Database [3i Infotech Placement]: Sample Questions 122 - 123 of 294

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Question 122

Database

Question

MCQ▾

Can we attach the same LOV to different fields at Design time?

Choices

Choice (4)

a.

No

b.

Yes

c.

Question does not provide sufficient data or is vague

d.

All of the above

Answer

b.

Explanation

  • Yes, we can attach the same LOV to different fields at DESIGN time.
  • In object navigator, double-click the object to display the property.
  • Set the LOV properties by entering the name of LOV.
  • Set display coordinate by the list X position and list Y position properties

Advantages of Separate LOV files:

  • Added to any page within an application.
  • All definitions are stored in one location, making it easy to locate and update.

Question 123

Database
Edit

Describe in Detail

Essay▾

What do you mean by Correlated subquery?

Explanation

  • A correlated subquery is a SQL query that depends on values executed by an outer query in order to complete.
  • Because a related subquery requires the outer query is executed first, the correlated subquery must run once for every row in the outer query.
  • This causes correlated subqueries to be less efficient than other subqueries.
  • Ex.

The objective is to find all employees whose salary is above average for their department.

SELECT employee_number, name

FROM employees AS emp

WHERE salary > (

SELECT AVG (salary)

FROM employees

WHERE department = emp. department) ;

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