Tag: technology

Questions Related to technology

Can Composite Key be Null?

technology databases

  1. True

  2. False

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Correct Option: B

OBject Relational Database have entity relations?

technology databases

  1. True

  2. False

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Correct Option: B

Is DB2 database managament system?
technology databases

  1. True

  2. False

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Correct Option: A

Which SQL keyword is used to sort the result-set?
technology databases

  1. SORT BY

  2. SORT

  3. ORDER

  4. ORDER BY

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Correct Option: D

How can you change "Hansen" into "Nilsen" in the "LastName" column in the Persons table?
technology databases

  1. MODIFY Persons SET LastName='Nilsen' WHERE LastName='Hansen'

  2. MODIFY Persons SET LastName='Hansen' INTO LastName='Nilsen

  3. UPDATE Persons SET LastName='Hansen' INTO LastName='Nilsen'

  4. UPDATE Persons SET LastName='Nilsen' WHERE LastName='Hansen'

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Correct Option: D

With SQL, how can you return the number of records in the "Persons" table?
technology databases

  1. SELECT COUNT(*) FROM Persons

  2. SELECT COLUMNS(*) FROM Persons

  3. SELECT COLUMNS() FROM Persons

  4. SELECT COUNT() FROM Persons

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Correct Option: A

With SQL, how do you select all the records from a table named "Persons" where the value of the column "FirstName" is "Peter"?
technology databases

  1. SELECT [all] FROM Persons WHERE FirstName LIKE 'Peter'

  2. SELECT * FROM Persons WHERE FirstName<>'Peter'

  3. SELECT [all] FROM Persons WHERE FirstName='Peter'

  4. SELECT * FROM Persons WHERE FirstName='Peter'

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Correct Option: D

With SQL, how do you select all the records from a table named "Persons" where the value of the column "FirstName" starts with an "a"?
technology databases

  1. SELECT * FROM Persons WHERE FirstName LIKE '%a'

  2. SELECT * FROM Persons WHERE FirstName='%a%'

  3. SELECT * FROM Persons WHERE FirstName='a'

  4. SELECT * FROM Persons WHERE FirstName LIKE 'a%'

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Correct Option: D

The OR operator displays a record if ANY conditions listed are true. The AND operator displays a record if ALL of the conditions listed are true

technology databases

  1. True

  2. False

Show answer
Correct Option: B

AI Explanation

To answer this question, let's go through each option to understand why it is correct or incorrect:

Option A) True - This option is incorrect because the OR operator displays a record if at least one of the conditions listed is true, not any condition.

Option B) False - This option is correct because the AND operator displays a record only if all of the conditions listed are true.

The correct answer is B) False. This option is correct because the statement correctly explains the behavior of the AND operator, but not the OR operator. The OR operator displays a record if at least one of the conditions listed is true, not any condition.

With SQL, how can you return all the records from a table named "Persons" sorted descending by "FirstName"?

technology databases

  1. SELECT * FROM Persons SORT BY 'FirstName' DESC

  2. SELECT * FROM Persons SORT 'FirstName' DESC

  3. SELECT * FROM Persons ORDER BY FirstName DESC

  4. SELECT * FROM Persons ORDER FirstName DESC

Show answer
Correct Option: C

AI Explanation

To return all the records from a table named "Persons" sorted descending by "FirstName" in SQL, you can use the "ORDER BY" clause.

Let's go through each option to understand why it is correct or incorrect:

Option A) SELECT * FROM Persons SORT BY 'FirstName' DESC - This option is incorrect because the correct keyword to sort in SQL is "ORDER BY" and not "SORT BY".

Option B) SELECT * FROM Persons SORT 'FirstName' DESC - This option is incorrect because the correct keyword to sort in SQL is "ORDER BY" and not "SORT". Additionally, the syntax for specifying the column to sort by should not be enclosed in single quotes ('FirstName').

Option C) SELECT * FROM Persons ORDER BY FirstName DESC - This option is correct. It uses the "ORDER BY" clause to sort the records in descending order based on the "FirstName" column.

Option D) SELECT * FROM Persons ORDER FirstName DESC - This option is incorrect because the correct syntax to specify the column to sort by is "ORDER BY" followed by the column name. Here, the "FirstName" column is missing the "BY" keyword.

The correct answer is C. This option is correct because it uses the "ORDER BY" clause with the correct syntax to sort the records in descending order by the "FirstName" column.