6.

The table Arc(x,y) currently has the following tuples (note there are duplicates): (1,2), (1,2), (2,3), (3,4), (3,4), (4,1), (4,1), (4,1), (4,2). Compute the result of the query: SELECT a1.x, a2.y, COUNT(*) FROM Arc a1, Arc a2 WHERE a1.y = a2.x GROUP BY a1.x, a2.y; Which of the following tuples is in the result?

		a)	(1,2,4)			b)	(1,3,2)			c)	(4,3,3)			d)	(2,1,3)

7.

The table

Scores(Team, Day, Opponent, Runs)

Contains the following 12 rows:

Team	Day	Opponent	Runs
Dragons	Sunday	Swallows	4
Tigers	Sunday	Bay Stars	9
Carp	Sunday	NULL	NULL
Swallows	Sunday	Dragons	7
Bay Stars	Sunday	Tigers	2
Giants	Sunday	NULL	NULL
Dragons	Monday	Carp	NULL
Tigers	Monday	NULL	NULL
Carp	Monday	Dragons	NULL
Swallows	Monday	Giants	0
Bay Stars	Monday	NULL	NULL
Giants	Monday	Swallows	5

What is the result of the following query?

 SELECT S1.Team, S2.Team FROM Scores S1, Scores S2 WHERE S1.Opponent = S2.Opponent AND S1.Team <> S2.Team 

Identify in the list below a tuple of the result.

a)

Swallows

Swallows

b)

Giants

Giants

c)

Carp

Swallows

d)

Tigers

Tigers

8.

The latest scores from the Japanese Baseball League are in the table with schema

Scores(Team, Opponent, RunsFor, RunsAgainst)

The data in this table is as follows:

Team	Opponent	RunsFor	RunsAgainst
Dragons	Tigers	5	3
Carp	Swallows	4	6
Bay Stars	Giants	2	1
Marines	Hawks	5	3
Ham Fighters	Buffaloes	1	6
Lions	Golden Eagles	8	12
Tigers	Dragons	3	5
Swallows	Carp	6	4
Giants	Bay Stars	1	2
Hawks	Marines	3	5
Buffaloes	Ham Fighters	6	1
Golden Eagles	Lions	12	8

What is the result of executing on this data the query:

 SELECT Team FROM Scores WHERE RunsFor > RunsAgainst AND RunsFor <= RunsAgainst + 2 

Identify in the list below, the team that appears in the output.

		a)	Bay Stars
		b)	Ham Fighters
		c)	Carp
		d)	Giants

9.

Suppose relations R(A,B) and S(B,C,D) have the tuples shown below:

R =

A	B
1	2
3	4
5	6

S =

B	C	D
2	4	6
4	6	8
4	7	9

Compute the result of the join query:

 SELECT A, R.B, S.B, C, D FROM R, S WHERE R.A < S.C AND R.B < S.D 

Then, identify one of the tuples in the result from the list below.

		a)	(5,6,4,6,8)
		b)	(3,4,5,7,9)
		c)	(1,2,2,6,8)
		d)	(5,6,4,6,9)

10.

The latest scores from the Japanese Baseball League are in the table with schema

Scores(Team, Opponent, RunsFor, RunsAgainst)

The data in this table is as follows:

Team	Opponent	RunsFor	RunsAgainst
Dragons	Tigers	5	3
Carp	Swallows	4	6
Bay Stars	Giants	2	1
Marines	Hawks	5	3
Ham Fighters	Buffaloes	1	6
Lions	Golden Eagles	8	12
Tigers	Dragons	3	5
Swallows	Carp	6	4
Giants	Bay Stars	1	2
Hawks	Marines	3	5
Buffaloes	Ham Fighters	6	1
Golden Eagles	Lions	12	8

What is the result of executing on this data the query:

 SELECT S1.Team, S2.Team FROM Scores S1, Scores S2 WHERE S1.Team < S2.Team AND (S1.RunsFor = S2.RunsFor OR S1.RunsAgainst = S2.RunsAgainst) 

Remember that when strings are compared, "<" means "precedes in alphabetical order.

Identify, in the list below, a row of the result.

a)

Ham Fighters

Giants

b)

Tigers

Hawks

c)

Carp	Ham Fighters

d)

Buffaloes

Bay Stars