Search multiple data streams and indices [search-multiple-indices]

There are two main methods for searching across multiple data streams and indices in {{es}}:

• Query Level: Directly specify indices in the search request path or use index patterns to target multiple indices.
• Index level: Use index aliases, which act as pointers to one or more backing indices, enabling logical grouping and management of indices.

To search multiple data streams and indices, add them as comma-separated values in the search API's request path.

The following request searches the my-index-000001 and my-index-000002 indices.

GET /my-index-000001,my-index-000002/_search
{
  "query": {
    "match": {
      "user.id": "kimchy"
    }
  }
}

% TEST[setup:my_index] % TEST[s/^/PUT my-index-000002\n/]

You can also search multiple data streams and indices using an index pattern.

The following request targets the my-index-* index pattern. The request searches any data streams or indices in the cluster that start with my-index-.

GET /my-index-*/_search
{
  "query": {
    "match": {
      "user.id": "kimchy"
    }
  }
}

% TEST[setup:my_index]

You can exclude specific indices from a search. The request will retrieve data from all indices starting with my-index-, except for my-index-01.

GET /my-index-*/_search
{
  "query": {
    "bool": {
      "must": [
        {
          "match": {
            "user.id": "kimchy"
          }
        }
      ],
      "must_not": [
        {
          "terms": {
            "_index": ["my-index-01"]
          }
        }
      ]
    }
  }
}

% TEST[setup:my_index]

To search all data streams and indices in a cluster, omit the target from the request path. Alternatively, you can use _all or *.

The following requests are equivalent and search all data streams and indices in the cluster.

GET /_search
{
  "query": {
    "match": {
      "user.id": "kimchy"
    }
  }
}

GET /_all/_search
{
  "query": {
    "match": {
      "user.id": "kimchy"
    }
  }
}

GET /*/_search
{
  "query": {
    "match": {
      "user.id": "kimchy"
    }
  }
}

% TEST[setup:my_index]

Index boost [index-boost]

When searching multiple indices, you can use the indices_boost parameter to boost results from one or more specified indices. This is useful when hits coming from some indices matter more than hits from other.

::::{note} You cannot use indices_boost with data streams. ::::

GET /_search
{
  "indices_boost": [
    { "my-index-000001": 1.4 },
    { "my-index-000002": 1.3 }
  ]
}

% TEST[s/^/PUT my-index-000001\nPUT my-index-000002\n/]

Aliases and index patterns can also be used:

GET /_search
{
  "indices_boost": [
    { "my-alias":  1.4 },
    { "my-index*": 1.3 }
  ]
}

% TEST[s/^/PUT my-index-000001\nPUT my-index-000001/_alias/my-alias\n/]

If multiple matches are found, the first match will be used. For example, if an index is included in alias1 and matches the my-index* pattern, a boost value of 1.4 is applied.