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SQL Joins and Aggregations

MediumSQL · PostgreSQL00:00
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Your question is SQL Joins and Aggregations. Start with the requirements and the two tables on the right.

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Problem

Verisk Analytics uses ISO ClaimSearch data to support insurer portfolio analysis. Write a PostgreSQL query that joins policy records to claim events and summarizes 2025 claims by policy segment.

Requirements

  1. Use a LEFT JOIN from policies to claim_events, retaining policy segments with no qualifying 2025 claims.
  2. Group results by state_code and policy_type.
  3. Return distinct policy count, 2025 claim count, and total incurred amount. Treat missing incurred amounts and segments without claims as zero.
  4. Sort by state, with NULL states last, then by policy type.

Schema

policies
ColumnTypeDescription
policy_idPKINTUnique policy identifier
state_codeVARCHAR(2)Two-letter policy state
policy_typeVARCHAR(30)Insurance line of business
claim_events
ColumnTypeDescription
claim_idPKINTUnique claim identifier
policy_idINTPolicy associated with the claim
reported_dateDATEDate the claim was reported
incurred_amountDECIMAL(12,2)Current incurred loss amount
statusVARCHAR(20)Claim processing status
Tablespoliciesclaim_events
Your solutionPostgreSQL
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