anchor.diff:  `histogram`::
   (Optional, <<search-aggregations-bucket-histogram-aggregation,`histogram`
   aggregation>> object)
  -Groups and stores <<number,numeric>> field values based on a provided interval.
  +Groups documents based on a numeric interval.
   +
   .Properties of `histogram`
   [%collapsible%open]
   ======
   `fields`::
   (Required*, string or array of strings)
  -<<number,Numeric>> fields to group. If you specify a `histogram` object, this
  -property is required.
  -+
  -WARNING: Do not use the same fields in `histogram` and `metrics`. If you specify
  -the same field in both `histogram` and `metrics`, the rollup attempt will fail.
  +<<number,Numeric>> fields to group. `unsigned_long` fields are not supported. If
  +you specify a `histogram` object, this property is required.
  ++
  +WARNING: Do not use these fields in `metrics`. If you do, the rollup attempt
  +will fail.
   
   `interval`::
   (Required*, integer)
  
positive.code: <<date,`date`>> or <<date_nanos,`date_nanos`>> field containing a timestamp. If
  you're rolling up a backing index or using the {ecs-ref}[Elastic Common Schema
  (ECS)], we recommend using `@timestamp`.
  
  `calendar_interval` or `fixed_interval`::
  (Required, <<time-units,time units>>)
  
negative.code: 
  * You can only roll up an index that contains:
  
  ** A <<date,`date`>> or <<date_nanos,`date_nanos`>> timestamp field.
  ** At least one metric to roll up. This field must be a <<number,numeric>>,
    `date`, or `date_nanos` field other than the timestamp field. This field
    cannot be an `unsigned_long`.
  
  * If the {es} {security-features} are enabled, you must have the `manage`
  <<privileges-list-indices,index privilege>> for the index you roll up.
  