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Que. Consider the relation scheme R = {E, F, G, H, I, J, K, L, M, M} and the set of functional dependencies {{E, F} -> {G}, {F} -> {I, J}, {E, H} -> {K, L}, K -> {M}, L -> {N} on R. What is the key for R?
a. {E, F}
b. {E, F, H}
c. {E, F, H, K, L}
d. {E}
Answer:{E, F, H}
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Similar Questions:

Consider the following relational schema:

Suppliers(sid:integer, sname:string, city:string, street:string)
Parts(pid:integer, pname:string, color:string)
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Assume that, in the suppliers relation above, each supplier and each street within a city has a unique name, and (sname, city) forms a candidate key. No other functional dependencies are implied other than those implied by primary and candidate keys. Which one of the following is TRUE about the above schema?
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Select distinct STMP.supplierid
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Where STMP.supplierid = ITMP.supplierid
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For the warehouse at Nagpur, this query will find all suppliers who
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Given the following schema:

employees(emp-id, first-name, last-name, hire-date, dept-id, salary)
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You want to display the last names and hire dates of all latest hires in their respective departments in the location ID 1700. You issue the following query:

SQL> SELECT last-name, hire-date
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What is the outcome?
A relational database contains two tables student and department in which student table has columns roll_no, name and dept_id and department table has columns dept_id and dept_name. The following insert statements were executed successfully to populate the empty tables:

Insert into department values (1, 'Mathematics')
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Insert into student values (l, 'Navin', 1)
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Insert into student values (3, 'Gita', 1)

How many rows and columns will be retrieved by the following SQL statement?

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Let R (A, B, C, D, E, P, G) be a relational schema in which the following functional depen­dencies are known to hold: AB → CD, DE → P, C → E, P → C and B → G. The relational schema R is
The following table has two attributes A and C where A is the primary key and C is the foreign key referencing A with on-delete cascade.

A C
-----
2 4
3 4
4 3
5 2
7 2
9 5
6 4

The set of all tuples that must be additionally deleted to preserve referential integrity when the tuple (2,4) is deleted is:
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Data_of_Birth → Age
Age → Eligibility
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1. Registration_Num: Unique registration number
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3. BankAccount_Num: Unique account number at
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or join accounts. This attribute stores the
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