What I am curious about is why couldn't they fix it?
At one point the change was made from 6 to 3 bytes, I expect this made the on disk structure incompatible with prior versions. why were they able to make this change but unable to make a later change say from 3 to 4 bytes.
I am not as familiar with mysql but note that postgres major versions are not disk compatible with each other(you have to dump and restore). I expect this is the exact reason. you want a system where it is possible to make changes.
see also: the drama around linux abi changes vs openbsd abi changes.
To meme off of raul julia: openbsd to linux: "For you, the day your abi changed was the most important day of your life. But for us, it was Tuesday."
At one point the change was made from 6 to 3 bytes, I expect this made the on disk structure incompatible with prior versions. why were they able to make this change but unable to make a later change say from 3 to 4 bytes.
I am not as familiar with mysql but note that postgres major versions are not disk compatible with each other(you have to dump and restore). I expect this is the exact reason. you want a system where it is possible to make changes.
see also: the drama around linux abi changes vs openbsd abi changes.
To meme off of raul julia: openbsd to linux: "For you, the day your abi changed was the most important day of your life. But for us, it was Tuesday."