Sample a subset of the unique values from the key fields.
Distinct sampling is done by hashing the key and mapping the hash value into buckets matching the inclusion probability. Records having a key mapping to bucket zero are output.
TODO: Add whole line as key.
See Implementation
Sample a subset of the unique values from the key fields.
Distinct sampling is done by hashing the key and mapping the hash value into buckets matching the inclusion probability. Records having a key mapping to bucket zero are output.
TODO: Add whole line as key.