Class: Alf::Algebra::Join
- Inherits:
-
Object
- Object
- Alf::Algebra::Join
- Includes:
- Binary, Operator, Relational
- Defined in:
- lib/alf/algebra/operator/join.rb
Instance Attribute Summary
Attributes included from Operator
Instance Method Summary collapse
Methods included from Binary
#common_attributes, #common_heading, included, #left, #right, #with_left, #with_right
Methods included from Relational
Methods included from Support::Registry
#each, #listen, #listeners, #register, #registered
Methods included from Operator
#==, #dup, #hash, included, #initialize, #signature, #to_cog, #to_lispy, #to_relvar, #to_s, #type_check, #with_operands
Methods included from TypeCheck
#joinable_headings!, #no_name_clash!, #same_heading!, #type_check_error!, #valid_ordering!
Methods included from Operand
#attr_list, coerce, #resulting_type, #to_ascii_tree, #to_cog, #to_relation, #type_check
Instance Method Details
#heading ⇒ Object
11 12 13 |
# File 'lib/alf/algebra/operator/join.rb', line 11 def heading @heading ||= left.heading + right.heading end |
#keys ⇒ Object
15 16 17 18 19 20 21 22 23 24 25 |
# File 'lib/alf/algebra/operator/join.rb', line 15 def keys @keys ||= begin keys = [] left.keys.each do |k1| right.keys.each do |k2| keys << (k1 | k2) end end Keys.new keys.uniq end end |