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SQL and Database Fundamentals
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SQL and Database Fundamentals

MediumSQL · PostgreSQL

Problem

Tell me about your experience with SQL and choosing the right database type for a data engineering solution.

Demonstrate your approach by analyzing the supplied workload data for active workloads during January 2026. Classify each workload using query mix, consistency requirements, processed rows, and latency.

Output

  1. One row per active workload
  2. Columns: workload_name, total_queries, read_percentage, average_latency_ms, average_rows_processed, recommended_database_type
  3. Include active workloads with no qualifying events, using zero or NULL metrics as appropriate
  4. Sort by workload_name ascending

Schema

workload_profiles
ColumnTypeDescription
workload_idPKINTUnique workload identifier
workload_nameVARCHAR(100)Name of the data workload
business_domainVARCHAR(60)Business area associated with the workload
is_activeBOOLEANWhether the workload is currently active
query_events
ColumnTypeDescription
event_idPKINTUnique query event identifier
workload_idINTWorkload associated with the query event
occurred_onDATEDate when the query occurred
query_typeVARCHAR(20)Query operation type, such as read or write
latency_msDECIMAL(10,1)Observed query latency in milliseconds
rows_processedINTNumber of rows processed by the query
consistency_requiredBOOLEANWhether the query requires strong consistency
Tablesworkload_profilesquery_events
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