在单独的数据库中用旧的SQL表更新新的SQL表

Question

I have limited experience with Ruby and Active Record, so this is a little tough for me. I need to update a new table in a new database with information still contained in the old table of an old database. I cannot connect to both databases at the same time.

My thinking is to write a script to grab the information from the old database and dump it to a text file ( text1 ). Then manually switch databases and do the same thing on the new database ( text2 ). Then I will compare both text files to output the differences in a new text file ( text3 ). And finally, I will somehow upload this to the new database. That is my pseudocode, at least.

Does anyone have any suggestions or example scripts of how to do this? How do I eventually convert the final text file ( text3 ) into an array or datatype that I will be able to use to update the new database table?

I understand this is a fairly general question, but I would really appreciate the help. Examples are great, information is great, resources are great, just anything to help me figure this out.

Answer 1

Rails provides ability to connect to multiple databases, so I think it would be better to pass data using ActiveRecord than making some operations through text files in your case. All that you need for that is to create settings files and create appropriate models. More details you can find here Connecting Rails 3.1 with Multiple Databases