I've been working on a SQL dashboard project whereby I modified a template script.
I became stuck on part of the project and asked for help from a senior colleague (on the same level as my manager but I don't report to him).
He made a clumsy mistake of copying and pasting the template over my work. That is, he replaced the file with the template, saved with the same file name, therefore taking the project back to square one*.
Since then, I've put in extra time to bring the project back on track, but I want to know:
How do I approach my senior colleague to ensure that he doesn't make the same mistake again?
* I've investigated the possibility of recovering the old file, but IT have informed me that is not possible.
Edit I appreciate the value of a version control system. We don't have one and I don't have the ability to download anything to my work computer, e.g. git.
For context I asked How to deal with IT help desk that does not acknowledge requests for help? which highlighted that my employer is very process driven, and those processes are imperfect.
If I proposed a version control system today, it would take over a year to be implemented.