Let us now talk about the relational operations:

SELECT

The select operation is used to select few specific record from the database based on different criteria, This is a unary operation mathematically denoted as σ

Syntax:

σ  (Relation)

The Boolean expression is specified in is made of a number of clauses of the form:

or

Comparison operators in the set { ≤, ≥, ≠, =, <, <} apply to the attributes whose domains are ordered value like as integer.

---

Related Discussions:- Relational operations

boyce codd normal form relations, Create centralized relational database u... Create centralized relational database using bottom up method.   (a) Recognize a single un-normalized relation for the above scenario.          (b) Recognize the primary key for

What is interaction diagram, What is Interaction Diagram An interactio... What is Interaction Diagram An interaction diagram shows an interaction, comprises of a set of objects and their relationships including the messages that may be dispatched be

What does authentication refer, What does authentication refer? Authent... What does authentication refer? Authentication refers to the task of verifying the uniqueness of a person.

What is a database, What is a Database? To know what database is, we ha... What is a Database? To know what database is, we have to start from data, which is the basic building block of any DBMS. Data: Facts, figures, statistics etc. having no pa

ANSI SPARC architecture, explain ANSI SPARC architecture explain ANSI SPARC architecture

BOGUS VS GENUINE EMPOWERMENT, what is bogus empowerment. And what is genuin... what is bogus empowerment. And what is genuine empowerment

What is the use of with clause in sql, What is the use of with clause in SQ... What is the use of with clause in SQL? The with clause gives a way of defining a temporary view whose explanation is available only to the query in which the with clause occurs

BCA, Ask qu. Write a XML with database with book details (Book ID, Title, A... Ask qu. Write a XML with database with book details (Book ID, Title, Author, subject, published year, language, vendor, and price).estion #Minimum 100 words accepted#

What is a disjoint less constraint, What is a disjoint less constraint? ... What is a disjoint less constraint? Ans: It needs that an entity belongs to no much more than one level entity set.  Disjoint less constraint needs that an entity belongs to

Operator precedence-data manipulation language, Operator Precedence The... Operator Precedence The basic operators used in SQL are * /   - + Operators of the similar priority are evaluated From Left to right Parentheses are used to force priorit

Write Your Message!

Name