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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 :
Exercise 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 : COMPANYColumn Description Column Descriptioncontest_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_ANSColumn Description Column Descriptioncontest_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 Q2 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 . tables. Notice: PK: Primary key Q2 Use the tables in Question 1 to state T -SQL command / query for each of the following: a) Set the foreign