Method: Sequel::SQL::Builders#join

Defined in:
lib/sequel/sql.rb

#join(args, joiner = nil) ⇒ Object

Return a Sequel::SQL::StringExpression representing an SQL string made up of the concatenation of the given array’s elements. If an argument is passed, it is used in between each element of the array in the SQL concatenation.

Sequel.join([:a]) # SQL: a
Sequel.join([:a, :b]) # SQL: a || b
Sequel.join([:a, 'b']) # SQL: a || 'b'
Sequel.join(['a', :b], ' ') # SQL: 'a' || ' ' || b

Raises:


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# File 'lib/sequel/sql.rb', line 554

def join(args, joiner=nil)
  raise Error, 'argument to Sequel.join must be an array' unless args.is_a?(Array)
  if joiner
    args = args.zip([joiner]*args.length).flatten
    args.pop
  end

  return SQL::StringExpression.new(:NOOP, '') if args.empty?

  args = args.map do |a|
    case a
    when Symbol, ::Sequel::SQL::Expression, ::Sequel::LiteralString, TrueClass, FalseClass, NilClass
      a
    else
      a.to_s
    end
  end
  SQL::StringExpression.new(:'||', *args)
end