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Window Functions for Top Issues
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Window Functions for Top Issues

MediumSQL · PostgreSQL

Problem

Write a SQL query using window functions to identify the top three repeating service issues by home appliance category for Cinch Home Services.

Use completed service requests only. Exclude requests without a valid appliance category or issue, and break equal-count ties alphabetically by issue name.

Output

  1. One row per qualifying issue and appliance category.
  2. Columns: category_name, issue_name, repeat_count, and issue_rank.
  3. Include only the top three issues within each category, ordered by category name, rank, and issue name.

Schema

service_requests
ColumnTypeDescription
request_idPKINTUnique service request identifier
category_idINTAppliance category identifier
issue_idINTReported service issue identifier
statusVARCHAR(20)Current service request status
appliance_categories
ColumnTypeDescription
category_idPKINTUnique appliance category identifier
category_nameVARCHAR(50)Home appliance category name
service_issues
ColumnTypeDescription
issue_idPKINTUnique service issue identifier
issue_nameVARCHAR(80)Standardized service issue name
Tablesservice_requestsappliance_categoriesservice_issues
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Your question is Window Functions for Top Issues. Start with the requirements and the three tables in the Question tab.

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