Class | Mongo::Collection |
In: |
lib/mongo/collection.rb
|
Parent: | Object |
A named collection of documents in a database.
db | [R] | |
hint | [R] | |
name | [R] | |
pk_factory | [R] | |
safe | [R] |
Initialize a collection object.
@param [String, Symbol] name the name of the collection. @param [DB] db a MongoDB database instance.
@option opts [:create_pk] :pk (BSON::ObjectId) A primary key factory to use
other than the default BSON::ObjectId.
@option opts [Boolean, Hash] :safe (false) Set the default safe-mode options
for insert, update, and remove method called on this Collection instance. If no value is provided, the default value set on this instance's DB will be used. This default can be overridden for any invocation of insert, update, or remove.
@option options [:primary, :secondary] :read The default read preference for queries
initiates from this connection object. If +:secondary+ is chosen, reads will be sent to one of the closest available secondary nodes. If a secondary node cannot be located, the read will be sent to the primary. If this option is left unspecified, the value of the read preference for this collection's associated Mongo::DB object will be used.
@raise [InvalidNSName]
if collection name is empty, contains '$', or starts or ends with '.'
@raise [TypeError]
if collection name is not a string or symbol
@return [Collection]
@core collections constructor_details
# File lib/mongo/collection.rb, line 53 def initialize(name, db, opts={}) if db.is_a?(String) && name.is_a?(Mongo::DB) warn "Warning: the order of parameters to initialize a collection have changed. " + "Please specify the collection name first, followed by the db. This will be made permanent" + "in v2.0." db, name = name, db end case name when Symbol, String else raise TypeError, "new_name must be a string or symbol" end name = name.to_s if name.empty? or name.include? ".." raise Mongo::InvalidNSName, "collection names cannot be empty" end if name.include? "$" raise Mongo::InvalidNSName, "collection names must not contain '$'" unless name =~ /((^\$cmd)|(oplog\.\$main))/ end if name.match(/^\./) or name.match(/\.$/) raise Mongo::InvalidNSName, "collection names must not start or end with '.'" end if opts.respond_to?(:create_pk) || !opts.is_a?(Hash) warn "The method for specifying a primary key factory on a Collection has changed.\n" + "Please specify it as an option (e.g., :pk => PkFactory)." pk_factory = opts else pk_factory = nil end @db, @name = db, name @connection = @db.connection @logger = @connection.logger @cache_time = @db.cache_time @cache = Hash.new(0) unless pk_factory @safe = opts.fetch(:safe, @db.safe) if value = opts[:read] Mongo::Support.validate_read_preference(value) else value = @db.read_preference end @read_preference = value.is_a?(Hash) ? value.dup : value end @pk_factory = pk_factory || opts[:pk] || BSON::ObjectId @hint = nil end
Return a sub-collection of this collection by name. If ‘users’ is a collection, then ‘users.comments’ is a sub-collection of users.
@param [String, Symbol] name
the collection to return
@raise [Mongo::InvalidNSName]
if passed an invalid collection name
@return [Collection]
the specified sub-collection
# File lib/mongo/collection.rb, line 126 def [](name) name = "#{self.name}.#{name}" return Collection.new(name, db) if !db.strict? || db.collection_names.include?(name.to_s) raise "Collection #{name} doesn't exist. Currently in strict mode." end
Indicate whether this is a capped collection.
@raise [Mongo::OperationFailure]
if the collection doesn't exist.
@return [Boolean]
# File lib/mongo/collection.rb, line 111 def capped? @db.command({:collstats => @name})['capped'] == 1 end
Get the number of documents in this collection.
@option opts [Hash] :query ({}) A query selector for filtering the documents counted. @option opts [Integer] :skip (nil) The number of documents to skip. @option opts [Integer] :limit (nil) The number of documents to limit.
@return [Integer]
# File lib/mongo/collection.rb, line 850 def count(opts={}) find(opts[:query], :skip => opts[:skip], :limit => opts[:limit]).count(true) end
Create a new index.
@param [String, Array] spec
should be either a single field name or an array of [field name, direction] pairs. Directions should be specified as Mongo::ASCENDING, Mongo::DESCENDING, or Mongo::GEO2D. Note that geospatial indexing only works with versions of MongoDB >= 1.3.3+. Keep in mind, too, that in order to geo-index a given field, that field must reference either an array or a sub-object where the first two values represent x- and y-coordinates. Examples can be seen below. Also note that it is permissible to create compound indexes that include a geospatial index as long as the geospatial index comes first. If your code calls create_index frequently, you can use Collection#ensure_index to cache these calls and thereby prevent excessive round trips to the database.
@option opts [Boolean] :unique (false) if true, this index will enforce a uniqueness constraint. @option opts [Boolean] :background (false) indicate that the index should be built in the background. This
feature is only available in MongoDB >= 1.3.2.
@option opts [Boolean] :drop_dups (nil) If creating a unique index on a collection with pre-existing records,
this option will keep the first document the database indexes and drop all subsequent with duplicate values.
@option opts [Integer] :min (nil) specify the minimum longitude and latitude for a geo index. @option opts [Integer] :max (nil) specify the maximum longitude and latitude for a geo index.
@example Creating a compound index:
@posts.create_index([['subject', Mongo::ASCENDING], ['created_at', Mongo::DESCENDING]])
@example Creating a geospatial index:
@restaurants.create_index([['location', Mongo::GEO2D]]) # Note that this will work only if 'location' represents x,y coordinates: {'location': [0, 50]} {'location': {'x' => 0, 'y' => 50}} {'location': {'latitude' => 0, 'longitude' => 50}}
@example A geospatial index with alternate longitude and latitude:
@restaurants.create_index([['location', Mongo::GEO2D]], :min => 500, :max => 500)
@return [String] the name of the index created.
@core indexes create_index-instance_method
# File lib/mongo/collection.rb, line 480 def create_index(spec, opts={}) opts[:dropDups] = opts[:drop_dups] if opts[:drop_dups] field_spec = parse_index_spec(spec) opts = opts.dup name = opts.delete(:name) || generate_index_name(field_spec) name = name.to_s if name generate_indexes(field_spec, name, opts) name end
Return a list of distinct values for key across all documents in the collection. The key may use dot notation to reach into an embedded object.
@param [String, Symbol, OrderedHash] key or hash to group by. @param [Hash] query a selector for limiting the result set over which to group.
@example Saving zip codes and ages and returning distinct results.
@collection.save({:zip => 10010, :name => {:age => 27}}) @collection.save({:zip => 94108, :name => {:age => 24}}) @collection.save({:zip => 10010, :name => {:age => 27}}) @collection.save({:zip => 99701, :name => {:age => 24}}) @collection.save({:zip => 94108, :name => {:age => 27}}) @collection.distinct(:zip) [10010, 94108, 99701] @collection.distinct("name.age") [27, 24] # You may also pass a document selector as the second parameter # to limit the documents over which distinct is run: @collection.distinct("name.age", {"name.age" => {"$gt" => 24}}) [27]
@return [Array] an array of distinct values.
# File lib/mongo/collection.rb, line 776 def distinct(key, query=nil) raise MongoArgumentError unless [String, Symbol].include?(key.class) command = BSON::OrderedHash.new command[:distinct] = @name command[:key] = key.to_s command[:query] = query @db.command(command)["values"] end
Drop the entire collection. USE WITH CAUTION.
# File lib/mongo/collection.rb, line 548 def drop @db.drop_collection(@name) end
Drop all indexes.
@core indexes
# File lib/mongo/collection.rb, line 540 def drop_indexes @cache = {} # Note: calling drop_indexes with no args will drop them all. @db.drop_index(@name, '*') end
Calls create_index and sets a flag to not do so again for another X minutes. this time can be specified as an option when initializing a Mongo::DB object as options[:cache_time] Any changes to an index will be propogated through regardless of cache time (e.g., a change of index direction)
The parameters and options for this methods are the same as those for Collection#create_index.
@example Call sequence:
Time t: @posts.ensure_index([['subject', Mongo::ASCENDING]) -- calls create_index and sets the 5 minute cache Time t+2min : @posts.ensure_index([['subject', Mongo::ASCENDING]) -- doesn't do anything Time t+3min : @posts.ensure_index([['something_else', Mongo::ASCENDING]) -- calls create_index and sets 5 minute cache Time t+10min : @posts.ensure_index([['subject', Mongo::ASCENDING]) -- calls create_index and resets the 5 minute counter
@return [String] the name of the index.
# File lib/mongo/collection.rb, line 507 def ensure_index(spec, opts={}) now = Time.now.utc.to_i opts[:dropDups] = opts[:drop_dups] if opts[:drop_dups] field_spec = parse_index_spec(spec) name = opts[:name] || generate_index_name(field_spec) name = name.to_s if name if !@cache[name] || @cache[name] <= now generate_indexes(field_spec, name, opts) end # Reset the cache here in case there are any errors inserting. Best to be safe. @cache[name] = now + @cache_time name end
Query the database.
The selector argument is a prototype document that all results must match. For example:
collection.find({"hello" => "world"})
only matches documents that have a key "hello" with value "world". Matches can have other keys *in addition* to "hello".
If given an optional block find will yield a Cursor to that block, close the cursor, and then return nil. This guarantees that partially evaluated cursors will be closed. If given no block find returns a cursor.
@param [Hash] selector
a document specifying elements which must be present for a document to be included in the result set. Note that in rare cases, (e.g., with $near queries), the order of keys will matter. To preserve key order on a selector, use an instance of BSON::OrderedHash (only applies to Ruby 1.8).
@option opts [Array, Hash] :fields field names that should be returned in the result
set ("_id" will be included unless explicity excluded). By limiting results to a certain subset of fields, you can cut down on network traffic and decoding time. If using a Hash, keys should be field names and values should be either 1 or 0, depending on whether you want to include or exclude the given field.
@option opts [:primary, :secondary] :read The default read preference for queries
initiates from this connection object. If +:secondary+ is chosen, reads will be sent to one of the closest available secondary nodes. If a secondary node cannot be located, the read will be sent to the primary. If this option is left unspecified, the value of the read preference for this Collection object will be used.
@option opts [Integer] :skip number of documents to skip from the beginning of the result set @option opts [Integer] :limit maximum number of documents to return @option opts [Array] :sort an array of [key, direction] pairs to sort by. Direction should
be specified as Mongo::ASCENDING (or :ascending / :asc) or Mongo::DESCENDING (or :descending / :desc)
@option opts [String, Array, OrderedHash] :hint hint for query optimizer, usually not necessary if
using MongoDB > 1.1
@option opts [Boolean] :snapshot (false) if true, snapshot mode will be used for this query.
Snapshot mode assures no duplicates are returned, or objects missed, which were preset at both the start and end of the query's execution. For details see http://www.mongodb.org/display/DOCS/How+to+do+Snapshotting+in+the+Mongo+Database
@option opts [Boolean] :batch_size (100) the number of documents to returned by the database per
GETMORE operation. A value of 0 will let the database server decide how many results to returns. This option can be ignored for most use cases.
@option opts [Boolean] :timeout (true) when true, the returned cursor will be subject to
the normal cursor timeout behavior of the mongod process. When +false+, the returned cursor will never timeout. Note that disabling timeout will only work when #find is invoked with a block. This is to prevent any inadvertant failure to close the cursor, as the cursor is explicitly closed when block code finishes.
@option opts [Integer] :max_scan (nil) Limit the number of items to scan on both collection scans and indexed queries.. @option opts [Boolean] :show_disk_loc (false) Return the disk location of each query result (for debugging). @option opts [Boolean] :return_key (false) Return the index key used to obtain the result (for debugging). @option opts [Block] :transformer (nil) a block for tranforming returned documents.
This is normally used by object mappers to convert each returned document to an instance of a class.
@raise [ArgumentError]
if timeout is set to false and find is not invoked in a block
@raise [RuntimeError]
if given unknown options
@core find find-instance_method
# File lib/mongo/collection.rb, line 207 def find(selector={}, opts={}) opts = opts.dup fields = opts.delete(:fields) fields = ["_id"] if fields && fields.empty? skip = opts.delete(:skip) || skip || 0 limit = opts.delete(:limit) || 0 sort = opts.delete(:sort) hint = opts.delete(:hint) snapshot = opts.delete(:snapshot) batch_size = opts.delete(:batch_size) timeout = (opts.delete(:timeout) == false) ? false : true max_scan = opts.delete(:max_scan) return_key = opts.delete(:return_key) transformer = opts.delete(:transformer) show_disk_loc = opts.delete(:show_disk_loc) read = opts.delete(:read) || @read_preference if timeout == false && !block_given? raise ArgumentError, "Collection#find must be invoked with a block when timeout is disabled." end if hint hint = normalize_hint_fields(hint) else hint = @hint # assumed to be normalized already end raise RuntimeError, "Unknown options [#{opts.inspect}]" unless opts.empty? cursor = Cursor.new(self, { :selector => selector, :fields => fields, :skip => skip, :limit => limit, :order => sort, :hint => hint, :snapshot => snapshot, :timeout => timeout, :batch_size => batch_size, :transformer => transformer, :max_scan => max_scan, :show_disk_loc => show_disk_loc, :return_key => return_key, :read => read }) if block_given? yield cursor cursor.close nil else cursor end end
Atomically update and return a document using MongoDB‘s findAndModify command. (MongoDB > 1.3.0)
@option opts [Hash] :query ({}) a query selector document for matching the desired document. @option opts [Hash] :update (nil) the update operation to perform on the matched document. @option opts [Array, String, OrderedHash] :sort ({}) specify a sort option for the query using any
of the sort options available for Cursor#sort. Sort order is important if the query will be matching multiple documents since only the first matching document will be updated and returned.
@option opts [Boolean] :remove (false) If true, removes the the returned document from the collection. @option opts [Boolean] :new (false) If true, returns the updated document; otherwise, returns the document
prior to update.
@return [Hash] the matched document.
@core findandmodify find_and_modify-instance_method
# File lib/mongo/collection.rb, line 566 def find_and_modify(opts={}) cmd = BSON::OrderedHash.new cmd[:findandmodify] = @name cmd.merge!(opts) cmd[:sort] = Mongo::Support.format_order_clause(opts[:sort]) if opts[:sort] @db.command(cmd)['value'] end
Return a single object from the database.
@return [OrderedHash, Nil]
a single document or nil if no result is found.
@param [Hash, ObjectId, Nil] spec_or_object_id a hash specifying elements
which must be present for a document to be included in the result set or an instance of ObjectId to be used as the value for an _id query. If nil, an empty selector, {}, will be used.
@option opts [Hash]
any valid options that can be send to Collection#find
@raise [TypeError]
if the argument is of an improper type.
# File lib/mongo/collection.rb, line 277 def find_one(spec_or_object_id=nil, opts={}) spec = case spec_or_object_id when nil {} when BSON::ObjectId {:_id => spec_or_object_id} when Hash spec_or_object_id else raise TypeError, "spec_or_object_id must be an instance of ObjectId or Hash, or nil" end find(spec, opts.merge(:limit => -1)).next_document end
Perform a group aggregation.
@param [Hash] opts the options for this group operation. The minimum required are :initial
and :reduce.
@option opts [Array, String, Symbol] :key (nil) Either the name of a field or a list of fields to group by (optional). @option opts [String, BSON::Code] :keyf (nil) A JavaScript function to be used to generate the grouping keys (optional). @option opts [String, BSON::Code] :cond ({}) A document specifying a query for filtering the documents over
which the aggregation is run (optional).
@option opts [Hash] :initial the initial value of the aggregation counter object (required). @option opts [String, BSON::Code] :reduce (nil) a JavaScript aggregation function (required). @option opts [String, BSON::Code] :finalize (nil) a JavaScript function that receives and modifies
each of the resultant grouped objects. Available only when group is run with command set to true.
@return [Array] the command response consisting of grouped items.
# File lib/mongo/collection.rb, line 651 def group(opts, condition={}, initial={}, reduce=nil, finalize=nil) if opts.is_a?(Hash) return new_group(opts) else warn "Collection#group no longer take a list of parameters. This usage is deprecated and will be remove in v2.0." + "Check out the new API at http://api.mongodb.org/ruby/current/Mongo/Collection.html#group-instance_method" end reduce = BSON::Code.new(reduce) unless reduce.is_a?(BSON::Code) group_command = { "group" => { "ns" => @name, "$reduce" => reduce, "cond" => condition, "initial" => initial } } if opts.is_a?(Symbol) raise MongoArgumentError, "Group takes either an array of fields to group by or a JavaScript function" + "in the form of a String or BSON::Code." end unless opts.nil? if opts.is_a? Array key_type = "key" key_value = {} opts.each { |k| key_value[k] = 1 } else key_type = "$keyf" key_value = opts.is_a?(BSON::Code) ? opts : BSON::Code.new(opts) end group_command["group"][key_type] = key_value end finalize = BSON::Code.new(finalize) if finalize.is_a?(String) if finalize.is_a?(BSON::Code) group_command['group']['finalize'] = finalize end result = @db.command(group_command) if Mongo::Support.ok?(result) result["retval"] else raise OperationFailure, "group command failed: #{result['errmsg']}" end end
Set a hint field for query optimizer. Hint may be a single field name, array of field names, or a hash (preferably an [OrderedHash]). If using MongoDB > 1.1, you probably don‘t ever need to set a hint.
@param [String, Array, OrderedHash] hint a single field, an array of
fields, or a hash specifying fields
# File lib/mongo/collection.rb, line 139 def hint=(hint=nil) @hint = normalize_hint_fields(hint) self end
Insert one or more documents into the collection.
@param [Hash, Array] doc_or_docs
a document (as a hash) or array of documents to be inserted.
@return [ObjectId, Array]
The _id of the inserted document or a list of _ids of all inserted documents.
@option opts [Boolean, Hash] :safe (false)
run the operation in safe mode, which run a getlasterror command on the database to report any assertion. In addition, a hash can be provided to run an fsync and/or wait for replication of the insert (>= 1.5.1). Safe options provided here will override any safe options set on this collection, its database object, or the current connection. See the options on for DB#get_last_error.
@option opts [Boolean] :continue_on_error (false) If true, then
continue a bulk insert even if one of the documents inserted triggers a database assertion (as in a duplicate insert, for instance). MongoDB v2.0+.
@core insert insert-instance_method
# File lib/mongo/collection.rb, line 339 def insert(doc_or_docs, opts={}) doc_or_docs = [doc_or_docs] unless doc_or_docs.is_a?(Array) doc_or_docs.collect! { |doc| @pk_factory.create_pk(doc) } safe = opts.fetch(:safe, @safe) result = insert_documents(doc_or_docs, @name, true, safe, opts) result.size > 1 ? result : result.first end
Perform a map-reduce operation on the current collection.
@param [String, BSON::Code] map a map function, written in JavaScript. @param [String, BSON::Code] reduce a reduce function, written in JavaScript.
@option opts [Hash] :query ({}) a query selector document, like what‘s passed to find, to limit
the operation to a subset of the collection.
@option opts [Array] :sort ([]) an array of [key, direction] pairs to sort by. Direction should
be specified as Mongo::ASCENDING (or :ascending / :asc) or Mongo::DESCENDING (or :descending / :desc)
@option opts [Integer] :limit (nil) if passing a query, number of objects to return from the collection. @option opts [String, BSON::Code] :finalize (nil) a javascript function to apply to the result set after the
map/reduce operation has finished.
@option opts [String] :out (nil) a valid output type. In versions of MongoDB prior to v1.7.6,
this option takes the name of a collection for the output results. In versions 1.7.6 and later, this option specifies the output type. See the core docs for available output types.
@option opts [Boolean] :keeptemp (false) if true, the generated collection will be persisted. The defualt
is false. Note that this option has no effect is versions of MongoDB > v1.7.6.
@option opts [Boolean ] :verbose (false) if true, provides statistics on job execution time. @option opts [Boolean] :raw (false) if true, return the raw result object from the map_reduce command, and not
the instantiated collection that's returned by default. Note if a collection name isn't returned in the map-reduce output (as, for example, when using :out => { :inline => 1 }), then you must specify this option or an ArgumentError will be raised.
@return [Collection, Hash] a Mongo::Collection object or a Hash with the map-reduce command‘s results.
@raise ArgumentError if you specify { :out => { :inline => true }} but don‘t specify :raw => true.
@see www.mongodb.org/display/DOCS/MapReduce Offical MongoDB map/reduce documentation.
@core mapreduce map_reduce-instance_method
# File lib/mongo/collection.rb, line 605 def map_reduce(map, reduce, opts={}) map = BSON::Code.new(map) unless map.is_a?(BSON::Code) reduce = BSON::Code.new(reduce) unless reduce.is_a?(BSON::Code) raw = opts.delete(:raw) hash = BSON::OrderedHash.new hash['mapreduce'] = self.name hash['map'] = map hash['reduce'] = reduce hash.merge! opts if hash[:sort] hash[:sort] = Mongo::Support.format_order_clause(hash[:sort]) end result = @db.command(hash) unless Mongo::Support.ok?(result) raise Mongo::OperationFailure, "map-reduce failed: #{result['errmsg']}" end if raw result elsif result["result"] @db[result["result"]] else raise ArgumentError, "Could not instantiate collection from result. If you specified " + "{:out => {:inline => true}}, then you must also specify :raw => true to get the results." end end
Return a hash containing options that apply to this collection. For all possible keys and values, see DB#create_collection.
@return [Hash] options that apply to this collection.
# File lib/mongo/collection.rb, line 832 def options @db.collections_info(@name).next_document['options'] end
The value of the read preference. This will be either +:primary+, +:secondary+, or an object representing the tags to be read from.
# File lib/mongo/collection.rb, line 705 def read_preference @read_preference end
Remove all documents from this collection.
@param [Hash] selector
If specified, only matching documents will be removed.
@option opts [Boolean, Hash] :safe (false)
run the operation in safe mode, which will run a getlasterror command on the database to report any assertion. In addition, a hash can be provided to run an fsync and/or wait for replication of the remove (>= 1.5.1). Safe options provided here will override any safe options set on this collection, its database, or the current connection. See the options for DB#get_last_error for more details.
@example remove all documents from the ‘users’ collection:
users.remove users.remove({})
@example remove only documents that have expired:
users.remove({:expire => {"$lte" => Time.now}})
@return [Hash, true] Returns a Hash containing the last error object if running in safe mode.
Otherwise, returns true.
@raise [Mongo::OperationFailure] an exception will be raised iff safe mode is enabled
and the operation fails.
@core remove remove-instance_method
# File lib/mongo/collection.rb, line 374 def remove(selector={}, opts={}) # Initial byte is 0. safe = opts.fetch(:safe, @safe) message = BSON::ByteBuffer.new("\0\0\0\0") BSON::BSON_RUBY.serialize_cstr(message, "#{@db.name}.#{@name}") message.put_int(0) message.put_binary(BSON::BSON_CODER.serialize(selector, false, true, @connection.max_bson_size).to_s) instrument(:remove, :database => @db.name, :collection => @name, :selector => selector) do if safe @connection.send_message_with_safe_check(Mongo::Constants::OP_DELETE, message, @db.name, nil, safe) else @connection.send_message(Mongo::Constants::OP_DELETE, message) true end end end
Rename this collection.
Note: If operating in auth mode, the client must be authorized as an admin to perform this operation.
@param [String] new_name the new name for this collection
@return [String] the name of the new collection.
@raise [Mongo::InvalidNSName] if new_name is an invalid collection name.
# File lib/mongo/collection.rb, line 796 def rename(new_name) case new_name when Symbol, String else raise TypeError, "new_name must be a string or symbol" end new_name = new_name.to_s if new_name.empty? or new_name.include? ".." raise Mongo::InvalidNSName, "collection names cannot be empty" end if new_name.include? "$" raise Mongo::InvalidNSName, "collection names must not contain '$'" end if new_name.match(/^\./) or new_name.match(/\.$/) raise Mongo::InvalidNSName, "collection names must not start or end with '.'" end @db.rename_collection(@name, new_name) @name = new_name end
Save a document to this collection.
@param [Hash] doc
the document to be saved. If the document already has an '_id' key, then an update (upsert) operation will be performed, and any existing document with that _id is overwritten. Otherwise an insert operation is performed.
@return [ObjectId] the _id of the saved document.
@option opts [Boolean, Hash] :safe (false)
run the operation in safe mode, which run a getlasterror command on the database to report any assertion. In addition, a hash can be provided to run an fsync and/or wait for replication of the save (>= 1.5.1). See the options for DB#error.
@raise [OperationFailure] when :safe mode fails.
# File lib/mongo/collection.rb, line 307 def save(doc, opts={}) if doc.has_key?(:_id) || doc.has_key?('_id') id = doc[:_id] || doc['_id'] update({:_id => id}, doc, :upsert => true, :safe => opts.fetch(:safe, @safe)) id else insert(doc, :safe => opts.fetch(:safe, @safe)) end end
Update one or more documents in this collection.
@param [Hash] selector
a hash specifying elements which must be present for a document to be updated. Note: the update command currently updates only the first document matching the given selector. If you want all matching documents to be updated, be sure to specify :multi => true.
@param [Hash] document
a hash specifying the fields to be changed in the selected document, or (in the case of an upsert) the document to be inserted
@option opts [Boolean] :upsert (false) if true, performs an upsert (update or insert) @option opts [Boolean] :multi (false) update all documents matching the selector, as opposed to
just the first matching document. Note: only works in MongoDB 1.1.3 or later.
@option opts [Boolean] :safe (false)
If true, check that the save succeeded. OperationFailure will be raised on an error. Note that a safe check requires an extra round-trip to the database. Safe options provided here will override any safe options set on this collection, its database object, or the current collection. See the options for DB#get_last_error for details.
@return [Hash, true] Returns a Hash containing the last error object if running in safe mode.
Otherwise, returns true.
@core update update-instance_method
# File lib/mongo/collection.rb, line 417 def update(selector, document, opts={}) # Initial byte is 0. safe = opts.fetch(:safe, @safe) message = BSON::ByteBuffer.new("\0\0\0\0") BSON::BSON_RUBY.serialize_cstr(message, "#{@db.name}.#{@name}") update_options = 0 update_options += 1 if opts[:upsert] update_options += 2 if opts[:multi] message.put_int(update_options) message.put_binary(BSON::BSON_CODER.serialize(selector, false, true).to_s) message.put_binary(BSON::BSON_CODER.serialize(document, false, true, @connection.max_bson_size).to_s) instrument(:update, :database => @db.name, :collection => @name, :selector => selector, :document => document) do if safe @connection.send_message_with_safe_check(Mongo::Constants::OP_UPDATE, message, @db.name, nil, safe) else @connection.send_message(Mongo::Constants::OP_UPDATE, message) end end end