[[query-dsl-indices-filter]]
=== Indices Filter

The `indices` filter can be used when executed across multiple indices,
allowing to have a filter that executes only when executed on an index
that matches a specific list of indices, and another filter that executes
when it is executed on an index that does not match the listed indices.

[source,js]
--------------------------------------------------
{
    "indices" : {
        "indices" : ["index1", "index2"],
        "filter" : {
            "term" : { "tag" : "wow" }
        },
        "no_match_filter" : {
            "term" : { "tag" : "kow" }
        }
    }
}
--------------------------------------------------

You can use the `index` field to provide a single index.

`no_match_filter` can also have "string" value of `none` (to match no
documents), and `all` (to match all). Defaults to `all`.

`filter` is mandatory, as well as `indices` (or `index`).

[TIP]
===================================================================
The fields order is important: if the `indices` are provided before `filter`
or `no_match_filter`, the related filters get parsed only against the indices
that they are going to be executed on. This is useful to avoid parsing filters
when it is not necessary and prevent potential mapping errors.
===================================================================