Merge pull request #614 from elementary-data/ele-2037-add-deprecated-…

…columns-to-alerts_dbt_source_freshness-due-to

ELE-2037: Add old columns to `alert_dbt_source_freshness` for backward compatability

models/edr/alerts/alerts_dbt_source_freshness.sql

@@ -33,7 +33,14 @@ select
   sources.meta,
   sources.owner,
   sources.package_name,
-  sources.path
+  sources.path,
+  -- These columns below are deprecated. We add them since this view
+  -- was used to be loaded into an incremental model with those columns, their names were later changed
+  -- and Databricks doesn't respect `on_schema_change = 'append_new_columns'` properly, as described here -
+  -- https://docs.databricks.com/en/delta/update-schema.html#automatic-schema-evolution-for-delta-lake-merge
+  results.error_after as freshness_error_after,
+  results.warn_after as freshness_warn_after,
+  results.filter as freshness_filter
 from results
 join sources on results.unique_id = sources.unique_id
 where {{ not elementary.get_config_var('disable_source_freshness_alerts') }} and lower(status) != 'pass'