The selection operator ($\sigma$) is used to filter tuples (rows) based on specified conditions.
Which relational algebra expression selects all employees from the emp table whose salary is greater than 40000 and who work in the Delhi location?
Asked in Analyst Cum Programmer (Deputy Director) 2024 · Topic: Basics of Computers and Information Technology (Database Management Systems (DBMS) Basics: Concepts, Types of Databases)
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Answer: A. $\sigma_{\text{salary>40000}} \wedge \text{location='Delhi'}(emp)$
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