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BigData / Apache Hudi Interview Questions

What is a HoodieKey in Hudi?

A HoodieKey is the combination of a record key and a partition path that uniquely identifies a single record within a Hudi table. It's the primary mechanism Hudi uses to decide whether an incoming row is a brand-new insert or an update to an existing row.

The record key can be a single column or a composite of several columns, and the partition path determines which physical partition the record's file group lives in. Choosing HoodieKey fields carefully matters a lot — a poor choice can create hot partitions or force expensive global index lookups when a record's partition value can change over time.

A HoodieKey is made up of:
HoodieKey is primarily used to determine:

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