If an external system writes Parquet data and corresponding duplicate records are enqueued, which statement is true regarding the retention of these records in the orders table?

The retention of records in the orders table when external systems write Parquet data with duplicate entries can vary based on the implementation and configuration of the data processing pipeline. The statement that all records, including duplicates created hours apart, may be retained is reflective of common behaviors observed in data lakes and systems that utilize Parquet for storage.

In many scenarios, when data is written to a table, especially one backed by a distributed storage system such as those commonly associated with big data technologies, the retention policy does not automatically deduplicate or filter out records during writing. As a result, each record that is written, including duplicates, will be stored in the table unless specific deduplication logic is implemented post-write or during the query execution phase.

This approach contrasts with deduplication approaches, which require additional processing steps to ensure that only unique entries are kept, and with options that suggest automatic deletion of duplicates during the writing process, which typically is not a standard feature in Parquet writing mechanisms.

Thus, the statement acknowledging that all records—including duplicates—may persist in the orders table, providing granularity and a complete history of written entries, reflects a more accurate understanding of the behavior of such data storage systems. This captures the essence of how data retention works when integrating