Range Filter

Filters documents with fields that have terms within a certain range. Similar to range query, except that it acts as a filter. Can be placed within queries that accept a filter.

{
    "constant_score" : {
        "filter" : {
            "range" : {
                "age" : {
                    "gte": 10,
                    "lte": 20
                }
            }
        }
    }
}

The range filter accepts the following parameters:

gte

Greater-than or equal to

gt

Greater-than

lte

Less-than or equal to

lt

Less-than

Execution

The execution option controls how the range filter internally executes. The execution option accepts the following values:

index

Uses the field’s inverted index in order to determine whether documents fall within the specified range.

fielddata

Uses fielddata in order to determine whether documents fall within the specified range.

In general for small ranges the index execution is faster and for longer ranges the fielddata execution is faster.

The fielddata execution, as the name suggests, uses field data and therefore requires more memory, so make sure you have sufficient memory on your nodes in order to use this execution mode. It usually makes sense to use it on fields you’re already aggregating or sorting by.

Caching

The result of the filter is only automatically cached by default if the execution is set to index. The _cache can be set to false to turn it off.

If the now date math expression is used without rounding then a range filter will never be cached even if _cache is set to true. Also any filter that wraps this filter will never be cached.