Method: ROM::Relation::Combined#command

Defined in:
lib/rom/relation/combined.rb

#command(type, *args) ⇒ Object

Return a ‘:create` command that can insert data from a nested hash.

This is limited to ‘:create` commands only, because automatic restriction for `:update` commands would be quite complex. It’s possible that in the future support for ‘:update` commands will be added though.

Another limitation is that it can only work when you’re composing parent and its child(ren), which follows canonical hierarchy from your database, so that parents are created first, then their PKs are set as FKs in child tuples. It should be possible to make it work with both directions (parent => child or child => parent), and it would require converting input tuples based on how they depend on each other, which we could do in the future.

Expanding functionality of this method is planned for rom 5.0.

Raises:

  • NotImplementedError when type is not ‘:create`

See Also:

  • Relation#command


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# File 'lib/rom/relation/combined.rb', line 131

def command(type, *args)
  if type == :create
    super
  else
    raise NotImplementedError, "#{self.class}#command doesn't work with #{type.inspect} command type yet"
  end
end