CS352 Comprehensive Exam Model Questions
Usage of Preemption and Transaction Rollback prevents ______. *
1 point
Data manipulation
Views are useful for _____ unwanted information, and for collecting together information from more than one relation into a single view. *
1 point
Hiding
The decision tree classifier is a widely used technique for ______. *
1 point
Classification
Other:
Cross_tab displays permit users to view ______ of multidimensional data at a time. *
1 point
1 − dimension
Other:
Thoma’s-write rule is ______. *
1 point
Two phase locking protocol
Other:
Value that appears in one relation for a given set of attributes also appears for a certain set of attributes in another relation. *
1 point
Logical Integrity
Other:
The SQL expression Select distinct T, branch_name from branch T, branch S where T.assets ‹ S.assets and S.branch_city= “Mumbai” finds the names of *
1 point
All branches that have greater assets than some branch located in Mumbai.
Other:
Consider the following schemas : Branch_Schema = (branch_name, assets, city) Customer_Schema = (cutstomer_name, street, city) Deposit_Schema = (branch_name, account_number, customer_name, balance) Borrow_Schema = (branch_name, loan_number, customer_name, amount) Which of the following tuple relational calculus finds all customers who have loan amount more than ` 12,000 ? *
1 point
t(customer_name) | t∈borrow[?] t[amount]›12000}
Other:
Match the following : (a) Create (i) The E-R Model (b) Select (ii) Relationship Model (c) Rectangle (iii) DDL (d) Record (iv) DML Codes : (a) (b) (c) (d) *
1 point
(iii) (iv) (i) (ii)
Other:
Which of the following is true ? *
1 point
A relation in BCNF is always in 3NF
Other:
The User Work Area (UWA) is a set of Program variables declared in the host program to communicate the contents of individual records between *
1 point
DBMS & the Host record
Other:
If a relation with a Schema R is decomposed into two relations R1 and R2 such that (R1 ∪ R2) = R1 then which one of the following is to be satisfied for a lossless joint decomposition (→ indicates functional dependency) *
1 point
(R1 ∩ R2) → R1 or R1 ∩ R2 → R2
Other:
Which level of Abstraction describes how data are stored in the data base ? *
1 point
Physical level
Other:
Third normal form is based on the concept of ______. *
1 point
Closure Dependency
Other:
Referential integrity is directly related to *
1 point
Relation key
Other:
In multiuser database if two users wish to update the same record at the same time, they are prevented from doing so by *
1 point
Jamming
Other:
B+ tree are preferred to binary tree in Database because *
1 point
Disk capacity are greater than memory capacities
Other:
A Transaction Manager is which of the following ? *
1 point
Maintains a log of transactions
Other:
What is Granularity ? *
1 point
The size of database
Other:
Which level of Abstraction describes what data are stored in the Database ? *
1 point
Physical level
Other:
The problem that occurs when one transaction updates a database item and then the transaction fails for some reason is ________. *
0 points
Temporary Select Problem
Other:
Consider a schema R(A, B, C, D) and functional dependencies A → B and C → D. Then the decomposition R1(A, B) and R2(C, D) is *
1 point
Dependency preserving but not lossless join
Other:
If D1,D2, ....Dn are domains in a relational model, then the relation is a table, which is a subset of *
1 point
D1+D2+... +Dn
Other:
Which of the following is not a type of Database Management System ? *
1 point
Hierarchical
Other:
Manager&rsquos salary details are to be hidden from Employee Table. This Technique is called as *
1 point
Conceptual level Datahiding
Other:
A Network Schema *
1 point
restricts to one to many relationship
Other:
The relation “divides” on a set of positive integers is ________. *
1 point
Symmetric and transitive
Other:
The “PROJECT” operator of a relational algebra creates a new table that has always *
1 point
More columns than columns in original table
Other:
The employee information of an Organization is stored in the relation : Employee (name, sex, salary, deptname) Consider the following SQL query Select deptname from Employee Where sex = ‘M’ group by deptname having avg (salary) > {select avg (salary) from Employee} Output of the given query corresponds to *
1 point
Average salary of employee more than average salary of the organization.
Other:
For a database relation R(a, b, c, d) where the domains of a, b, c, d include only the atomic values. The functional dependency a → c, b → d holds in the following relation *
1 point
In 1NF not in 2NF
Other:
Match the following : a.Foreign keys i.Domain constraint b.Private key ii.Referential integrity c.Event control action model iii.Encryption d.Data security iv. Trigger *
1 point
a b c d iii ii i iv
Other:
SQL command to delete a column from an existing table: *
1 point
Alter table
Other:
With QBE, inserting records from one or more source tables into a single target table can be achieved by: *
1 point
Append action query
Other:
Tuple in relational algebra refers to: *
1 point
Row
Other:
An attribute or set of attributes within one relation that matches the candidate key of some(possibly the same) relation: *
1 point
Super Key
Other:
A subset of data in a data warehouse in the form of summary data, related to a particular department or business function: *
1 point
Meta Data
Other:
The normalization of 1NF relations to 2NF involves: *
1 point
Removal of partial dependencies
Other:
Why do we go for Normalization of Data Bases? *
1 point
To avoid the repetitions
Other:
if a relation is in BCNF then it is in: *
1 point
2 NF
Other:
A file is: *
1 point
an abstract data type
Other:
What property of the files prevents sharing of files and directories? *
1 point
Tree structure
Other:
E-R modeling technique is: *
1 point
Tree structure
Other:
Data items stored as grouped items is: *
1 point
Record
Other:
Data items are fragmented, replicated and propagated in: *
1 point
DBMS
Other:
If every non-key attribute is functionally dependent on the primary key, then the relation will be in *
1 point
1NF
Other:
which of the following is record based logical model(s)? *
1 point
Network Model
Other:
In an E-R diagram ellipses represents *
1 point
Entity sets
Other:
The set of permitted values for each attribute is called its *
1 point
Attribute set