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databases Online Quiz - 236

Description: databases Online Quiz - 236
Number of Questions: 20
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Tags: databases
Attempted 0/20 Correct 0 Score 0
  1. Returns current date

  2. Generate the access plan

  3. Suggests performance hints that can be implemented

  4. Drop and create the stored procedure


Correct Option: D

The table rows and column are also known as?

  1. Attributes and Fields

  2. Fields and Records

  3. Records and Fields

  4. Fields and Attributes


Correct Option: C

Which of the following SQL functions can operate on any datatype?

  1. TO_CHAR

  2. TO_DATE

  3. MAX

  4. LPAD


Correct Option: C

AI Explanation

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

Option A) TO_CHAR - This function is used to convert a numeric or date expression to a character string. It cannot operate on any datatype, as it is specifically designed to convert numeric or date expressions.

Option B) TO_DATE - This function is used to convert a character string to a date value. It cannot operate on any datatype, as it is specifically designed to convert character strings to dates.

Option C) MAX - This function is used to return the maximum value from a set of values. It can operate on any datatype, including numeric, character, and date types. This makes it the correct answer to the question.

Option D) LPAD - This function is used to left pad a string with a specified character. It can operate on character strings only, and not on any other datatype.

The correct answer is Option C) MAX. This option is correct because the MAX function can operate on any datatype, whereas the other options are specific to certain datatypes.

Normalization is…?

  1. A special way of selecting data

  2. The process of adding primary key to a table

  3. The process of arranging information stored in a database in a way, which removes redundancy and ambiguity.

  4. A special way of retrieving data


Correct Option: C

AI Explanation

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

Option A) A special way of selecting data - This option is incorrect because normalization is not related to selecting data. Normalization is a process of organizing and structuring data in a database.

Option B) The process of adding a primary key to a table - This option is incorrect. While adding a primary key to a table is part of the database design process, it is not the definition of normalization. Normalization involves organizing data to eliminate redundancy and ensure data integrity.

Option C) The process of arranging information stored in a database in a way that removes redundancy and ambiguity - This option is correct. Normalization is the process of organizing data in a database to minimize redundancy and eliminate data anomalies, such as update, insert, and delete anomalies. It aims to improve data integrity and optimize database performance.

Option D) A special way of retrieving data - This option is incorrect. Normalization does not relate to retrieving data. It is focused on organizing and structuring data within a database.

The correct answer is C) The process of arranging information stored in a database in a way that removes redundancy and ambiguity. This option is correct because it accurately describes the concept of normalization.

which commands is combination of unions ?

  1. Rollup

  2. Rollback

  3. CUBE

  4. I and III both


Correct Option: D

On which data type indexes can not be created.

  1. NUMBER

  2. LONG

  3. VARCHAR2

  4. RAW


Correct Option: B
  1. NUMBER is the subtype of INTEGER data type

  2. PLS_INTEGER is the subtype of BINARY_INTEGER

  3. POSITIVE data type is defined in SYS package.

  4. None of the above.


Correct Option: B
  1. Only nested tables need initilization.

  2. Index-by tables is a persistent collection

  3. nested tables are known as associative arrays.

  4. VARRAYs hold fixed number of elements


Correct Option: D
  1. CURRVAL

  2. LEVEL

  3. ROWNUM

  4. COUNT


Correct Option: A,B,C

Choose the functions that can be used with NULL values

  1. NVL

  2. NULLIF

  3. DECODE

  4. COALESCE


Correct Option: A,B,D
  1. ALTER TABLE DROP COLUMN

  2. ALTER TABLE DROP CONSTRAINT

  3. ALTER TABLE DISABLE CONSTRAINT

  4. -


Correct Option: A

Choose the database objects

  1. TABLE

  2. VARCHAR2

  3. SEQUENCE

  4. INDEX


Correct Option: A,C,D

The file extension .xlt gets created when you save the file as

  1. an XML file

  2. a Web Page

  3. an excel template

  4. a text file


Correct Option: C

Which command will cause an automatic commit to occur?

  1. CONNECT

  2. RENAME

  3. INSERT

  4. DELETE


Correct Option: B
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