[[search-aggregations-bucket-daterange-aggregation]]
=== Date Range

A range aggregation that is dedicated for date values. The main difference between this aggregation and the normal <<search-aggregations-bucket-range-aggregation,range>> aggregation is that the `from` and `to` values can be expressed in Date Math expressions, and it is also possible to specify a date format by which the `from` and `to` response fields will be returned:

Example:

[source,js]
--------------------------------------------------
{
    "aggs": {
        "range": {
            "date_range": {
                "field": "date",
                "format": "MM-yyy",
                "ranges": [
                    { "to": "now-10M/M" },
                    { "from": "now-10M/M" }
                ]
            }
        }
    }
}
--------------------------------------------------

In the example above, we created two range buckets, the first will "bucket" all documents dated prior to 10 months ago and
the second will "bucket" all documents dated since 10 months ago

Response:

[source,js]
--------------------------------------------------
{
    ...

    "aggregations": {
        "range": {
            "buckets": [
                {
                    "to": 1.3437792E+12,
                    "to_as_string": "08-2012",
                    "doc_count": 7
                },
                {
                    "from": 1.3437792E+12,
                    "from_as_string": "08-2012",
                    "doc_count": 2
                }
            ]
        }
    }
}
--------------------------------------------------

[[date-format-pattern]]
==== Date Format/Pattern

NOTE: this information was copied from http://joda-time.sourceforge.net/apidocs/org/joda/time/format/DateTimeFormat.html[JodaDate]

All ASCII letters are reserved as format pattern letters, which are defined as follows:

[options="header"]
|=======
|Symbol |Meaning                |Presentation       |Examples
|G      |era                    |text               |AD
|C      |century of era (>=0)   |number             |20
|Y      |year of era (>=0)      |year               |1996

|x      |weekyear               |year               |1996
|w      |week of weekyear       |number             |27
|e      |day of week            |number             |2
|E      |day of week            |text               |Tuesday; Tue

|y      |year                   |year               |1996
|D      |day of year            |number             |189
|M      |month of year          |month              |July; Jul; 07
|d      |day of month           |number             |10

|a      |halfday of day               |text         |PM
|K      |hour of halfday (0~11)       |number       |0
|h      |clockhour of halfday (1~12)  |number       |12

|H      |hour of day (0~23)           |number       |0
|k      |clockhour of day (1~24)      |number       |24
|m      |minute of hour               |number       |30
|s      |second of minute             |number       |55
|S      |fraction of second           |number       |978

|z      |time zone                    |text         |Pacific Standard Time; PST
|Z      |time zone offset/id          |zone         |-0800; -08:00; America/Los_Angeles

|'      |escape for text              |delimiter
|''     |single quote                 |literal      |'
|=======
 
The count of pattern letters determine the format.

Text:: If the number of pattern letters is 4 or more, the full form is used; otherwise a short or abbreviated form is used if available.

Number:: The minimum number of digits. Shorter numbers are zero-padded to this amount.

Year:: Numeric presentation for year and weekyear fields are handled specially. For example, if the count of 'y' is 2, the year will be displayed as the zero-based year of the century, which is two digits.

Month:: 3 or over, use text, otherwise use number.

Zone:: 'Z' outputs offset without a colon, 'ZZ' outputs the offset with a colon, 'ZZZ' or more outputs the zone id.

Zone names:: Time zone names ('z') cannot be parsed.

Any characters in the pattern that are not in the ranges of ['a'..'z'] and ['A'..'Z'] will be treated as quoted text. For instance, characters like ':', '.', ' ', '#' and '?' will appear in the resulting time text even they are not embraced within single quotes.