Related Questions8 Items
Q1.MCQ
Consider two relations describing $teams$ and $players$ in a sports league:
- $teams(tid, tname)$: $tid, tname$ are team-id and team-name, respectively
- $players(pid, pname, tid)$: $pid, pname$, and $tid$ denote player-id, player-name and the team-id of the player, respectively
Which ONE of the following tuple relational calculus queries returns the name of the players who play for the team having $tname$ as $'MI'$?
Q2.M-MCQ
Consider a relational schema $team(name, city, owner)$, with functional dependencies $\{name \to city, name \to owner\}$.
The relation $team$ is decomposed into two relations, $t1(name, city)$ and $t2(name, owner)$. Which of the following statement(s) is/are TRUE?
Q3.MCQ
A schedule of three database transactions $T1$, $T2$, and $T3$ is shown. $Ri(A)$ and $Wi(A)$ denote read and write of data item $A$ by transaction $Ti, i = 1,2,3$. The transaction $T1$ aborts at the end. Which other transaction(s) will be required to be rolled back?
$$R1(X)\ W1(Y)\ R2(X)\ R2(Y)\ R3(Y)\ ABORT(T1)$$
Q4.NUMERICAL
Consider the following database tables of a sports league.
player(pid, pname, age)
team(tid, tname, city, cid)
coach(cid, cname)
members(pid, tid)
An instance of the table and an SQL query are given.
!image(https://uadmin.udsfgecw.tech/file/download/public/public:90929af6-06bc-450f-9e03-e6d904c2f68c.png)
sql
SELECT MIN(P.age)
FROM player P
WHERE P.pid IN (
SELECT M.pid
FROM team T, coach C, members M
WHERE C.cname = 'Mark'
AND T.cid = C.cid
AND M.tid = T.tid
)
Q5.M-MCQ
Consider the following $B^+$ tree with $5$ nodes, in which a node can store at most $3$ key values. The value $23$ is now inserted in the $B^+$ tree. Which of the following options(s) is/are CORRECT?
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Q6.NUMERICAL
Consider the following two relations, $R(A,B)$ and $S(A,C)$:
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The total number of tuples obtained by evaluating the following expression
$$\sigma{B < C}(R \bowtie{R.A = S.A} S)$$
is \\\\\\\\\\\
Q7.M-MCQ
The symbol $\rightarrow$ indicates functional dependency in the context of a relational database. Which of the following options is/are TRUE?
Q8.M-MCQ
Consider the following read-write schedule $S$ over three transactions $T1$, $T2$, and $T3$, where the subscripts in the schedule indicate transaction IDs:
$$S: r1(z); w1(z); r2(x); r3(y); w3(y); r2(y); w2(x); w2(y);$$
Which of the following transaction schedules is/are conflict equivalent to $S$ ?
Computer Science And EngineeringDatabase Management System (DBMS)Numerical Answer (NAT)1 Mark
Q6.
Consider the following two relations, R(A,B) and S(A,C):
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The total number of tuples obtained by evaluating the following expression σB<C(R⋈R.A=S.AS) is ___________
A
2