UNIQUE NOT NULL columns should also work in order to perform backfills. This change relaxes the check on backfill requirements to use those columns if a primary key is not available.
Validation will still error out if no suitable column is found
Note: this also fixes the unique retrieval from schema, where we were failing to understand composed unique indices, resulting in columns flagged as unique where they weren't really unique.
UNIQUE NOT NULL columns should also work in order to perform backfills. This change relaxes the check on backfill requirements to use those columns if a primary key is not available.
Validation will still error out if no suitable column is found
Note: this also fixes the
uniqueretrieval from schema, where we were failing to understand composed unique indices, resulting in columns flagged as unique where they weren't really unique.