What does Row Level Security (RLA) control in a database environment?

Row Level Security (RLA) is designed to manage user access at a granular level, specifically on a per-row basis within a database table. This means that it allows for different users or groups of users to see different rows of data based on defined security policies related to their permissions or roles.

The core function of RLA is to enforce security rules that determine which table rows a user is permitted to see or manipulate. This is particularly useful in multi-tenant environments where different users or groups require access to distinct slices of data from the same table, ensuring that sensitive information remains protected and irrelevant to unauthorized users.

In contrast, user access by database schema primarily focuses on broader control over access to entire schemas, which encompasses all objects within that schema rather than the individual rows of data. User access by application pertains to controlling access at the application layer, which does not directly relate to how data is secured within the database structure itself. User access based on roles is more general and could apply to entire database objects such as tables, but it does not specify the finer granularity of the individual rows within those objects.

Thus, the correct understanding of RLA is that it is specifically tailored to manage and control user access at the row level, making the provided