Specifies whether the Partition, Offset, and Timestamp columns are exposed.

データ型

bool

デフォルト値

true

解説

Apache Kafka messages include three pieces of metadata along with every message. These are the timestamp when the message was produced, what partition it was produced to, and the message's offset within that partition. The 本製品 exposes these as the Timestamp, Partition, and Offset columns.

These columns are available on every table by default, but you can disable this property to hide them. Consider the following points when deciding whether to disable this option:

• There is no performance benefit to hiding these columns. The Apache Kafka protocol sends them every time the 本製品 consumes a message.
• The 本製品 uses the Partition column to restrict SELECTs to specific partitions. For example, to execute SELECT * FROM topic WHERE Partition IN (1, 2) the 本製品 requests messages from only the first two partitions. Without the partition column the 本製品 will always consume messages from all partitions, or whatever partitions are dictated by the current consumer group (if ConsumerGroupId is set).