collection.md

Collection

Methods

collection:aggregate(pipeline, [options], [prefs])

Executes an aggregation pipeline on collection and returns a Cursor handle.

collection:count(query, [options], [prefs])

Executes a count query on collection and returns the result. On error, returns nil and the error message.

collection:createBulkOperation([options])

Returns a new Bulk operation. By default, the operation is ordered (see below). To denote the type of a new bulk operation, set ordered in options to either true or false.

Ordered bulk operations are batched and sent to the server in the order suitable for serial execution. The processing aborts when the first error is encountered.

Unordered bulk operations are batched and sent to the server in arbitrary order where they may be executed in parallel with any errors reported after all operations are attempted.

collection:drop([options])

Drops collection and returns true. On error, returns nil and the error message.

collection:find(query, [options], [prefs])

Executes a find query on collection and returns a Cursor handle.

collection:findAndModify(query, options)

Executes a find-and-modify query on collection and returns a BSON document or nil if nothing was found. On error, returns nil and the error message.

collection:findOne(query, [options], [prefs])

Returns the first BSON document in collection that matches query or nil if nothing was found. On error, returns nil and the error message.

This method is semantically equivalent to:

function collection:findOne(query, options)
    options = options or {}
    options.limit = 1
    options.singleBatch = true
    local cursor = collection:find(query, options)
    return cursor:next()
end

except that it avoids creating a temporary Cursor handle.

collection:getName()

Returns the name of collection.

collection:getReadPrefs()

Returns the default read preferences.

collection:insert(document, [flags])

Inserts document into collection and returns true. On error, returns nil and the error message. See also Flags for insert for information on flags.

If no _id element is found in the document, a new unique BSON ObjectID will be generated locally and added to the document. If you must know the inserted document's _id, generate it in your code and add to the document before calling this method.

collection:insertMany(document1, document2, ...)

Inserts document1, document2, etc. into collection and returns true. On error, returns nil and the error message.

collection:insertOne(document, [options])

Inserts document into collection and returns true. On error, returns nil and the error message.

collection:remove(query, [flags])

Removes documents in collection that match query and returns true. On error, returns nil and the error message. See also Flags for remove for information on flags.

collection:removeMany(query, [options])

Removes all documents in collection that match query and returns true. On error, returns nil and the error message.

collection:removeOne(query, [options])

Removes at most one document in collection that matches query and returns true. On error, returns nil and the error message.

collection:rename(dbname, collname, [force], [options])

Renames collection on the server using new database name dbname and collection name collname. If force is true, an existing collection with the same name will be dropped first.

collection:replaceOne(query, document, [options])

Replaces at most one document in collection that matches query with document and returns true. On error, returns nil and the error message.

collection:setReadPrefs(prefs)

Sets the default read preferences.

collection:update(query, document, [flags])

Updates documents in collection that match query with document and returns true. On error, returns nil and the error message. See also Flags for update for information on flags.

collection:updateMany(query, document, [options])

Updates all documents in collection that match query with document and returns true. On error, returns nil and the error message.

collection:updateOne(query, document, [options])

Updates at most one document in collection that matches query with document and returns true. On error, returns nil and the error message.