Class: ActiveRecord::Associations::JoinDependency::JoinPart
- Inherits:
-
Object
- Object
- ActiveRecord::Associations::JoinDependency::JoinPart
- Includes:
- Enumerable
- Defined in:
- lib/active_record/associations/join_dependency/join_part.rb
Overview
A JoinPart represents a part of a JoinDependency. It is inherited by JoinBase and JoinAssociation. A JoinBase represents the Active Record which everything else is being joined onto. A JoinAssociation represents an association which is joining to the base. A JoinAssociation may result in more than one actual join operations (for example a has_and_belongs_to_many JoinAssociation would result in two; one for the join table and one for the target table).
Direct Known Subclasses
Instance Attribute Summary collapse
-
#base_klass ⇒ Object
readonly
The Active Record class which this join part is associated ‘about’; for a JoinBase this is the actual base model, for a JoinAssociation this is the target model of the association.
-
#children ⇒ Object
readonly
The Active Record class which this join part is associated ‘about’; for a JoinBase this is the actual base model, for a JoinAssociation this is the target model of the association.
Instance Method Summary collapse
- #each {|_self| ... } ⇒ Object
- #extract_record(row, column_names_with_alias) ⇒ Object
-
#initialize(base_klass, children) ⇒ JoinPart
constructor
A new instance of JoinPart.
- #instantiate(row, aliases, &block) ⇒ Object
- #match?(other) ⇒ Boolean
-
#table ⇒ Object
An Arel::Table for the active_record.
Constructor Details
#initialize(base_klass, children) ⇒ JoinPart
Returns a new instance of JoinPart.
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# File 'lib/active_record/associations/join_dependency/join_part.rb', line 22 def initialize(base_klass, children) @base_klass = base_klass @children = children end |
Instance Attribute Details
#base_klass ⇒ Object (readonly)
The Active Record class which this join part is associated ‘about’; for a JoinBase this is the actual base model, for a JoinAssociation this is the target model of the association.
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# File 'lib/active_record/associations/join_dependency/join_part.rb', line 18 def base_klass @base_klass end |
#children ⇒ Object (readonly)
The Active Record class which this join part is associated ‘about’; for a JoinBase this is the actual base model, for a JoinAssociation this is the target model of the association.
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# File 'lib/active_record/associations/join_dependency/join_part.rb', line 18 def children @children end |
Instance Method Details
#each {|_self| ... } ⇒ Object
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# File 'lib/active_record/associations/join_dependency/join_part.rb', line 31 def each(&block) yield self children.each { |child| child.each(&block) } end |
#extract_record(row, column_names_with_alias) ⇒ Object
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# File 'lib/active_record/associations/join_dependency/join_part.rb', line 41 def extract_record(row, column_names_with_alias) # This code is performance critical as it is called per row. # see: https://github.com/rails/rails/pull/12185 hash = {} index = 0 length = column_names_with_alias.length while index < length column_name, alias_name = column_names_with_alias[index] hash[column_name] = row[alias_name] index += 1 end hash end |
#instantiate(row, aliases, &block) ⇒ Object
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# File 'lib/active_record/associations/join_dependency/join_part.rb', line 58 def instantiate(row, aliases, &block) base_klass.instantiate(extract_record(row, aliases), &block) end |
#match?(other) ⇒ Boolean
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# File 'lib/active_record/associations/join_dependency/join_part.rb', line 27 def match?(other) self.class == other.class end |
#table ⇒ Object
An Arel::Table for the active_record
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# File 'lib/active_record/associations/join_dependency/join_part.rb', line 37 def table raise NotImplementedError end |