Data Monitoring / Power BI Refresh & Data Reliability
Power BI: Schema drift in Power Query
A source deployment removes a column that a transformation references. Find the first failing applied step and compare its expected columns with the new source schema.
Environment and inputs: Power BI Desktop and Power BI service; gateway, connector, capacity and license capabilities depend on the deployed configuration.
Failure scenario
A source deployment removes a column that a transformation references. Confirm the cause before choosing a fix.
Evidence to collect
Find the first failing applied step and compare its expected columns with the new source schema. Record the time, affected scope and a healthy comparison interval.
Fix the confirmed cause
Agree a source contract or adapt the dependent transformation and verify downstream measures. Write the expected result first. Change one relevant setting at a time.
Check the result and hand over
Repeat the check for schema drift in power query using the same scope and a representative interval. Check that the symptom is resolved, expected records are present and downstream results are correct. If coverage, correctness or latency worsens, restore the recorded configuration through the agreed rollback process.
Scope and precautions
Prefer read-only access and limit queries to the relevant period or dataset. This example has not been tested on your systems. Test changes in an approved environment. Keep credentials and sensitive data out of shared evidence.