Q. Consider the following three SQL queries (Assume the data in the people table) :

(a) Select Name from people where Age>21;
(b) Select Name from people where Height>180;
(c) Select Name from people where (Age>21) or (Height>180);

If the SQL queries (a) and (b) above, return 10 rows and 7 rows in the result set respectively, then what is one possible number of rows returned by the SQL query (c) ?

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Q. Manager's salary details are hidden from the employee. This is called as

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Q. Which of the following statements is false ?

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Q. A clustering index is created when ................

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Q. Let R ={A, B, C, D, E, F} be a relation schema with the following dependencies C→F,E→A,EC→D,A→B
Which of the following is a key for R ?

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Q. Match the following:

List-I                                          List-II
a. DDL                                        i. LOCK TABLE
b. DML                                       ii. COMMIT
c. TCL                                        iii. Natural Difference
d. BINARY Operation             iv. REVOKE

​Codes:
      a    b    c    d

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Q. The student marks should not be greater than 100. This is

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Q. Usage of Preemption and Transaction Rollback prevents ..................

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Q. Views are useful for ................. unwanted information, and for collecting together information from more than one relation into a single view.

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Q. Cross_tab displays permit users to view ................ of multidimensional data at a time.

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Q. Thoma’s-write rule is .................

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Q. .................. constraints ensure that a value that appears in one relation for a given set of attributes also appears for a certain set of attributes in another relation.

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Q. 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

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Q. 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 Rs 12,000 ?

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Q. 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)

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Q. Which of the following is not a type of Database Management System?

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Q. Manager's salary details are to be hidden from Employee Table. This Technique is called as

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Q. A Network Schema

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Q. Which normal form is considered as adequate for usual database design?

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Q. If D1, D2,…. Dn are domains in a relational model, then the relation is a table, which is a subset of

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