Class: Mongoid::Criteria

Inherits:
Object
  • Object
show all
Includes:
Enumerable, Inspectable, Mongoid::Clients::Options, Mongoid::Clients::Sessions, Contextual, Findable, Includable, Marshalable, Modifiable, Options, Queryable, Scopable
Defined in:
lib/mongoid/criteria.rb,
lib/mongoid/criteria/options.rb,
lib/mongoid/criteria/findable.rb,
lib/mongoid/criteria/scopable.rb,
lib/mongoid/criteria/queryable.rb,
lib/mongoid/criteria/includable.rb,
lib/mongoid/criteria/modifiable.rb,
lib/mongoid/criteria/permission.rb,
lib/mongoid/criteria/translator.rb,
lib/mongoid/criteria/marshalable.rb,
lib/mongoid/criteria/queryable/key.rb,
lib/mongoid/criteria/queryable/smash.rb,
lib/mongoid/criteria/queryable/options.rb,
lib/mongoid/criteria/queryable/optional.rb,
lib/mongoid/criteria/queryable/pipeline.rb,
lib/mongoid/criteria/queryable/selector.rb,
lib/mongoid/criteria/queryable/storable.rb,
lib/mongoid/criteria/queryable/macroable.rb,
lib/mongoid/criteria/queryable/mergeable.rb,
lib/mongoid/criteria/queryable/aggregable.rb,
lib/mongoid/criteria/queryable/expandable.rb,
lib/mongoid/criteria/queryable/selectable.rb,
lib/mongoid/criteria/queryable/extensions/set.rb,
lib/mongoid/criteria/queryable/extensions/date.rb,
lib/mongoid/criteria/queryable/extensions/hash.rb,
lib/mongoid/criteria/queryable/extensions/time.rb,
lib/mongoid/criteria/queryable/extensions/array.rb,
lib/mongoid/criteria/queryable/extensions/range.rb,
lib/mongoid/criteria/queryable/extensions/object.rb,
lib/mongoid/criteria/queryable/extensions/regexp.rb,
lib/mongoid/criteria/queryable/extensions/string.rb,
lib/mongoid/criteria/queryable/extensions/symbol.rb,
lib/mongoid/criteria/queryable/extensions/boolean.rb,
lib/mongoid/criteria/queryable/extensions/numeric.rb,
lib/mongoid/criteria/queryable/extensions/date_time.rb,
lib/mongoid/criteria/queryable/extensions/nil_class.rb,
lib/mongoid/criteria/queryable/extensions/big_decimal.rb,
lib/mongoid/criteria/queryable/extensions/time_with_zone.rb

Overview

The Criteria class is the core object needed in Mongoid to retrieve objects from the database. It is a DSL that essentially sets up the selector and options arguments that get passed on to a Mongo::Collection in the Ruby driver. Each method on the Criteria returns self to they can be chained in order to create a readable criterion to be executed against the database.

Defined Under Namespace

Modules: Findable, Includable, Marshalable, Modifiable, Options, Permission, Queryable, Scopable, Translator

Constant Summary collapse

ALLOWED_FROM_HASH_METHODS =

Allowed methods for from_hash to prevent arbitrary method execution. Only query-building methods are allowed, not execution or modification methods.

%i[
  all all_in all_of and any_in any_of asc ascending
  batch_size between
  collation comment cursor_type
  desc descending
  elem_match eq exists extras
  geo_spatial group gt gte
  hint
  in includes
  limit lt lte
  max_distance max_scan max_time_ms merge mod
  ne near near_sphere nin no_timeout none none_of nor not not_in
  offset only or order order_by
  project
  raw read reorder
  scoped skip slice snapshot
  text_search type
  unscoped unwind
  where with_size with_type without
].freeze
CHECK =

Static array used to check with method missing - we only need to ever instantiate once.

[]

Instance Attribute Summary collapse

Attributes included from Modifiable

#create_attrs, #create_attrs Additional attributes to add to the Document upon creation.

Attributes included from Queryable

#aliases, #aliases The aliases., #serializers, #serializers The serializers.

Attributes included from Queryable::Optional

#options, #options The query options.

Attributes included from Queryable::Aggregable

#aggregating, #aggregating Flag for whether or not we are aggregating., #pipeline, #pipeline The aggregation pipeline.

Attributes included from Queryable::Mergeable

#strategy, #strategy The name of the current strategy.

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Mongoid::Clients::Sessions

included

Methods included from Mongoid::Clients::Options

#collection, #collection_name, #mongo_client, #persistence_context, #persistence_context?, #with

Methods included from Scopable

#apply_default_scope, #apply_scope, #remove_scoping, #scoped, #scoped?, #scoping_options, #scoping_options=, #unscoped, #unscoped?, #with_default_scope

Methods included from Modifiable

#build, #create, #create!, #create_with, #find_or_create_by, #find_or_create_by!, #find_or_initialize_by, #first_or_create, #first_or_create!, #first_or_initialize

Methods included from Marshalable

#marshal_dump, #marshal_load

Methods included from Includable

#includes, #inclusions, #inclusions=

Methods included from Findable

#execute_or_raise, #for_ids, #multiple_from_db

Methods included from Queryable

#to_mql

Methods included from Queryable::Optional

#ascending, #batch_size, #collation, #comment, #cursor_type, #descending, forwardables, #hint, #limit, #max_scan, #max_time_ms, #no_timeout, #order_by, #reorder, #skip, #slice, #snapshot

Methods included from Queryable::Macroable

#key

Methods included from Selectable

#atomic_selector

Methods included from Queryable::Aggregable

#aggregating?, #group, #project, #unwind

Methods included from Queryable::Mergeable

#and_with_operator, #intersect, #override, #reset_strategies!, #union

Methods included from Queryable::Storable

#add_field_expression, #add_logical_operator_expression, #add_one_expression, #add_operator_expression

Methods included from Contextual

#context, #load_async

Constructor Details

#initialize(klass) ⇒ Criteria

Initialize the new criteria.

Examples:

Init the new criteria.

Criteria.new(Band)

Parameters:

  • klass (Class)

    The model class.



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# File 'lib/mongoid/criteria.rb', line 327

def initialize(klass)
  @klass = klass
  @embedded = nil
  @none = nil
  klass ? super(klass.aliased_fields, klass.fields, klass.relations, klass.aliased_associations) : super({}, {}, {}, {})
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missingObject (private)

Used for chaining Criteria scopes together in the for of class methods on the Document the criteria is for.

Examples:

Handle method missing.

criteria.method_missing(:name)

Parameters:

  • name (Symbol)

    The method name.

  • *args (Object...)

    The arguments.

Returns:

  • (Object)

    The result of the method call.



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# File 'lib/mongoid/criteria.rb', line 627

ruby2_keywords def method_missing(name, *args, &block)
  if klass.respond_to?(name)
    klass.send(:with_scope, self) do
      klass.send(name, *args, &block)
    end
  elsif CHECK.respond_to?(name)
    return entries.send(name, *args, &block)
  else
    super
  end
end

Instance Attribute Details

#_raw_resultsnil | Hash

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

An internal helper for getting/setting the “raw” flag on a given criteria object.

Returns:

  • (nil | Hash)

    If set, it is a hash with two keys, :raw and :typed, that describe whether raw results should be returned, and whether they ought to be typecast.



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# File 'lib/mongoid/criteria.rb', line 248

def _raw_results
  @_raw_results
end

#associationObject

Returns the value of attribute association.



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# File 'lib/mongoid/criteria.rb', line 101

def association
  @association
end

#embeddedObject

Returns the value of attribute embedded.



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# File 'lib/mongoid/criteria.rb', line 101

def embedded
  @embedded
end

#klassObject

Returns the value of attribute klass.



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# File 'lib/mongoid/criteria.rb', line 101

def klass
  @klass
end

#parent_documentObject

Returns the value of attribute parent_document.



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# File 'lib/mongoid/criteria.rb', line 101

def parent_document
  @parent_document
end

Class Method Details

.from_hash(hash) ⇒ Criteria

Deprecated.

This method is deprecated and will be removed in a future release.

Convert the given hash to a criteria. Will iterate over each keys in the hash which must correspond to an allowed method on a criteria object. The hash can include a “klass” key that specifies the model class for the criteria.

Examples:

Convert the hash to a criteria.

Criteria.from_hash({ klass: Band, where: { name: "Depeche Mode" })

Parameters:

  • hash (Hash)

    The hash to convert.

Returns:

Raises:

  • (ArgumentError)

    If a method is not allowed in from_hash.



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# File 'lib/mongoid/criteria.rb', line 83

def from_hash(hash)
  criteria = Criteria.new(hash.delete(:klass) || hash.delete('klass'))
  hash.each_pair do |method, args|
    method_sym = method.to_sym
    unless ALLOWED_FROM_HASH_METHODS.include?(method_sym)
      raise ArgumentError, "Method '#{method}' is not allowed in from_hash"
    end
    criteria = criteria.public_send(method_sym, args)
  end
  criteria
end

Instance Method Details

#==(other) ⇒ true | false

Note:

This will force a database load when called if an enumerable is passed.

Returns true if the supplied Enumerable or Criteria is equal to the results of this Criteria or the criteria itself.

Parameters:

  • other (Object)

    The other Enumerable or Criteria to compare to.

Returns:

  • (true | false)

    If the objects are equal.



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# File 'lib/mongoid/criteria.rb', line 111

def ==(other)
  return super if other.respond_to?(:selector)
  entries == other
end

#_enumerable_findObject

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/mongoid/criteria.rb', line 26

alias :_enumerable_find :find

#_findable_findObject

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.



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# File 'lib/mongoid/criteria.rb', line 33

alias :_findable_find :find

#as_json(options = nil) ⇒ String

Needed to properly get a criteria back as json

Examples:

Get the criteria as json.

Person.where(:title => "Sir").as_json

Parameters:

  • options (Hash) (defaults to: nil)

    Options to pass through to the serializer.

Returns:

  • (String)

    The JSON string.



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# File 'lib/mongoid/criteria.rb', line 173

def as_json(options = nil)
  entries.as_json(options)
end

#documentsArray<Document>

Get the documents from the embedded criteria.

Examples:

Get the documents.

criteria.documents

Returns:



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# File 'lib/mongoid/criteria.rb', line 183

def documents
  @documents ||= []
end

#documents=(docs) ⇒ Array<Document>

Set the embedded documents on the criteria.

Examples:

Set the documents.

Parameters:

  • docs (Array<Document>)

    The embedded documents.

Returns:

  • (Array<Document>)

    The embedded documents.



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# File 'lib/mongoid/criteria.rb', line 194

def documents=(docs)
  @documents = docs
end

#embedded?true | false

Is the criteria for embedded documents?

Examples:

Is the criteria for embedded documents?

criteria.embedded?

Returns:

  • (true | false)

    If the criteria is embedded.



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# File 'lib/mongoid/criteria.rb', line 204

def embedded?
  !!@embedded
end

#empty_and_chainable?true | false

Is the criteria an empty but chainable criteria?

Examples:

Is the criteria a none criteria?

criteria.empty_and_chainable?

Returns:

  • (true | false)

    If the criteria is a none.



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# File 'lib/mongoid/criteria.rb', line 397

def empty_and_chainable?
  !!@none
end

#extract_idObject

Extract a single id from the provided criteria. Could be in an $and query or a straight _id query.

Examples:

Extract the id.

criteria.extract_id

Returns:

  • (Object)

    The id.



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# File 'lib/mongoid/criteria.rb', line 276

def extract_id
  selector['_id'] || selector[:_id] || selector['id'] || selector[:id]
end

#extras(extras) ⇒ Criteria

Adds a criterion to the Criteria that specifies additional options to be passed to the Ruby driver, in the exact format for the driver.

criteria.extras(:limit => 20, :skip => 40)

Examples:

Add extra params to the criteria.

Parameters:

  • extras (Hash)

    The extra driver options.

Returns:



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# File 'lib/mongoid/criteria.rb', line 289

def extras(extras)
  crit = clone
  crit.options.merge!(extras)
  crit
end

#field_listArray<String>

Get the list of included fields.

Examples:

Get the field list.

criteria.field_list

Returns:

  • (Array<String>)

    The fields.



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# File 'lib/mongoid/criteria.rb', line 301

def field_list
  if options[:fields]
    options[:fields].keys.reject{ |key| key == klass.discriminator_key }
  else
    []
  end
end

#find(*args) {|Object| ... } ⇒ Document | Array<Document> | nil

Note:

Each argument can be an individual id, an array of ids or a nested array. Each array will be flattened.

Finds one or many documents given the provided _id values, or filters the documents in the current scope in the application process space after loading them if needed.

If this method is not given a block, it delegates to Findable#find and finds one or many documents for the provided _id values.

If this method is given a block, it delegates to Enumerable#find and returns the first document of those found by the current Criteria object for which the block returns a truthy value.

Note that the “default proc” argument of Enumerable is not specially treated by Mongoid - the decision between delegating to Findable vs Enumerable is made solely based on whether find is passed a block.

Examples:

Finds a document by its _id, invokes Findable#find.

criteria.find("1234")

Finds the first matching document using a block, invokes Enumerable#find.

criteria.find { |item| item.name == "Depeche Mode" }

Finds the first matching document using a block using the default Proc, invokes Enumerable#find.

criteria.find(-> { "Default Band" }) { |item| item.name == "Milwaukee Mode" }

Tries to find a document whose _id is the stringification of the provided Proc, typically failing.

enumerator = criteria.find(-> { "Default Band" })

Parameters:

  • *args ([ Object | Array<Object> ]...)

    The id(s).

  • &block

    Optional block to pass.

Yields:

  • (Object)

    Yields each enumerable element to the block.

Returns:

Raises:

  • Errors::DocumentNotFound If the parameters were _id values and not all documents are found and the raise_not_found_error Mongoid configuration option is truthy.

See Also:



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# File 'lib/mongoid/criteria.rb', line 157

def find(*args, &block)
  if block_given?
    _enumerable_find(*args, &block)
  else
    _findable_find(*args)
  end
end

#for_js(javascript, scope = {}) ⇒ Criteria

Deprecated.

Find documents by the provided javascript and scope. Uses a $where but is different from Criteria#where in that it will pass a code object to the query instead of a pure string. Safe against Javascript injection attacks.

Examples:

Find by javascript.

Band.for_js("this.name = param", param: "Tool")

Parameters:

  • javascript (String)

    The javascript to execute in the $where.

  • scope (Hash) (defaults to: {})

    The scope for the code.

Returns:



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# File 'lib/mongoid/criteria.rb', line 562

def for_js(javascript, scope = {})
  code = if scope.empty?
    # CodeWithScope is not supported for $where as of MongoDB 4.4
    BSON::Code.new(javascript)
  else
    BSON::CodeWithScope.new(javascript, scope)
  end
  js_query(code)
end

#freezeCriteria

When freezing a criteria we need to initialize the context first otherwise the setting of the context on attempted iteration will raise a runtime error.

Examples:

Freeze the criteria.

criteria.freeze

Returns:



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# File 'lib/mongoid/criteria.rb', line 317

def freeze
  context and inclusions and super
end

#merge(other) ⇒ Criteria

Merges another object with this Criteria and returns a new criteria. The other object may be a Criteria or a Hash. This is used to combine multiple scopes together, where a chained scope situation may be desired.

Examples:

Merge the criteria with another criteria.

criteria.merge(other_criteria)

Merge the criteria with a hash. The hash must contain a klass

key that specifies the model class for the criteria and the key/value
pairs correspond to method names/args.

criteria.merge({
  klass: Band,
  where: { name: "Depeche Mode" },
  order_by: { name: 1 }
})

Parameters:

  • other (Criteria | Hash)

    The other criterion to merge with.

Returns:



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# File 'lib/mongoid/criteria.rb', line 355

def merge(other)
  crit = clone
  crit.merge!(other)
  crit
end

#merge!(other) ⇒ Criteria

Merge the other criteria into this one.

Examples:

Merge another criteria into this criteria.

criteria.merge(Person.where(name: "bob"))

Parameters:

  • other (Criteria | Hash)

    The criteria to merge in.

Returns:



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# File 'lib/mongoid/criteria.rb', line 369

def merge!(other)
  other = self.class.from_hash(other) if other.is_a?(Hash)
  selector.merge!(other.selector)
  options.merge!(other.options)
  self.documents = other.documents.dup unless other.documents.empty?
  self.scoping_options = other.scoping_options
  self.inclusions = (inclusions + other.inclusions).uniq
  self._raw_results = self._raw_results || other._raw_results
  self
end

#noneCriteria

Returns a criteria that will always contain zero results and never hits the database.

Examples:

Return a none criteria.

criteria.none

Returns:



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# File 'lib/mongoid/criteria.rb', line 387

def none
  @none = true and self
end

#only(*args) ⇒ Criteria

Overridden to include _type in the fields.

Examples:

Limit the fields returned from the database.

Band.only(:name)

Parameters:

  • *args ([ Symbol | Array<Symbol> ]...)

    The field name(s).

Returns:



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# File 'lib/mongoid/criteria.rb', line 409

def only(*args)
  args = args.flatten
  return clone if args.empty?
  if (args & Fields::IDS).empty?
    args.unshift(:_id)
  end
  if klass.hereditary?
    args.push(klass.discriminator_key.to_sym)
  end
  super(*args)
end

#raw(raw_results = true, typed: nil) ⇒ Criteria

Produce a clone of the current criteria object with it’s “raw” setting set to the given value. A criteria set to “raw” will return all results as raw hashes. If typed is true, the values in the hashes will be typecast according to the fields that they correspond to.

When “raw” is not set (or if raw_results is false), the criteria will return all results as instantiated Document instances.

Examples:

Return query results as raw hashes:

Person.where(city: 'Boston').raw

Parameters:

  • raw_results (true | false) (defaults to: true)

    Whether the new criteria should be placed in “raw” mode or not.

  • typed (true | false) (defaults to: nil)

    Whether the raw results should be typecast before being returned. Default is true if raw_results is false, and false otherwise.

Returns:

  • (Criteria)

    the cloned criteria object.



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# File 'lib/mongoid/criteria.rb', line 226

def raw(raw_results = true, typed: nil)
  # default for typed is true when raw_results is false, and false when
  # raw_results is true.
  typed = !raw_results if typed.nil?

  if !typed && !raw_results
    raise ArgumentError, 'instantiated results must be typecast'
  end

  clone.tap do |criteria|
    criteria._raw_results = { raw: raw_results, typed: typed }
  end
end

#raw_results?true | false

Predicate that answers the question: is this criteria object currently in raw mode? (See #raw for a description of raw mode.)

Returns:

  • (true | false)

    whether the criteria is in raw mode or not.



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# File 'lib/mongoid/criteria.rb', line 254

def raw_results?
  _raw_results && _raw_results[:raw]
end

#read(value = nil) ⇒ Criteria

Set the read preference for the criteria.

Examples:

Set the read preference.

criteria.read(mode: :primary_preferred)

Parameters:

  • value (Hash) (defaults to: nil)

    The mode preference.

Returns:



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# File 'lib/mongoid/criteria.rb', line 429

def read(value = nil)
  clone.tap do |criteria|
    criteria.options.merge!(read: value)
  end
end

#respond_to?(name, include_private = false) ⇒ true | false

Returns true if criteria responds to the given method.

Examples:

Does the criteria respond to the method?

criteria.respond_to?(:each)

Parameters:

  • name (Symbol)

    The name of the class method on the Document.

  • include_private (true | false) (defaults to: false)

    Whether to include privates.

Returns:

  • (true | false)

    If the criteria responds to the method.



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# File 'lib/mongoid/criteria.rb', line 457

def respond_to?(name, include_private = false)
  super || klass.respond_to?(name) || CHECK.respond_to?(name, include_private)
end

#to_criteriaCriteria

Deprecated.

Convenience for objects that want to be merged into a criteria.

Examples:

Convert to a criteria.

criteria.to_criteria

Returns:



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# File 'lib/mongoid/criteria.rb', line 470

def to_criteria
  self
end

#to_procProc

Convert the criteria to a proc.

Examples:

Convert the criteria to a proc.

criteria.to_proc

Returns:

  • (Proc)

    The wrapped criteria.



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# File 'lib/mongoid/criteria.rb', line 481

def to_proc
  ->{ self }
end

#type(types) ⇒ Criteria

Adds a criterion to the Criteria that specifies a type or an Array of types that must be matched.

Examples:

Match only specific models.

criteria.type('Browser')
criteria.type(['Firefox', 'Browser'])

Parameters:

  • types (Array<String>)

    The types to match against.

Returns:



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# File 'lib/mongoid/criteria.rb', line 495

def type(types)
  any_in(self.discriminator_key.to_sym => Array(types))
end

#typecast_results?true | false

Predicate that answers the question: should the results returned by this criteria object be typecast? (See #raw for a description of this.) The answer is meaningless unless #raw_results? is true, since if instantiated document objects are returned they will always be typecast.

Returns:

  • (true | false)

    whether the criteria should return typecast results.



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# File 'lib/mongoid/criteria.rb', line 265

def typecast_results?
  _raw_results && _raw_results[:typed]
end

#where(*args) ⇒ Criteria

This is the general entry point for most MongoDB queries. This either creates a standard field: value selection, and expanded selection with the use of hash methods, or a $where selection if a string is provided.

Examples:

Add a standard selection.

criteria.where(name: "syd")

Add a javascript selection.

criteria.where("this.name == 'syd'")

Parameters:

  • *args ([ Hash | String ]...)

    The standard selection or javascript string.

Returns:

Raises:

  • (UnsupportedJavascript)

    If provided a string and the criteria is embedded.



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# File 'lib/mongoid/criteria.rb', line 516

def where(*args)
  # Historically this method required exactly one argument.
  # As of https://jira.mongodb.org/browse/MONGOID-4804 it also accepts
  # zero arguments.
  # The underlying where implementation that super invokes supports
  # any number of arguments, but we don't presently allow multiple
  # arguments through this method. This API can be reconsidered in the
  # future.
  if args.length > 1
    raise ArgumentError, "Criteria#where requires zero or one arguments (given #{args.length})"
  end
  if args.length == 1
    expression = args.first
    if expression.is_a?(::String) && embedded?
      raise Errors::UnsupportedJavascript.new(klass, expression)
    end
  end
  super
end

#without(*args) ⇒ Criteria

Overridden to exclude _id from the fields.

Examples:

Exclude fields returned from the database.

Band.without(:name)

Parameters:

  • *args (Symbol...)

    The field name(s).

Returns:



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# File 'lib/mongoid/criteria.rb', line 443

def without(*args)
  args -= id_fields
  super(*args)
end

#without_optionsCriteria

Get a version of this criteria without the options.

Examples:

Get the criteria without options.

criteria.without_options

Returns:



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# File 'lib/mongoid/criteria.rb', line 542

def without_options
  crit = clone
  crit.options.clear
  crit
end