Wasn't expecting something this technical in a BA screen.
Start by clarifying the data sources and the nature of the ID mismatches, then describe a systematic process for profiling, matching, and validating joins. Emphasize trade-offs between accuracy, performance, and complexity, and highlight the importance of root cause analysis to prevent future mismatches.
Pro tip: Mention that you would first check if the mismatches are due to data quality issues or schema differences, and propose a short-term fix (e.g., fuzzy matching) while advocating for a long-term solution like a canonical ID system.
Profile the data sources to identify the types and causes of ID mismatches (e.g., formatting, missing values, different granularity).
Select an appropriate technique such as exact matching, fuzzy matching, or probabilistic record linkage based on the mismatch patterns and business requirements.
Implement the join logic, possibly using a multi-step process, and validate the results with metrics like match rate and false positive rate.
Address edge cases (e.g., many-to-many relationships) and ensure the solution scales with data volume, considering performance optimizations.
Analyze root causes of mismatches and propose long-term fixes such as standardizing ID formats or creating a master data management system.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.