Tag: technology

Questions Related to technology

HttpConnection Interface in GCF MUST support which protocol?
technology embedded technologies

  1. HTTP 1.1

  2. HTTP 1.0

  3. HTTPS

  4. HTTP 2.0

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Correct Option: A

Every MIDlet MUST implement these three lifecycle methods.What are they?
technology embedded technologies

  1. initApp,pauseApp,destroyApp

  2. initApp,pauseApp,closeApp

  3. startApp,pauseApp,destroyApp

  4. startApp,pauseApp,stopApp

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Correct Option: C

Which software present in the mobile device controls the life cycle of the midlet?
technology embedded technologies

  1. Application Management Software

  2. Midlet Management Software

  3. Java Application Descriptor

  4. java Application Software

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Correct Option: A

In javaME, MSA stands for

technology embedded technologies

  1. Mobile Supplements Architecture

  2. Mobile Services Architecture

  3. Midlet Supplements Architecture

  4. Midlet Services Architecture

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Correct Option: B

What is the correct order to get a correct SQL statement?

technology databases

  1. SELECT FROM GROUP BY WHERE

  2. SELECT FROM GROUP BY ROLLUP

  3. SELECT GROUP BY FROM

  4. SELECT WHERE FROM GROUP BY

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Correct Option: B

NULL values violate CHECK constraint

technology databases

  1. True

  2. False

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Correct Option: B

Which of these operators is used to calculate super aggregate results?
technology databases

  1. ROLLUP

  2. COUNT

  3. AVG

  4. SUM

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Correct Option: A

Which is the syntax for enforcing the rule of deleting the dependent Foreign Key values on the deletion of a Primary Key?

technology databases

  1. ON DELETE SET NULL

  2. ON DELETE CASCADE

  3. ON DELETE DELETE

  4. ON DELETE RESTRICT

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Correct Option: B
Explanation:

To answer this question, the user needs to have knowledge of database management systems and the concept of Foreign Keys.

When a Foreign Key references a Primary Key in another table, there is a possibility that the referenced record(s) may be deleted. In such cases, four actions can be taken: SET NULL, CASCADE, DELETE, or RESTRICT.

  • ON DELETE SET NULL: This option sets the Foreign Key value to NULL when the referenced record(s) are deleted. This may lead to data integrity issues and is not ideal in most cases.

  • ON DELETE CASCADE: This option deletes all the dependent rows in the child table when the referenced rows in the parent table are deleted. This is usually the preferred option when the child rows are no longer relevant without the parent rows.

  • ON DELETE DELETE: This syntax does not exist, and hence, it is incorrect.

  • ON DELETE RESTRICT: This option prevents the deletion of the referenced rows in the parent table when there are dependent rows in the child table. This is useful when the data in the child table is still relevant and associated with the data in the parent table.

Therefore, the correct answer is:

The Answer is: B. ON DELETE CASCADE

UNION ALL has a comparitively faster performance compared to UNION?
technology databases

  1. True

  2. False

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Correct Option: A

Which of these is a String Aggregation function used to get values from different rows into a single column?
technology databases

  1. SUBSTR

  2. CON_STR

  3. CON_CAT

  4. WM_CONCAT

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Correct Option: D