_tier field
edit_tier
field
editWhen performing queries across multiple indexes, it is sometimes desirable to
target indexes held on nodes of a given data tier (data_hot
, data_warm
, data_cold
or data_frozen
).
The _tier
field allows matching on the tier_preference
setting of the index a document was indexed into.
The preferred value is accessible in certain queries :
PUT index_1/_doc/1 { "text": "Document in index 1" } PUT index_2/_doc/2?refresh=true { "text": "Document in index 2" } GET index_1,index_2/_search { "query": { "terms": { "_tier": ["data_hot", "data_warm"] } } }
Typically a query will use a terms
query to list the tiers of interest but you can use
the _tier
field in any query that is rewritten to a term
query, such as the
match
, query_string
, term
, terms
, or simple_query_string
query, as well as prefix
and wildcard
queries. However, it does not support regexp
and fuzzy
queries.
The tier_preference
setting of the index is a comma-delimited list of tier names
in order of preference i.e. the preferred tier for hosting an index is listed first followed
by potentially many fall-back options. Query matching only considers the first preference
(the first value of a list).