# HistogramBarChartResponse
**Source definition:** [`src/bitdrift/public/unary/dashboards/v1/api.proto#L276-L319`]()
| Field | Type | Description |
|---|---|---|
| per_time_series | array of [bitdrift.public.unary.dashboards.v1.HistogramBarChartResponse.PerTimeSeries](#bitdrift.public.unary.dashboards.v1.HistogramBarChartResponse.PerTimeSeries "bitdrift.public.unary.dashboards.v1.HistogramBarChartResponse.PerTimeSeries") | Histogram data for each time series in the chart. |
Example
```json
{
"per_time_series": [
{
"cardinality_overflows": {
"group_by_overflows": 1,
"query_group_by_collapsed": false,
"total_overflows": 42
},
"dimension_names": [
"app_id"
],
"per_group_by": [
{
"buckets": [
{
"begin": 1.0,
"count": 42,
"end": 1.0
}
],
"dimensions": [
"country"
],
"unique_devices": 1
}
],
"title": "Chart title"
}
]
}
```
# HistogramBarChartResponse.Bucket
**Source definition:** [`src/bitdrift/public/unary/dashboards/v1/api.proto#L277-L286`]()
| Field | Type | Description |
|---|---|---|
| begin | double | The beginning of the range for this bucket, inclusive. |
| end | double | The end of the range for this bucket, exclusive. |
| count | uint64 | The count of values that fall within this bucket's range. |
Example
```json
{
"begin": 1.0,
"count": 42,
"end": 1.0
}
```
# HistogramBarChartResponse.PerGroupBy
**Source definition:** [`src/bitdrift/public/unary/dashboards/v1/api.proto#L288-L297`]()
| Field | Type | Description |
|---|---|---|
| dimensions | array of string | The value of the dimension that this group represents. |
| buckets | array of [bitdrift.public.unary.dashboards.v1.HistogramBarChartResponse.Bucket](#bitdrift.public.unary.dashboards.v1.HistogramBarChartResponse.Bucket "bitdrift.public.unary.dashboards.v1.HistogramBarChartResponse.Bucket") | The list of buckets for this histogram bar chart. |
| unique_devices | optional uint64 | The unique devices for the entire table based on the TrackUnique configuration. |
Example
```json
{
"buckets": [
{
"begin": 1.0,
"count": 42,
"end": 1.0
}
],
"dimensions": [
"country"
],
"unique_devices": 1
}
```
# HistogramBarChartResponse.PerTimeSeries
**Source definition:** [`src/bitdrift/public/unary/dashboards/v1/api.proto#L299-L315`]()
| Field | Type | Description |
|---|---|---|
| dimension_names | array of string | Headers for the columns of each group by field (for example, "country", "device_type", etc.). If there are no group by fields this will be empty. |
| title | string | The title of the histogram data, which is derived from the TimeSeries title in the rule chart config. |
| cardinality_overflows | [bitdrift.public.shared.workflows.v1.CardinalityOverflows](bitdrift_public_shared_workflows_v1_CardinalityOverflows.md "bitdrift.public.shared.workflows.v1.CardinalityOverflows") | The total count of cardinality overflows for this time series that occurred during the query time period. |
| per_group_by | array of [bitdrift.public.unary.dashboards.v1.HistogramBarChartResponse.PerGroupBy](#bitdrift.public.unary.dashboards.v1.HistogramBarChartResponse.PerGroupBy "bitdrift.public.unary.dashboards.v1.HistogramBarChartResponse.PerGroupBy") | A set of buckets for every group by combination for this time series. If there are no group by fields, there will be a single entry in this list. |
Example
```json
{
"cardinality_overflows": {
"group_by_overflows": 1,
"query_group_by_collapsed": false,
"total_overflows": 42
},
"dimension_names": [
"app_id"
],
"per_group_by": [
{
"buckets": [
{
"begin": 1.0,
"count": 42,
"end": 1.0
}
],
"dimensions": [
"country"
],
"unique_devices": 1
}
],
"title": "Chart title"
}
```