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geoSearch
MongoDB 5.0 removes the deprecated geoHaystack index and geoSearch command. Use a 2d index with $geoNear or one of the supported geospatial query operators instead.
Upgrading your MongoDB instance to 5.0 and setting featureCompatibilityVersion to 5.0 will delete any pre-existing geoHaystack indexes.
The geoSearch command provides an interface to MongoDB's haystack index functionality. These indexes are useful for returning results based on location coordinates aftercollecting results based on some other query (i.e. a "haystack.")
The geoSearch command accepts a document that contains the following fields.
geoSearch | string | The collection to query. |
search | document | Query to filter documents. |
near | array | Coordinates of a point. |
maxDistance | number | Optional. Maximum distance from the specified point. |
limit | number | Optional. Maximum number of documents to return. |
readConcern | document |
Starting in MongoDB 3.6, the readConcern option has the following syntax: Possible read concern levels are:
For more formation on the read concern levels, see Read Concern Levels. For more information on the read concern levels, see Read Concern Levels. |
comment | any |
A comment can be any valid BSON type(string, integer, object, array, etc).
|
Unless specified otherwise, the geoSearch command limits results to 50 documents.
geoSearch is not supported for sharded clusters.
geoSearch can be used inside multi-document transactions.
In most cases, multi-document transaction incurs a greater performance cost over single document writes, and the availability of multi-document transactions should not be a replacement for effective schema design. For many scenarios, the denormalized data model (embedded documents and arrays) will continue to be optimal for your data and use cases. That is, for many scenarios, modeling your data appropriately will minimize the need for multi-document transactions.
For additional transactions usage considerations (such as runtime limit and oplog size limit), see also Production Considerations.
Consider the following example:
db.runCommand({
geoSearch : "places",
near: [ -73.9667, 40.78 ],
maxDistance : 6,
search : { type : "restaurant" },
limit : 30
})
The above command returns all documents with a type of restaurant having a maximum distance of 6 units from the coordinates [ -73.9667, 40.78 ] in the collection places up to a maximum of 30 results.
To override the default read concern level of "local", use the readConcern option.
The following operation on a replica set specifies a Read Concern of "majority" to read the most recent copy of the data confirmed as having been written to a majority of the nodes.
Regardless of the read concern level, the most recent data on a node may not reflect the most recent version of the data in the system.
db.runCommand(
{
geoSearch: "places",
near: [ -73.9667, 40.78 ],
search : { type : "restaurant" },
readConcern: { level: "majority" }
}
)
To ensure that a single thread can read its own writes, use "majority" read concern and "majority" write concern against the primary of the replica set.