Database Management Systems Mid - II, April - 2015

1.A ___________ of a relation schema R consists of replacing the relation schema by two or more relation schemas that each contain a subset of the attributes of R and together includes all attributes in R.
  • Decomposition
  • Generalization
  • Normalization
  • specialization
Answer: A
2.A __________ is a Integrity Constraint that generalizes the concept of a key.
  • Normal forms
  • Functional Dependency
  • Primary Key
  • Foreign Key
Answer: B
3.Redundancy is dangerous as it is a potential threat to data ________
  • Integrity
  • consistency
  • sufficiency
  • both a) & b)
Answer: B
4._________ is either all the operations of the transaction are reflected properly in the database or none.
  • Durability
  • Consistency
  • Atomicity
  • Isolation
Answer: C
5.Once the changes caused by an aborted transaction have been undone, we say that transaction has been _______
  • Committed
  • Partially committed
  • Rolled back
  • Aborted
Answer: C
6.Validation protocols have the _______ phase
  • Read
  • Write
  • Validation
  • All of the above
Answer: D
7.The ____ rule requires only that the undo information in the log have been output to stable storage.
  • WAL
  • RAL
  • SAL
  • DAL
Answer: A
8.If a node is locked in an _____ mode, explicit locking is being done at a lower level.
  • intention-shared
  • shared lock
  • shared-intention
  • intention lock
Answer: D
9.The page allocation is ISAM contains _____________
  • Data Pages
  • Index[ages]
  • overflow pages
  • All of the above
Answer: D
10.Clustering indices are also called ___________
  • Primary indices
  • Secondary indices
  • dense indices
  • sparse indices
Answer: A
11.The set of all functional dependencies implied by a given set F of FD’s is called ________.
Answer: closure of F
12.The decomposition of the relation schema R with FD’s F into schemas with attribute sets X and Y is dependency preserving if ___________.
Answer: (FxU Fy)+ =F+.
13.The ________ scheme, which is based on making copies of the database.
Answer: Shadow copy
14.The number of transactions executed at a given amount of time is _________
Answer: Through put
15.A ____________ is one where for each pair of transactions Ti and Tj such that Tj reads a data item previously written by Ti, the commit operation of Ti appears before the commit operation of Tj
Answer: Recoverable Schedule
16.A ___________ can be implemented as a process that receives messages from transactions and messages in reply.
Answer: Lock Manager
17.Aries uses a ____ to identify log records.
Answer: Log Sequence Number
18.______index record appears for only some search key values
Answer: Sparse
19.The _____ of a balanced tree is the length of a path from root to leaf.
Answer: Height
20.ISAM stands for_______________________________.
Answer: Indexed Sequential Access Method