In a data migration plan, which step should occur first?

• A. Migrate to production
• B. Discover source/target schemas
• C. Design ETL processes
• D. Validate with reconciliations

Answer: (B)

Understanding data structures and how data will move between systems is the first thing to establish in a data migration plan. Discovering source and target schemas reveals what data exists, how it’s organized, the fields and their data types, relationships, and the rules that govern those fields. This foundational knowledge shows you exactly how data should map from the source to the target, which is essential for any subsequent work.

With the schemas known, you can design the ETL processes to perform the correct transformations and mappings, anticipate data quality issues, and define how reconciliations will be performed. It also ensures that when you eventually move into production, the migration is guided by concrete structure and constraints rather than guesswork.

If you jump straight to moving data to production, or trying to design ETL without knowing the schemas, you’d risk incorrect mappings, data type mismatches, and failed loads. Validation and reconciliation make sense only after data has been transformed and loaded in a way that reflects the actual schemas, so they occur later in the plan.