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Consolidate Disparate Data Sources in SQL

MediumSQL & Data Manipulation00:00
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Your question is Consolidate Disparate Data Sources in SQL. Take a moment with it on the right.

Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).

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Problem

Context

You are given multiple source extracts that do not share the same structure, naming, or completeness. In a financial reporting workflow, you need to consolidate them into one reliable dataset before analysis.

Core question

Walk through how you would use SQL to consolidate data from multiple disparate sources. In your answer, explain how you would standardize fields, align keys, handle missing values, resolve duplicates, and validate that the merged output is accurate.

Scope guidance

Keep your answer practical and specific to SQL-based consolidation. Focus on the sequence you would follow, the join and null-handling choices you would make, and how you would check for mismatches or data quality issues after combining the sources.