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SQL, APIs, and OOP
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SQL, APIs, and OOP

MediumSQL · PostgreSQL

Problem

Explain how you use SQL queries and APIs together, and how OOP concepts show up in your personal projects.

For a representative implementation, write a query over the supplied API request and SQL execution records, then explain how an application could expose or consume this data through an API.

Output

  1. One row per non-null endpoint with at least two requests during January 2026
  2. Columns: endpoint, request_count, successful_request_count, avg_sql_duration_ms, and sql_execution_count
  3. Order by successful requests descending, then endpoint ascending

Schema

api_requests
ColumnTypeDescription
request_idPKINTUnique API request identifier
endpointVARCHAR(100)Requested API endpoint
response_statusINTHTTP response status code
requested_atTIMESTAMPTime when the API request was received
sql_executions
ColumnTypeDescription
execution_idPKINTUnique SQL execution identifier
request_idINTAPI request associated with the SQL execution
duration_msDECIMAL(10,2)SQL execution duration in milliseconds
Tablesapi_requestssql_executions
Interviewer

Your question is SQL, APIs, and OOP. Start with the requirements and the two tables in the Question tab.

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