Recent questions tagged databases

1 votes
1 answer
1022
consider $r1(A,B,C),r2(C,D,E)$ and $r3(F,G)$ with primary key $A,C,F, r1$ has $150 ,r2$ has $100$ and $r3$ has $75$ tuples the number of tuples in $r1$ natural join $r2$ ...
3 votes
1 answer
1023
R(A, B, C, D)FD: B->C, D->Ais the following decomposition in BCNF?R1(B, C), R2(A, D), R3(C, D)
1 votes
1 answer
1025
What is coalescence rule in MVD?
1 votes
0 answers
1026
0 votes
0 answers
1028
Suppose the relationship S is one-to-one. Under which one of the following conditions, the one-to-one cardinality constraint is enforced on relation S?primary keysuper ke...
0 votes
1 answer
1030
relationparts(pid, pname, color)catalog(sid, pid, cost)find the sids of suppliers who supply every red part.can someone give the TRC and DRC expression for this?
0 votes
1 answer
1031
S=r1(A),w2(A),r3(A),w1(A),w3(A)Is this Schedule Non Recoverable? As there is a dirty read happening at w2(A)->r3(A)
0 votes
1 answer
1032
what is assertions in SQL?
0 votes
0 answers
1035
If I have dirty read which is write-read conflict does it imply that the schedule is non recoverable?Do all anomalies result of conflict result in non recoverable thereby...
1 votes
1 answer
1036
2 votes
2 answers
1038
what is the minimum and maximum number of keys for non-leaf nodes and leaf nodes for B+ Tree of order p?
0 votes
1 answer
1039
can anyone share some good resources fot B+ tree deletion?
0 votes
0 answers
1040
State True/False and explain the following statements. Recoverability implies no dirty read. Dirty read implies cascading rollbacks when transactions are more than $2$
0 votes
0 answers
1042
Consider the relation R(ABCDEFGHIJ) and the set of dependencies:F={AB->C, BD->EF, AD->GH, A->I, H->J}If we decompose R into 2NF and then to 3NF, the number of decomposed ...
2 votes
1 answer
1046
0 votes
1 answer
1047
1 votes
1 answer
1048
1 votes
1 answer
1049
3 votes
2 answers
1050
Tl:R(X), T1:R(Y), T1:W(X), T2:R(Y), T3:W(Y), Tl:W(X), T2:R(Y)is this schedule view serializable?