Guaranteed properties of many database systems - This is an acronym for Atomicity, Consistency, Isolation, Durability.
In database systems, a consistent transaction is one that does not violate any integrity constraints during its execution
Using a database system such as sqlite or mysql that follows the acid principles is much more easy as the database system guarantees consistency atomicity of the transactions isolation and durability
Updating passwords in a simple password manager
However the isolation part of acid sounds more like consistency model in particular the sequential consistency model
Consistency in Different Context (Distributed System vs Memory Model vs Database)