druid/docs/content/querying/timeseriesquery.md

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---
layout: doc_page
---
Timeseries queries
==================
These types of queries take a timeseries query object and return an array of JSON objects where each object represents a value asked for by the timeseries query.
An example timeseries query object is shown below:
```json
{
"queryType": "timeseries",
"dataSource": "sample_datasource",
"granularity": "day",
"descending": "true",
"filter": {
"type": "and",
"fields": [
{ "type": "selector", "dimension": "sample_dimension1", "value": "sample_value1" },
{ "type": "or",
"fields": [
{ "type": "selector", "dimension": "sample_dimension2", "value": "sample_value2" },
{ "type": "selector", "dimension": "sample_dimension3", "value": "sample_value3" }
]
}
]
},
"aggregations": [
{ "type": "longSum", "name": "sample_name1", "fieldName": "sample_fieldName1" },
{ "type": "doubleSum", "name": "sample_name2", "fieldName": "sample_fieldName2" }
],
"postAggregations": [
{ "type": "arithmetic",
"name": "sample_divide",
"fn": "/",
"fields": [
{ "type": "fieldAccess", "name": "postAgg__sample_name1", "fieldName": "sample_name1" },
{ "type": "fieldAccess", "name": "postAgg__sample_name2", "fieldName": "sample_name2" }
]
}
],
"intervals": [ "2012-01-01T00:00:00.000/2012-01-03T00:00:00.000" ]
}
```
There are 7 main parts to a timeseries query:
|property|description|required?|
|--------|-----------|---------|
|queryType|This String should always be "timeseries"; this is the first thing Druid looks at to figure out how to interpret the query|yes|
|dataSource|A String or Object defining the data source to query, very similar to a table in a relational database. See [DataSource](../querying/datasource.html) for more information.|yes|
|descending|Whether to make descending ordered result. Default is `false`(ascending).|no|
|intervals|A JSON Object representing ISO-8601 Intervals. This defines the time ranges to run the query over.|yes|
|granularity|Defines the granularity to bucket query results. See [Granularities](../querying/granularities.html)|yes|
|filter|See [Filters](../querying/filters.html)|no|
|aggregations|See [Aggregations](../querying/aggregations.html)|yes|
|postAggregations|See [Post Aggregations](../querying/post-aggregations.html)|no|
|context|See [Context](../querying/query-context.html)|no|
To pull it all together, the above query would return 2 data points, one for each day between 2012-01-01 and 2012-01-03, from the "sample\_datasource" table. Each data point would be the (long) sum of sample\_fieldName1, the (double) sum of sample\_fieldName2 and the (double) result of sample\_fieldName1 divided by sample\_fieldName2 for the filter set. The output looks like this:
```json
[
{
"timestamp": "2012-01-01T00:00:00.000Z",
"result": { "sample_name1": <some_value>, "sample_name2": <some_value>, "sample_divide": <some_value> }
},
{
"timestamp": "2012-01-02T00:00:00.000Z",
"result": { "sample_name1": <some_value>, "sample_name2": <some_value>, "sample_divide": <some_value> }
}
]
```
#### Zero-filling
Timeseries queries normally fill empty interior time buckets with zeroes. For example, if you issue a "day" granularity
timeseries query for the interval 2012-01-01/2012-01-04, and no data exists for 2012-01-02, you will receive:
```json
[
{
"timestamp": "2012-01-01T00:00:00.000Z",
"result": { "sample_name1": <some_value> }
},
{
"timestamp": "2012-01-02T00:00:00.000Z",
"result": { "sample_name1": 0 }
},
{
"timestamp": "2012-01-03T00:00:00.000Z",
"result": { "sample_name1": <some_value> }
}
]
```
Time buckets that lie completely outside the data interval are not zero-filled.
You can disable all zero-filling with the context flag "skipEmptyBuckets". In this mode, the data point for 2012-01-02
would be omitted from the results.
A query with this context flag set would look like:
```json
{
"queryType": "timeseries",
"dataSource": "sample_datasource",
"granularity": "day",
"aggregations": [
{ "type": "longSum", "name": "sample_name1", "fieldName": "sample_fieldName1" }
],
"intervals": [ "2012-01-01T00:00:00.000/2012-01-04T00:00:00.000" ],
"context" : {
"skipEmptyBuckets": "true"
}
}
```