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:
def validateCreditCard(x):
if type(x)==str and len(x) == 8:
print("Valid credit card number")
else:
print("Invalid credit card number")
validateCreditCard("43589795")
Explanation:
Run the code on your text editor(vs code, sublime, pycharm ) you will get your desired response. If your input is not of type string and not up to 8 digit you will get the response "invalid credit card number" but if it is of type string and up to 8 digit you will get "Valid credit card number".
But remember python works with indentation so when you are transferring this code to your text editor it will run properly well.
I defined the code using the conventional pattern "def"
After defining the function you create a brackets (x) to accommodate your argument x and end it with a semi colon.
Then i use "if" statement to make sure only string argument and 8 digit value will be accepted to print a "valid credit card". if your argument does not pass the if statement condition it will print out the else statement condition which is "Invalid credit card number"
Finally, you have to call your function and test various values.
Answer:
The correct answer is letter "A": controlling.
Explanation:
There are four (4) basic management skills: <em>Planning, Controlling, Organizing, </em>and <em>Leading. </em>
Controlling implies reviewing the objectives the firm has established to evaluate the progress. It also involves measuring the resources the firm has available for reaching its goals and verifying if they will be enough to get to the finish line, otherwise, the company should find more efficient forms of allocating resources and funding its operations.
In other words, <em>the controlling skill of management sets the standards of performance within the institution.</em>
Hey hey hey! I recently took the test and the answer is D | (• ◡•)|
Answer:
you can identify an ip address in the bar where u type links
Explanation:
