No rhyme or reason as to failure. Just depends on the order of the specs.
~/Desktop/coding_resources/programs/md_notes
21:38:26 davemox@Daves-MacBook-Pro $ bundle exec rspec
...........F.*................................................................*...............................................
Pending:
rake db:migrate -- runs the migrations and then dumbs the structure of the database to db/schema.rb.
rake db:test:prepare -- load the updated (from above rake db:migrate) schema into the test database.
Because rake db:migrate dumps the db structure into schema.rb, you can quickly restore the db using the rake db:schema:load task instead of running all the migrations all over again on a large project. See p143 of Rails 4 In Action.
rake db:test:prepare is similar to rake db:schema:load. It loads the schema into the test database making the fields available on the dev db also available on the test db.
rake db:test:clone is a combination of rake db:schema:dump and rake db:test:load. See this SO post.