如何在Ruby on Rails 3项目中将YAML数据导入数据库？

I'm now working on a legacy Ruby on Rails project. I found the previous owner of this project exported data from Sqlite3 data tables to separate .yml files. Now I want to import these data from .yml files to their corresponding data tables, but didn't figure out how. The problem can be describe as:I'm now working on a legacy Ruby on Rails proje