Class: ROM::SQL::Association

Inherits:
Object
  • Object
show all
Extended by:
Dry::Core::ClassAttributes, Initializer
Includes:
Dry::Core::Constants
Defined in:
lib/rom/sql/association.rb,
lib/rom/sql/association/name.rb,
lib/rom/sql/association/one_to_one.rb,
lib/rom/sql/association/many_to_one.rb,
lib/rom/sql/association/one_to_many.rb,
lib/rom/sql/association/many_to_many.rb,
lib/rom/sql/association/one_to_one_through.rb

Overview

Abstract association class

Direct Known Subclasses

ManyToMany, ManyToOne, OneToMany

Defined Under Namespace

Classes: ManyToMany, ManyToOne, Name, OneToMany, OneToOne, OneToOneThrough

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#as ⇒ Symbol (readonly) Also known as: name

Returns an optional association alias name.

Returns:

  • (Symbol) —

    an optional association alias name



40
 
# File 'lib/rom/sql/association.rb', line 40

option :as, Types::Strict::Symbol, reader: true, optional: true, default: -> assoc { assoc.target.to_sym }

#foreign_key ⇒ Symbol (readonly)

Returns an optional association alias name.

Returns:

  • (Symbol) —

    an optional association alias name



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# File 'lib/rom/sql/association.rb', line 44

option :foreign_key, Types::Strict::Symbol, optional: true, reader: true, default: proc { nil }

#relation ⇒ Symbol (readonly)

Returns an optional relation identifier for the target.

Returns:

  • (Symbol) —

    an optional relation identifier for the target



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# File 'lib/rom/sql/association.rb', line 32

option :relation, Types::Strict::Symbol, reader: true, optional: true

#result ⇒ Symbol (readonly)

Returns either :one or :many.

Returns:

  • (Symbol) —

    either :one or :many



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# File 'lib/rom/sql/association.rb', line 36

option :result, Types::Strict::Symbol, reader: true, default: -> assoc { assoc.class.result }

#source ⇒ ROM::Relation::Name (readonly)

Returns the source relation name.

Returns:

  • (ROM::Relation::Name) —

    the source relation name



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# File 'lib/rom/sql/association.rb', line 24

param :source

#target ⇒ ROM::Relation::Name (readonly)

Returns the target relation name.

Returns:

  • (ROM::Relation::Name) —

    the target relation name



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# File 'lib/rom/sql/association.rb', line 28

param :target

#view ⇒ Symbol (readonly)

Returns An optional view that should be used to extend assoc relation.

Returns:

  • (Symbol) —

    An optional view that should be used to extend assoc relation



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# File 'lib/rom/sql/association.rb', line 48

option :view, reader: true, optional: true, default: proc { nil }

Class Method Details

.new(source, target, options = EMPTY_HASH) ⇒ Object 



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# File 'lib/rom/sql/association.rb', line 53

def self.new(source, target, options = EMPTY_HASH)
  super(
    Name[source],
    Name[options[:relation] || target, target, options[:as] || target],
    options
  )
end

Instance Method Details

#apply_view(schema, relation) ⇒ Object 



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# File 'lib/rom/sql/association.rb', line 82

def apply_view(schema, relation)
  view_rel = relation.public_send(view)
  schema.merge(view_rel.schema.qualified).uniq(&:to_sym).(view_rel)
end

#join(relations, type, source = relations[self.source], target = relations[self.target]) ⇒ Object 



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# File 'lib/rom/sql/association.rb', line 62

def join(relations, type, source = relations[self.source], target = relations[self.target])
  source.__send__(type, target.name.dataset, join_keys(relations)).qualified
end

#join_key_map(relations) ⇒ Object

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/rom/sql/association.rb', line 88

def join_key_map(relations)
  join_keys(relations).to_a.flatten.map(&:to_sym)
end

#qualify(name, attribute) ⇒ QualifiedAttribute

Returns a qualified attribute name for a given dataset

This is compatible with Sequel’s SQL generator and can be used in query DSL methods

Parameters:

  • name (ROM::Relation::Name)
  • attribute (Symbol)

Returns:



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# File 'lib/rom/sql/association.rb', line 77

def qualify(name, attribute)
  QualifiedAttribute[name.to_sym, attribute]
end

#self_ref? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rom/sql/association.rb', line 92

def self_ref?
  source.dataset == target.dataset
end