"rake spec" does not work

[aamine]

"rake spec" produces following error message:

% bundle exec rake spec
rake aborted!
Rake tasks not supported by 'redshift' adapter

Tasks: TOP => db:test:load => db:test:purge
(See full trace by running task with --trace)

[lorgio]

in any config/environments/*.rb file you can add

config.active_record.dump_schema_after_migration = false

essentially the rake task fails on :structure_dump

There's no tasks for redshift and it's not registered in
activerecord-4.2.4/lib/active_record/tasks/database_tasks.rb