$search
$search
The
$search
stage performs a full-text search on the specified field or fields. The field or fields must be covered by an Atlas Search index.
Syntax
A $search
pipeline stage has the following prototype form:
{ $search: { "index": "<index-name>", "<operator-name>"|"<collector-name>": { <operator-specification>|<collector-specification> }, "highlight": { <highlight-options> }, "concurrent": true | false, "count": { <count-options> }, "searchAfter"|"searchBefore": "<encoded-token>", "scoreDetails": true| false, "sort": { <fields-to-sort>: 1 | -1 }, "returnStoredSource": true | false, "tracking": { <tracking-option> } } }
Fields
The $search
stage takes a document with the following fields:
Field | Type | Necessity | Description |
---|---|---|---|
<collector-name> | object | Conditional | Name of the collector to use with the
query. You can provide a document that contains the
collector-specific options as the value for this field. Either
this or <operator-name> is required. |
concurrent | boolean | Optional | Parallelize search across segments on dedicated search
nodes. If you don't have separate search
nodes on your cluster, Atlas Search ignores this flag. If omitted,
defaults to false . To learn more, see Parallelize Query Execution Across Segments. |
count | object | Optional | Document that specifies the count options for
retrieving a count of the results. To learn more, see
Count Atlas Search Results. |
highlight | object | Optional | Document that specifies the highlighting
options for displaying search terms in their original context. |
index | string | Optional | Name of the Atlas Search index to use. If omitted, defaults to
If you name your index Atlas Search doesn't return results if you misspell the index name or if the specified index doesn't already exist on the cluster. |
<operator-name> | object | Conditional | |
returnStoredSource | boolean | Optional | Flag that specifies whether to perform a full document lookup
on the backend database or return only stored source fields
directly from Atlas Search. If omitted, defaults to false . To learn
more, see Return Stored Source Fields. |
searchAfter | string | Optional | Reference point for retrieving results. searchAfter returns
documents starting immediately following the specified reference
point. The reference point must be a Base64-encoded token
generated by the $meta keyword
searchSequenceToken . To learn more, see
Paginate the Results. This field is mutually exclusive
with the searchBefore field. |
searchBefore | string | Optional | Reference point for retrieving results. searchBefore returns
documents starting immediately before the specified reference
point. The reference point must be a Base64-encoded token
generated by the $meta keyword
searchSequenceToken . To learn more, see
Paginate the Results. This field is mutually exclusive
with the searchAfter field. |
scoreDetails | boolean | Optional | Flag that specifies whether to retrieve a detailed breakdown of
the score for the documents in the results. If omitted, defaults
to false . To view the details, you must use the $meta expression in the
$project stage. To learn more, see
Return the Score Details. |
sort | object | Optional | Document that specifies the fields to sort the Atlas Search results by
in ascending or descending order. You can sort by date, number
(integer, float, and double values), and string values. To learn
more, see Sort Atlas Search Results. |
tracking | object | Optional | Document that specifies the tracking
option to retrieve analytics information on the search terms. |
Behavior
$search
must be the first stage of any pipeline it appears
in. $search
cannot be used in:
a
$facet
pipeline stage
Aggregation Variable
$search
returns only the results of your query. The
metadata results of your $search
query are saved in the
$$SEARCH_META
aggregation variable. You can use the
$$SEARCH_META
variable to view the metadata results for your
$search
query.
The $$SEARCH_META
aggregation variable
can be used anywhere after a $search
stage in any pipeline,
but it can't be used after the $lookup
or
$unionWith
stage in any pipeline. Starting in MongoDB 6.0, the $$SEARCH_META
aggregation variable can't be used in any subsequent stage after a
$searchMeta
stage.
Example
Suppose the following index on the sample_mflix.movies
collection.
{ "mappings": { "dynamic": false, "fields": { "released": { "type": "date" } } } }
The following query searches for movies released near September
01, 2011 using the $search
stage. The query includes
a:
$project
stage to exclude all fields in the documents excepttitle
andreleased
.$facet
stage that outputs a:docs
field with an array of the top5
search resultsmeta
field with the value of$$SEARCH_META
variable
db.movies.aggregate([ { "$search": { "near": { "path": "released", "origin": ISODate("2011-09-01T00:00:00.000+00:00"), "pivot": 7776000000 } } }, { $project: { "_id": 0, "title": 1, "released": 1 } }, { "$limit": 5 }, { "$facet": { "docs": [], "meta": [ {"$replaceWith": "$$SEARCH_META"}, {"$limit": 1} ] } } ])
{ "docs" : [ { "title" : "Submarino", "released" : ISODate("2011-09-01T00:00:00Z") }, { "title" : "Devil's Playground", "released" : ISODate("2011-09-01T00:00:00Z") }, { "title" : "Bag It", "released" : ISODate("2011-09-01T00:00:00Z") }, { "title" : "Dos", "released" : ISODate("2011-09-01T00:00:00Z") }, { "title" : "We Were Here", "released" : ISODate("2011-09-01T00:00:00Z") } ], "meta" : [ { "count" : { "lowerBound" : NumberLong(17373) } } ] }
To learn more about the $$SEARCH_META
variable and its usage,
see:
Troubleshooting
If you are experiencing issues with your Atlas Search $search
queries, see Troubleshoot Atlas Search Errors.