Data migration and validation from Excel
Problem
Excel files can mix formats, empty values, duplicates, and conventions that do not match the destination system’s rules.
Analysis
Before importing, I identify required columns, expected formats, identifiers, and rules for incomplete or inconsistent rows. The file is a source that needs review, not an already validated database.
Solution
I prepare a cleaning and validation stage before loading, with a clear report of records that need review. Accepted data is then ready to enter the system.
Validation
I check that records follow the rules and that the load does not introduce duplicates or incompatible values. Rejected rows remain separate for later correction.
Result or learning
Learning: separating validation from import reduces errors and lets the source be corrected without unnecessarily changing the destination system.