Which is the symbol used to denote the SELECT operation?

Related MCQs

• Which of the following is used to denote the selection operation in relational algebra?
• View the Exhibit and examine the data in the EMPLOYEES tables. Evaluate the following SQL statement: SELECT employee_id, department_id FROM employees WHERE department_id= 50 ORDER BY department_id UNION SELECT employee_id, department_id FROM employees WHERE department_id= 90 UNION SELECT employee_id, department_id FROM employees WHERE department_id= 10; What would be the outcome of the above SQL statement?
• Once the lower-level lock is released, the operation cannot be undone by using the old values of updated data items, and must instead be undone by executing a compensating operation; such an operation is called
• View the Exhibit and examine the structure of the EMPLOYEES and DEPARTMENTS tables. Which SET operator would you use in the blank space in the following SQL statement to list the departments where all the employees have managers? SELECT department_id FROM departments ____ SELECT department_id FROM employees WHERE manager_id IS NULL;
• Which of the following is the clause that makes a singleton SELECT different from the normal SELECT?
• For which Exception, if a SELECT statement attempts to retrieve data based on its conditions, this exception is raised when no rows satisfy the SELECT criteria?
• The operation which is not considered a basic operation of relational algebra is
• For select operation the                  appear in the subscript and the                         argument appears in the paranthesis after the sigma.
• For select operation the ________ appear in the subscript and the ___________ argument appears in the paranthesis after the sigmA:)
• Whenever an update operation occurs on a page, the operation stores the LSN of its log record in the                field of the page.