What is key salting in the context of data processing?
| Term | Description |
|---|---|
| Key Salting | Key salting is a technique used in data processing to manage data skew in distributed systems like Apache Spark. It involves modifying the keys of data records by adding a random value or 'salt' to them. This results in the creation of additional unique keys, which help in distributing the data more evenly across multiple partitions. The primary purpose of key salting is to prevent a few partitions from being overloaded with a large number of similar key values, which can cause performance bottlenecks during operations like shuffling or joining. After processing, the salt can be removed or ignored to obtain the original aggregation results or relationships. |