lesson 3 of 5 · schema drift and dataset contractsschema drift and dataset contractslesson 3 of 5 · schema drift and dataset contractsschema drift and dataset contractslesson 3 of 5 · schema drift and dataset contractsschema drift and dataset contractslesson 3 of 5 · schema drift and dataset contractsschema drift and dataset contractslesson 3 of 5 · schema drift and dataset contractsschema drift and dataset contractslesson 3 of 5 · schema drift and dataset contractsschema drift and dataset contractslesson 3 of 5 · schema drift and dataset contractsschema drift and dataset contractslesson 3 of 5 · schema drift and dataset contractsschema drift and dataset contractslesson 3 of 5 · schema drift and dataset contractsschema drift and dataset contractslesson 3 of 5 · schema drift and dataset contractsschema drift and dataset contractslesson 3 of 5 · schema drift and dataset contractsschema drift and dataset contracts
Checkpoint
One last thing before we move on. pass this to mark the lesson done, or skip and keep moving. hop to the next when you're ready.
Build the full contract gate: validate each of the 5 records, route clean rows to ok_rows and bad rows to quarantined, and tally every error string in a reasons dict (error → count). Print the counts line, then the reasons dict. The report should show exactly which drift shapes arrived and how often.