How to use sqlite for undo / redo functions?

Question

I am writing a C ++ vector drawing application and am considering using sqlite to support my undo / redo function.

Has anyone used sqlite for undo / redo functions? How does it work for you?

Clarification:

I knew about the stack method, I even implemented one application with this approach. The problem I encountered was that after a while it becomes difficult to maintain.

What I meant when using sqlite is that I will bind my entire in-memory data structure to the sqlite database and let sqlite make the difference and revision for me. Speed ​​should not be a problem if I create a database in memory.

It was an idea, and I was wondering if this could work.

Answer 1

It makes sense to use SQLite to undo undo / redo when the SQLite database is an application data file. See the SQLite website for an explanation of how to do this with SQLite triggers.

Answer 2

In principle, the undo / redo function can be implemented using the stack: when the user performs an operation, you push an object on the stack that represents the delta between the state before and after the operation, and when you cancel, you “expand” the delta. Since each operation that the user creates creates a new delta object on the stack, this may be because sqlite is not your choice of technology, because it may be too slow. I would recommend considering just storing the undo / redo information in memory and linearizing it on disk only if you want to save the undo / redo history.

Answer 3

Take a look at the Memento Design Pattern .