
specialtyVARCHAR(80)Provider specialty
payers
ColumnTypeDescription
payer_idPKINTUnique payer identifier
payer_nameVARCHAR(100)Payer display name
payer_typeVARCHAR(40)Payer classification
Tablesclaimsproviderspayers
Interviewer

Your question is SQL Optimization for Healthcare Data. Start with the requirements and the three tables in the Question tab.

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