Tag: databases

Questions Related to databases

MAXVALUE is a valid parameter for sequence creation.
technology databases

  1. True

  2. False

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Correct Option: A

Dropping a table has which of the following effects on a nonunique index created for the table?

technology databases

  1. No effect

  2. The index will be rendered invalid

  3. The index will be dropped

  4. The index will contain NULL values.

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Correct Option: C

AI Explanation

To answer this question, we need to understand what happens to a nonunique index when a table is dropped.

Option A) No effect - This option is incorrect because dropping a table does have an effect on the index.

Option B) The index will be rendered invalid - This option is incorrect. When a table is dropped, the index is not rendered invalid. It is either dropped or remains intact.

Option C) The index will be dropped - This option is correct. When a table is dropped, all associated indexes are also dropped. This includes nonunique indexes created for the table.

Option D) The index will contain NULL values - This option is incorrect. Dropping a table does not affect the existing values in the index. Instead, the index itself is either dropped or remains intact.

The correct answer is C) The index will be dropped. This option is correct because when a table is dropped, all associated indexes, including nonunique indexes, are also dropped.

Which of the following is not a group function?
technology databases

  1. avg()

  2. sqrt()

  3. max()

  4. sum()

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Correct Option: B

You query the database with this command SELECT name FROM employee WHERE name LIKE ‘_a%’; Which names are displayed?
technology databases

  1. Names starting with “a”

  2. Names with "a" as second character

  3. Last character as "a"

  4. Names with atleast two "a" at the start.

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Correct Option: B

Which SQL keyword is used to specify conditional search?
technology databases

  1. SELECT

  2. WHERE

  3. SEARCH

  4. FIND

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Correct Option: B

The HAVING clause can be used only with
technology databases

  1. DELETE clause

  2. INSERT clause

  3. SELECT clause

  4. JOIN clause

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Correct Option: C

What does SQL stand for?
technology databases

  1. Strong Query Language

  2. Standard Query Language

  3. Strict Query Language

  4. Structured Query Language

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Correct Option: D

What does follow after the SQL WHERE clause?
technology databases

  1. The name of the table we are selecting from

  2. list of columns to be selected

  3. Definition of the condition to be met for the rows to be returned

  4. None of above

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Correct Option: C

What is a primary key?

technology databases

  1. The primary key column is a column or combination of columns whose values can be non-unique

  2. The primary key is a column or combination of columns whose values uniquely identify each row in the table

  3. The primary key is a column that can have NULL values

  4. all of above

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Correct Option: B

What is an index?
technology databases

  1. An index is the same as alias

  2. An index is a database table attribute, which speeds-up data search within a table

  3. An index is a special way to join 2 or more tables

  4. None of above

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Correct Option: B