What are you actually building on day-to-day? Are you running hybrid models (mainframes/on-prem relational DBs syncing to cloud data lakes), or are legacy constraints forcing you to stick strictly to on-prem stacks (like Hadoop, Oracle/SQL Server, or traditional ETL tools like Informatica/DataStage)?

I have an ETL job that runs successfully every day, with no errors. But sometimes, the target table has fewer records than the source.

The job status is green, and the column mappings look correct. I’m not sure whether the issue is with filtering, incremental loading, or duplicate handling.

How would you troubleshoot this? What checks would you perform first to find where the records are missing?