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);
Answer:
<em> where the attacker secretly relays and possibly alters the communications between two parties who believe that they are directly communicating with each other.</em>
Explanation:
Answer:
The answer is "Procedure"
Explanation:
In the given statement certain information is missing, that is choices, which can be described as follows:
a. procedure
b. software
c. data
d. hardware
e. memory
The procedure is a way, that accomplishes any task in the following steps, if there is a long process so, we divide this process into parts or modules to accomplish the task, and certain alternative was wrong, that can be described as follows:
- Software is a program, that is accomplished in the procedure.
- data, It describes all procedures.
- hardware, It is a device, in which we work.
- memory, It stores all the data in a procedure.
Answer:
1.Choose a clear central message 2. Embrace conflict 3.Have a clear structure
Explanation:
Answer:
RPA or Robotic Process Automation allows organizations to automate tasks which human beings were doing across any applications and systems. The purpose of RPA is to transfer the execution of the process from humans to robots.
