was wondering why the key start with payment?

As payment can not exists without employee, so should not the key like 'employee:1:paymnet:1:amount' is more doamin explanation as well?

Also lot of key-value sotres provides a way to query using `like` syntax.

Example(REDIS): if we want ot get all the payments of a employee we can just ask as 'GET employee:1:payment:*'