Relational Algebra - GATE PYQs | DBMS | With NOTES | Deepak Poonia

Q.35 Consider the following two relations, R(A,B) and S(A,C):
The total number of tuples obtained by evaluating the following expression
𝝈𝑩𝑪 (𝑹 ⋈𝑹.𝑨=𝑺.𝑨 𝑺) is

Consider a database that includes the following relations:
Defender(name)
Forward(name)
Team(name)
Which ONE of the following relational algebra expressions checks that every name occurring in Team appears in either Defender or Forward, where phi denotes the empty set?

Given the relations
employee, and
department (dept-no, dept-name,address),
Which of the following queries cannot be expressed using the basic relational algebra operations ?
Department address of every employee
Employees whose name is the same as their department name
The sum of all employees' salaries

Suppose and are two relation schemas. Let and be the corresponding relation instances.
is a foreign key that refers to in. If data in and satisfy referential integrity constraints, which of the following is ALWAYS TRUE?

In a relational database there are three relations: Which of the following relational algebra expressions returns the names of shops that have no customers at all? [Here
is the projection operator.]

In a relational database there are three relations: Relational Algebra expression for Customers who buy from all shops.

Consider the following three relations in a relational database. Which of the following relational algebra expressions return the set of eids who own all the brands?

SELECT operation in SQL is equivalent to
The selection operation in relational algebra
The projection operation in relational algebra, except that SELECT in SQL retains duplicates

Consider the following SQL query
Select distinct from where P
For an arbitrary predicate P, this query is equivalent to which of the following relational algebra expressions?

A table 'student' with schema (roll, name, hostel, marks), and another table 'hobby' with schema (roll, hobbyname) contains records as shown below: The following SQL query is executed on the above tables:
select hostel
from student natural join hobby
where marks = 75 and roll between 2000 and 3000;
A new relation is obtained by the following relational algebra operation: The difference between the number of rows output by the SQL statement and the number of tuples in is

Content of the video:
00:00:00 - GATE PYQs of Relational Algebra
00:00:16 - GATE CSE 2024 | Set 1 | Question: 25 - Number of tuples obtained by evaluating expression
00:09:56 - GATE DS&AI 2024 | Question: 16 - Relational Algebra Expressions, Team, Defender, Forward
00:34:42 - GATE CSE 2000 - Queries that cannot be expressed using the basic relational algebra operations
00:41:53 - GATE CSE 2012, 2004 - Foreign key, Referential integrity constraints
00:47:15 - TIFR CSE 2013 | Part B | Question: 19 - Relational database, Relational algebra expressions returns the names of shops that have no customers

00:59:44 - TIFR CSE 2010 | Part B | Question: 33 - Relational database, Relational algebra expression, Customers who buy from all shops
01:07:23 - GATE CSE 2022 | Question: 15 - Relational algebra expressions return the set of eids who own all the brands
01:31:59 - GATE CSE 2015 Set 1 | Question: 7 - SELECT operation in SQL is equivalent to projection operation in relational algebra
01:35:53 - GATE CSE 2003 | Question: 30 - SQL query equivalent relational algebra expressions
01:43:26 - GATE CSE 1997 | Question: 76-a - Relational algebra expression equivalent to SQL query

01:50:42 - GATE IT 2005 | Question: 68 - SQL, Relational algebra operation, difference between the number of rows

#gate2025 #goclasses #computerscience #gateda #gatecs #computer_science #gatecse

[SatyaDurgaPrasadMaddula]

01:48:30 : That SQL query definitely won't result in duplicate tuples, since both EMP and INVOLVED relations have primary keys. Am I correct?

[GOClassesforGATECS]

00:00:16 - GATE CSE 2024 | Set 1 | Question: 25 - Number of tuples obtained by evaluating expression
00:09:56 - GATE DS&AI 2024 | Question: 16 - Relational Algebra Expressions, Team, Defender, Forward
00:34:42 - GATE CSE 2000 - Queries that cannot be expressed using the basic relational algebra operations
00:41:53 - GATE CSE 2012, 2004 - Foreign key, Referential integrity constraints
00:47:15 - TIFR CSE 2013 | Part B | Question: 19 - Relational database, Relational algebra expressions returns the names of shops that have no customers

00:59:44 - TIFR CSE 2010 | Part B | Question: 33 - Relational database, Relational algebra expression, Customers who buy from all shops
01:07:23 - GATE CSE 2022 | Question: 15 - Relational algebra expressions return the set of eids who own all the brands
01:31:59 - GATE CSE 2015 Set 1 | Question: 7 - SELECT operation in SQL is equivalent to projection operation in relational algebra
01:35:53 - GATE CSE 2003 | Question: 30 - SQL query equivalent relational algebra expressions
01:43:26 - GATE CSE 1997 | Question: 76-a - Relational algebra expression equivalent to SQL query

01:50:42 - GATE IT 2005 | Question: 68 - SQL, Relational algebra operation, difference between the number of rows

[sarthaksuper]

Nice lectures sir! Done the whole playlist!

[Niketsinghcse]

A relation r(A, B) in a relational database has 1200 tuples. The attribute A has integer values ranging from 6 to 20, and the attribute B has integer values ranging from 1 to 20. Assume that the attributes A and B are independently distributed.

The estimated number of tuples in the output of sigma (A > 10) vee (B=18) (r) is

[sunstarstech]

sir i started dbms this play list is enough for gate or not... i am your full course go classes student... in class you coverd syllabus around 100+ hours... so if you teach us here within limited time... so that's why i ask playlist is enough or i need move forward to class ?!