ONLINE CONTESTS system organises contests on various topics. Each contest on a particular topic has a set of 5 questions to be answered, and is sponsored by a company. The following tables are maintained within database by the system :
Trang 1Exercise 1
Q1
ONLINE CONTESTS system organises contests on various topics Each contest on a
particular topic has a set of 5 questions to be answered, and is sponsored by a company
The following tables are maintained within database by the system :
Table : CONTEST Table : COMPANY
contest_cd
contest_des
clos_dt
comp_cd
Contest code
Name and description
Closing date
Sponsoring company code
comp_cd comp_nm address tel_no cont_per
Company code (PK) Company name
Address
Telephone number
Contact person’s name
Table : QUES_ANS Table : CON_ANS
contest_cd
ques1
ans1
ques2
ans2
ques3
ans3
ques4
ans4
ques5
ans5
Contest code
Question 1
Answer 1
Question 2
Answer 2
Question 3
Answer 3
Question 4
Answer 4
Question 5
Answer 5
con_cd contest_cd ans1 ans2 ans3 ans4 ans5
Contestant code
Contest code
Answer 1
Answer 2
Answer 3
Answer 4
Answer 5
Table : CONTESTANT
Column Description
con_cd
con_nm
e_mail
dt_of_entry
Contestant code
Contestant name
E-mail address
Date of entry
a) Create tables CONTEST, COMPANY, QUES_ANS, CON_ANS, and CONTESTANT b) In COMPANY table, column comp_cd, system generated sequential values like
1000,1002,1004,1006, … will be added at the time of record addition
c) Add few required records to those tables
Notice: PK: Primary key
Trang 2Q2
Use the tables in Question 1 to state T-SQL command / query for each of the following:
a) Set the foreign key constraint for the company code in the CONTEST table
b) Display the unique names of contestants having “hotmail.com” or “yahoo.com” as part of their e-mail address
c) Display the details of contests having closing date as 31st August ’2001, which have not been attempted by any contestant
d) Remove the details of contests from the CONTEST, QUES-ANS and CON_ANS tables, which had closing date before 1st January ’2001
e) Display Contestcode, contestantcode, contestantname and total no of contestant for each contestcode Display the total no of contestants also for all the contests
f) Create a view MAX_ENTRY that stores the contest details of contests for which more than
5 contestant entries have been received
g) Display the company code, name and number of contests sponsored by the company that has sponsored the highest number of contests
Q3 :
Create a trigger, named trig_Del_CONTEST, which will be invoked when a contest
being deleted from the CONTEST table
Before deletion, the contest_cd, contest_des, comp_cd, dt_of_withdraw will be
stored in a CONTEST_HIST table At the same time it will be deleting all
corresponding records from QUES_ANS and CON_ANS tables
CONTEST_HIST table has the structure as follows :
Table : CONTEST_HIST
Column Description
contest_cd
contest_des
comp_cd
dt_of_withdraw
Contest code
Name and description
Company code Date of deletion