Remove all fields from the input stream except those that are specified. Use this processor to prune the input stream, keeping only the fields of interest.
Note: The time field must be specified
explicitly in order to keep it; otherwise you end up with timeless
keep fieldName1, fieldName2,...fieldNameN
||The fields to propagate from input to output||At least one|
Example: Remove all fields except the a field, then log the remaining data points
emit -hz 10 -limit 10 | put a = 1, b = 2 | keep a | view text