Why Does AWS Glue Show System Columns as TIMESTAMP Instead of TIMESTAMPTZ?

Question

Fivetran system columns, such as _fivetran_deleted, are created in AWS Glue as the TIMESTAMP type, but the values include a time zone. For example, 2019-03-08 15:00:56.141000 UTC. Why aren’t these columns created as TIMESTAMPTZ?

Environment

Destination: S3 Data Lake

Answer

AWS Glue supports the TIMESTAMP column type, but not TIMESTAMPTZ. When we create system columns like _fivetran_deleted, we define them as TIMESTAMPTZ in the Iceberg table metadata. This preserves the time zone information, even though AWS Glue displays the column as TIMESTAMP.