﻿---
title: Rollup search limitations in Elasticsearch
description: Learn about the search constraints when querying rolled-up data. While the rollup function is flexible, the nature of summarizing data means there are...
url: https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5117/manage-data/lifecycle/rollup/rollup-search-limitations
products:
  - Elasticsearch
applies_to:
  - Elastic Cloud Serverless: Unavailable
  - Elastic Stack: Generally available
---

# Rollup search limitations in Elasticsearch
<admonition title="Deprecated in 8.11.0.">
  Rollups will be removed in a future version. [Migrate](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5117/manage-data/lifecycle/rollup/migrating-from-rollup-to-downsampling) to [downsampling](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/5117/manage-data/data-store/data-streams/downsampling-time-series-data-stream) instead.
</admonition>

Learn about the search constraints when querying rolled-up data. While the rollup function is flexible, the nature of summarizing data means there are some limitations. Once live data is discarded, some loss of flexibility is inevitable.
This page highlights the major limitations so that you are aware of them.

## Only one rollup index per search

When using the [Rollup search](https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-rollup-rollup-search) endpoint, the `index` parameter accepts one or more indices. These can be a mix of regular, non-rollup indices and rollup indices. However, only one rollup index can be specified. The exact list of rules for the `index` parameter are as follows:
- At least one index/index-pattern must be specified. This can be either a rollup or non-rollup index. Omitting the index parameter, or using `_all`, is not permitted
- Multiple non-rollup indices may be specified
- Only one rollup index may be specified. If more than one are supplied an exception will be thrown
- Index patterns may be used, but if they match more than one rollup index an exception will be thrown.

This limitation is driven by the logic that decides which jobs are the "best" for any given query. If you have ten jobs stored in a single index, which cover the source data with varying degrees of completeness and different intervals, the query needs to determine which set of jobs to actually search. Incorrect decisions can lead to inaccurate aggregation results (for example, over-counting doc counts, or bad metrics). Needless to say, this is a technically challenging piece of code.
To help simplify the problem, we have limited search to one rollup index at a time (which may contain multiple jobs). In the future we may be able to open this up to multiple rollup jobs.

## Can only aggregate what’s been stored

A perhaps obvious limitation, but rollups can only aggregate on data that has been stored in the rollups. If you don’t configure the rollup job to store metrics about the `price` field, you won’t be able to use the `price` field in any query or aggregation.
For example, the `temperature` field in the following query has been stored in a rollup job… but not with an `avg` metric. Which means the usage of `avg` here is not allowed:
```json

{
  "size": 0,
  "aggregations": {
    "avg_temperature": {
      "avg": {
        "field": "temperature"
      }
    }
  }
}
```

The response will tell you that the field and aggregation were not possible, because no rollup jobs were found which contained them:
```json
{
  "error": {
    "root_cause": [
      {
        "type": "illegal_argument_exception",
        "reason": "There is not a rollup job that has a [avg] agg with name [avg_temperature] which also satisfies all requirements of query.",
        "stack_trace": ...
      }
    ],
    "type": "illegal_argument_exception",
    "reason": "There is not a rollup job that has a [avg] agg with name [avg_temperature] which also satisfies all requirements of query.",
    "stack_trace": ...
  },
  "status": 400
}
```


## Interval granularity

Rollups are stored at a certain granularity, as defined by the `date_histogram` group in the configuration. This means you can only search/aggregate the rollup data with an interval that is greater-than or equal to the configured rollup interval.
For example, if data is rolled up at hourly intervals, the [Rollup search](https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-rollup-rollup-search) API can aggregate on any time interval hourly or greater. Intervals that are less than an hour will throw an exception, since the data simply doesn’t exist for finer granularities.
<admonition title="Requests must be multiples of the config">
  Perhaps not immediately apparent, but the interval specified in an aggregation request must be a whole multiple of the configured interval. If the job was configured to rollup on `3d` intervals, you can only query and aggregate on multiples of three (`3d`, `6d`, `9d`, and so on).A non-multiple wouldn’t work, since the rolled up data wouldn’t cleanly "overlap" with the buckets generated by the aggregation, leading to incorrect results.For that reason, an error is thrown if a whole multiple of the configured interval isn’t found.
</admonition>

Because the RollupSearch endpoint can "upsample" intervals, there is no need to configure jobs with multiple intervals (hourly, daily, and so on). It's recommended to configure a single job with the smallest granularity that is needed, and allow the search endpoint to upsample as needed.
That said, if multiple jobs are present in a single rollup index with varying intervals, the search endpoint will identify and use the job(s) with the largest interval to satisfy the search request.

## Limited querying components

The Rollup functionality allows `query`'s in the search request, but with a limited subset of components. The queries currently allowed are:
- Term Query
- Terms Query
- Range Query
- MatchAll Query
- Any compound query (Boolean, Boosting, ConstantScore, and so on)

Furthermore, these queries can only use fields that were also saved in the rollup job as a `group`. If you wish to filter on a keyword `hostname` field, that field must have been configured in the rollup job under a `terms` grouping.
If you attempt to use an unsupported query, or the query references a field that wasn’t configured in the rollup job, an exception will be thrown. We expect the list of support queries to grow over time as more are implemented.

## Timezones

Rollup documents are stored in the timezone of the `date_histogram` group configuration in the job. If no timezone is specified, the default is to rollup timestamps in `UTC`.