Difference between revisions of "ElasticSearch Query DSL"
| Line 51: | Line 51: | ||
=== bool === | === bool === | ||
| + | |||
| + | The ''bool'' query provides a Boolean combination of queries with typed occurrence: | ||
| + | * '''must''' - clause must appear in matching documents, | ||
| + | * '''should''' - should appear; is no ''must'' clause is provided, at least one ''should'' clause must be matched; you can also specify ''minimum_number_should_match'' parameter, | ||
| + | * '''must_not''' appear. | ||
| + | <pre>{ | ||
| + | "bool" : { | ||
| + | "must" : { | ||
| + | "term" : { "user" : "kimchy" } | ||
| + | }, | ||
| + | "must_not" : { | ||
| + | "range" : { | ||
| + | "age" : { "from" : 10, "to" : 20 } | ||
| + | } | ||
| + | }, | ||
| + | "should" : [ | ||
| + | { | ||
| + | "term" : { "tag" : "wow" } | ||
| + | }, | ||
| + | { | ||
| + | "term" : { "tag" : "elasticsearch" } | ||
| + | } | ||
| + | ], | ||
| + | "minimum_number_should_match" : 1, | ||
| + | "boost" : 1.0 | ||
| + | } | ||
| + | }</pre> | ||
=== boosting === | === boosting === | ||
| + | |||
| + | Boosting can be used to promote or demote search results: | ||
| + | <pre>{ | ||
| + | "boosting" : { | ||
| + | "positive" : { | ||
| + | "term" : { | ||
| + | "field1" : "value1" | ||
| + | } | ||
| + | }, | ||
| + | "negative" : { | ||
| + | "term" : { | ||
| + | "field2" : "value2" | ||
| + | } | ||
| + | }, | ||
| + | "negative_boost" : 0.2 | ||
| + | } | ||
| + | }</pre> | ||
=== ids === | === ids === | ||
| + | |||
| + | Match by ID: | ||
| + | <pre>{ | ||
| + | "ids" : { | ||
| + | "type" : "my_type", | ||
| + | "values" : ["1", "4", "100"] | ||
| + | } | ||
| + | }</pre> | ||
| + | ''Note'': ''type'' field is optional, and may contain array of values. | ||
=== field === | === field === | ||
| + | |||
| + | Query only on a specified field (equivalent of ''query_string'' with ''default_field''): | ||
| + | <pre>{ | ||
| + | "field" : { | ||
| + | "name.first" : "+something -else" | ||
| + | } | ||
| + | }</pre> | ||
=== filtered === | === filtered === | ||
| + | |||
| + | Filters results of a query; may be much faster than querying, as no scoring is done, and may be cached: | ||
| + | <pre>{ | ||
| + | "filtered" : { | ||
| + | "query" : { | ||
| + | "term" : { "tag" : "wow" } | ||
| + | }, | ||
| + | "filter" : { | ||
| + | "range" : { | ||
| + | "age" : { "from" : 10, "to" : 20 } | ||
| + | } | ||
| + | } | ||
| + | } | ||
| + | }</pre> | ||
=== query_string === | === query_string === | ||
Revision as of 12:26, 23 January 2013
ES's Query DSL is a language for specifying queries in JSON.
This is by far not an exhaustive documentation, it's just stuff I use the most; see official documentation for more. Especially the boosting and scoring functionality is not documented here to proper extent.
Contents
Queries
match, multi_match
The match queries accept, analyze, and construct query out of text/numeric/date. The match family of queries does not go through a "query parsing" process. It does not support field name prefixes, wildcard characters, or other "advance" features.
Here, message is name of the field to match in (can be also _all):
{
"match" : {
"message" : "this is a test"
}
}
By default, terms are OR'ed; to AND them:
{
"match" : {
"message" : {
"query" : "this is a test",
"operator" : "and"
}
}
}
To match a phrase:
{
"match_phrase" : {
"message" : "this is a test"
}
}
or using the last word as prefix (the "as you type" search):
{
"match_phrase_prefix" : {
"message" : "this is a test"
}
}
To match in multiple fields, with optional boosting, use:
{
"multi_match" : {
"query" : "this is a test",
"fields" : [ "subject^2", "message" ]
}
}
where matches in subject are "twice as important" as matched in message.
bool
The bool query provides a Boolean combination of queries with typed occurrence:
- must - clause must appear in matching documents,
- should - should appear; is no must clause is provided, at least one should clause must be matched; you can also specify minimum_number_should_match parameter,
- must_not appear.
{
"bool" : {
"must" : {
"term" : { "user" : "kimchy" }
},
"must_not" : {
"range" : {
"age" : { "from" : 10, "to" : 20 }
}
},
"should" : [
{
"term" : { "tag" : "wow" }
},
{
"term" : { "tag" : "elasticsearch" }
}
],
"minimum_number_should_match" : 1,
"boost" : 1.0
}
}
boosting
Boosting can be used to promote or demote search results:
{
"boosting" : {
"positive" : {
"term" : {
"field1" : "value1"
}
},
"negative" : {
"term" : {
"field2" : "value2"
}
},
"negative_boost" : 0.2
}
}
ids
Match by ID:
{
"ids" : {
"type" : "my_type",
"values" : ["1", "4", "100"]
}
}
Note: type field is optional, and may contain array of values.
field
Query only on a specified field (equivalent of query_string with default_field):
{
"field" : {
"name.first" : "+something -else"
}
}
filtered
Filters results of a query; may be much faster than querying, as no scoring is done, and may be cached:
{
"filtered" : {
"query" : {
"term" : { "tag" : "wow" }
},
"filter" : {
"range" : {
"age" : { "from" : 10, "to" : 20 }
}
}
}
}
