Go ab initio , or go home.
Ab initio data quality is painful because it forces you to say
Don't wait until data hits the Warehouse to check its quality. Implement validation logic at the . By catching errors at the source, you prevent "garbage in, garbage out" scenarios and save on processing costs. Automated Reconciliation
Replace NULL with explicit semantics. Use -999 for "offline," -9999 for "out of range," or better—split the column into value and value_metadata_flag .
We have it backwards.
An ab initio system ensures that:
Does the "Status" code in the Source system match the "Status" code in the Warehouse?