Metadata Fields

Beyond the columns defined in each stream's schema, Propexo Connect automatically appends a set of system metadata columns to every record written to a destination. These fields help you trace data lineage, debug sync issues, and understand how records were processed.

System-Appended Columns

Field	Description	Data Type
_propexo_id	A row hash used for deduplication	String
_propexo_loaded_at	Timestamp recording when Propexo Connect sent the record to the destination	Timestamp (UTC)
_propexo_extracted_at	Timestamp recording when Propexo Connect retrieved the record from the source system	Timestamp (UTC)
_propexo_sync_id	A UUID identifier assigned per sync execution	String