The ETL does the one to one mapping of what is there between BigDataInsightUCSource and what is there in BigDataInsightUC. so the main thing to watch out for is data missing in BigDataInsightUCSource.
There may be cases where the ETL may fail and that could render incomplete data. But because the BigDataInsightUCSource has a day wrap interval and the ETL rus every 15 minutes which means if the ETL is not successful due to some SQL Server issues, it has the whole day to recover the data if needed.
