将MySQL数据库中的数据转换成结构略有不同的数据?

I did some research on this and couldn't find many introductory resources for a beginner so I'm looking for a basic understanding here of how the process works. The problem I'm trying to solve is as such: I want to move data from an old database to a new one with a slightly different structure, possibly mutating the data a little bit in the process. Without going into the nitty gritty detail.. what are the general steps involved in doing this?I did some research on this and couldn't find m