diff --git a/docs/tutorials/tutorial-rollup.md b/docs/tutorials/tutorial-rollup.md index 861baf4999ca..f5e1e82174fd 100644 --- a/docs/tutorials/tutorial-rollup.md +++ b/docs/tutorials/tutorial-rollup.md @@ -82,6 +82,9 @@ Note the following aspects of the ingestion statement: * You create the `bytes` and `packets` metrics, which are summed from their respective input fields. * You also create the `count` metric that records the number of rows that get rolled-up per each row in the datasource. +With rollup, Druid combines rows with identical timestamp and dimension values after the timestamp truncation. +Druid computes and stores the metric values using the specified aggregation function over each set of rolled-up rows. + After the ingestion completes, you can query the data. ## Query the example data @@ -102,7 +105,7 @@ Returns the following: | `2018-01-02T21:33:00.000Z` | `7.7.7.7` | `8.8.8.8` | `100,288` | `2` | `161` | | `2018-01-02T21:35:00.000Z` | `7.7.7.7` | `8.8.8.8` | `2,818` | `1` | `12` | -Notice there are only six rows as opposed to the nine rows in the example data. The next section covers how ingestion with rollup accomplishes this. +Notice there are only six rows as opposed to the nine rows in the example data. In the next section, you explore the components of the rolled-up rows. ## View rollup in action