Consider a simple example of renaming a field (column). As in Change Function Declaration (124), I need to find the original declaration of the structure and all the callers of this structure and change them in a single change. The complication, however, is that I also have to transform any data that uses the old field to use the new one. I write a small hunk of code that carries out this transform and store it in version control, together with the code that changes any declared structure and access routines. Then, whenever I need to migrate between two versions of the database, I run all the
...more
