Crucial Exams

CompTIA Data+ DA0-002 (V2) Practice Question

A data analyst stores each month's e-commerce transactions in separate tables (sales_2025_m01 and sales_2025_m02). The two tables have identical column names and data types. The analyst must write one query that appends the February rows directly beneath the January rows, preserves any duplicate transaction records for later quality checks and runs as fast as possible on tens of millions of rows. Which SQL set operator best satisfies these requirements?

  • INNER JOIN

  • UNION ALL

  • UNION

  • FULL OUTER JOIN

CompTIA Data+ DA0-002 (V2)
Data Acquisition and Preparation
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