It is the responsibility of the database administrator and security administrator to collectively enforce the security policies of an organization.
The three most important factors to check whether the Data is safe or not are :
If a user is updating a field, then this field becomes inaccessible and other users should not be able to view this data. This blocking is only temporary and only to ensure that no user sees any inaccurate data. This is typically handled by the concurrency control mechanism.
Data should only be revealed to authorized users. A database administrator may also deny access to a user request even if the request does not directly access a sensitive data item, on the grounds that the requested data may reveal information about the sensitive data that the user is not authorized to have.
Before granting access, certain external characteristics about the user may also be considered. For example, a user may only be permitted access during working hours. The system may track previous queries to ensure that a combination of queries does not reveal sensitive data. The latter is particularly relevant to statistical database queries.