For the view of Exercise 4.18, explain why the database system would not allow a tuple to be inserted into the database through this view.
For reference
For the database of Figure 4.12, write a query to find the ID of each employee with no manager. Note that an employee may simply have no manager listed or may have a null manager. Write your query using an outer join and then write it again using no outer join at all.
OUTER JOIN
select e.ID from employee e left outer join manages m on e.ID = m.ID
where m.manager_id is null;
NO OUTER
select e.ID from employee e where e.ID not in (select m.ID from manages m) or e.ID in (select m.ID from manages m where m.manager_id is null);
The Appalachian Mountains
Answer:
Agentless NAC
Explanation:
An active directory is a kind of storage service that holds data of objects like user credentials, resource location etc, for permission and network access authentication.
Network access control is a form of computer network security that integrates security technology like antivirus, intrusion detection and prevention systems etc to system authorisation and authentication processes to control access to a network.
An agentless network access control uses the active directory to scan devices to confirm its compliance to security policies.
i am sup by the way. so im guessing i win?
Answer:
Case-based reasoning.
Explanation:
A database management system (DBMS) can be defined as a collection of software applications that typically enables computer users to create, store, modify, retrieve and manage data or informations in a database. Generally, it allows computer users to efficiently retrieve and manage their data with an appropriate level of security.
A data dictionary can be defined as a centralized collection of information on a specific data such as attributes, names, fields and definitions that are being used in a computer database system.
In a data dictionary, data elements are combined into records, which are meaningful combinations of data elements that are included in data flows or retained in data stores.
This ultimately implies that, a data dictionary found in a computer database system typically contains the records about all the data elements (objects) such as data relationships with other elements, ownership, type, size, primary keys etc. This records are stored and communicated to other data when required or needed.
Basically, when a database management system (DBMS) receives data update requests from application programs, it simply instructs the operating system installed on a server to provide the requested data or informations.
Case-based reasoning is a problem-solving technique where each problem in a database is stored with a description and keywords that identify it. It is typically based on cognitive science and artificial intelligence.
