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Recent questions tagged relational-calculus

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NIELIT 2017
If r is a relation in relational data model and a1,a2,..an are the attributes of relation r, what is the cardinality of r expressed in terms of domain of attributes?(a) |...
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NIELIT 2022 April Scientist B | Section B | Question: 83
Which of the following relational calculus expressions is not safe ?$\left\{t \mid \exists u \in R_1\left(t[A] = u[A]\right) \land \neg \exists s \in R_2 \left(t[A] = s[A...
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NIELIT Scientist B 2020 November: 111
An expression in the domain relational calculus is of the form:$\{ P(x_1,x_2,\dots ,x_n)|< x_1,x_2,\dots ,x_n \}$$\{ x_1,x_2,\dots ,x_n |< x_1,x_2,\dots ,x_n \}$$\{ x_1,...
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NIELIT 2016 MAR Scientist B - Section C: 42
The relational algebra expression equivalent to the tuple calculus expression$\{t\mid t ​ \in ​ r \land (t[A]=10 \land t[B]=20)\}$ is$\sigma_{(A=10\:\lor\:B=20)}(r)$$\sig...
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NIELIT 2017 July Scientist B (IT) - Section B: 19
If $R$ is a relation in Relational Data Model and $A_1,A_2,\dots A_n$ are the attributes of relation $R$, what is the cardinality of $R$ expressed in terms of domain of a...
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UGC NET CSE | June 2019 | Part 2 | Question: 31
Which of the following has same expressive power with regard to relational query language?Rational algebra and domain relational calculusRelational algebra and tuples rel...
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Raghuramkrishnan Exercise-4.3 question 11 page no-127 Relational Algebra
Suppliers(sid, sname, address)Parts(pid, pname, color)Catalog(sid, pid, cost)Find the pids of the most expensive parts supplied by suppliers named Yosemite Sham
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Raghuramkrishnan Exercise-4.3 page-127
Given relationcatalog(sid, pid, cost)Find pairs of sids such that the supplier with the first sid charges more for some part than the supplier with the second sidwhat is ...
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Raghuramkrishnan Exercise 4.1 Relational Algebra
Given two relations R1 and R2, where R1 contains N1 tuples, R2 contains N2 tuples, and N2>N1 0, give the minimum and maximum possible sizes (in tuples) for the result rel...
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ISI2017-PCB-CS-3-b
Consider the following relations:$\text{STD_CHOICES } (\underline{\text{Student_ID}}, \underline{\text{Course_ID}}, \text{Semester})$ and$\text{COURSE_ASSIGN} (\underline...
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DBMS Korth Edition 6 Exercise 6 Question 17 (Page No. 254)
Let R = (A, B) and S = (A, C), and let r (R) and s(S) be relations.Write SQL Queries equivalent to the following domain relational-calculus expressions:a. {< a | $\exist...
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DBMS Korth Edition 6 Exercise 6 Question 18 (Page No. 254)
Let R = (A, B) and S = (A, C), and let r (R) and s(S) be relations.Using the special constant null, write tuple-relational-calculus expressionsequivalent to each of the f...
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DBMS Korth Edition 6 Exercise 6 Question 19 (Page No. 254)
Give a tuple-relational-calculus expression to find the maximum value inrelation r (A).
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DBMS Korth Edition 6 Exercise 6 Question 15 (Page No. 253-254)
Consider the employee database shown here. Give expressions in tuplerelational calculus and domain relational calculus for each of the followingqueries:a. Find the names ...
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DBMS Korth Edition 6 Exercise 6 Question 8 (Page No. 251)
Consider the relational database given below where the primary keys areunderlined. Give an expression in tuple relational calculus for each of thefollowing queries:a. Fin...
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DBMS Korth Edition 6 Exercise 6 Question 7 (Page No. 251)
Let R = (A, B) and S = (A,C), and let r (R) and s(S) be relations.Writeexpressions in relational algebra for each of the following queries:a. {< a | ∃ b (< a, b ∈ r ∧ b...
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DBMS Korth Edition 6 Exercise 6 Question 6 (Page No. 251)
Let R = (A, B, C), and let r1 and r2 both be relations on schema R. Give an expression in the domain relational calculus that is equivalent to each of the following:a. $\...
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Relational algebra and SQL
SQL Aggregation is possible by extended relational algebra operators? SQL grouping is possible in relational algebra. Relational algebra is equivalent to safe relational ...
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UGC-NET CS 2016 question
Given i= 0, j = 1, k = – 1x = 0.5, y = 0.0What is the output of given ‘C’ expression ?x * 3 & & 3 || j | kexplanation please….
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RaghuramKrishnan
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?
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Zeal Workbook: Databases - Relational Calculus
Answer is all Doubt -how (1,4) is present in O/p
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Korth
give domain relation calculus expressionworks(person-name, company-name, salary)find the names of all employees who earn more than every employee of Small Bank Corporatio...
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Relational Algebra
Online Site For practicing Relational Algebrahttps://dbis-uibk.github.io/relax/calc.htm
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doubt
How we find the given calculus is safe or not
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Verifying Relational Algebra Question
I think it should be option a)All query $1,3,4$ are equivalent but $2$ is not equivalent.Query $2$ should be $\prod \text{Room no,hotel no,type,price}(\sigma \text{type='...
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Tuple Relational Calculus Query - Confirm the Answer
Relation Schema : Employee (Name, Ssn, Bdate, Address, Dept_number)Project (Pname, Pno, Dept_number)WorksOn (Essn, Pno, Hours)List the names of employees who work on all ...
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