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databases Online Quiz - 238

Description: databases Online Quiz - 238
Number of Questions: 20
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Tags: databases
Attempted 0/20 Correct 0 Score 0

Each AMP is responsible for a subset of rows from each table.

  1. True

  2. False


Correct Option: A

It is impossible to have skewed data when employing a Non-Unique Primary Index value?

  1. True

  2. False


Correct Option: B

How does Teradata handle data distribution when performing system configuration changes

  1. Creates an output map to aid in redistributing data

  2. Data distribution is automatic

  3. Creates a reconfig map to help the DBA repartition data

  4. None of the above


Correct Option: B

Which of the following statements about hashing are true?

  1. The uniqueness value is a component of the row hash value.

  2. In a table that has a NUPI, all rows with the same NUPI value are distributed to the same AMP.

  3. Two Primary Index values that hash to the same row hash value are called hash synonyms.

  4. The output of the hashing algorithm is called the hash map


Correct Option: B,C

AI Explanation

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

Option A) The uniqueness value is a component of the row hash value - This option is incorrect. The uniqueness value is not a component of the row hash value. The row hash value is calculated based on the primary index value.

Option B) In a table that has a NUPI, all rows with the same NUPI value are distributed to the same AMP - This option is correct. In Teradata, when a table has a Non-Unique Primary Index (NUPI), all rows with the same NUPI value are distributed to the same Access Module Processor (AMP). This helps in efficient data retrieval and query processing.

Option C) Two Primary Index values that hash to the same row hash value are called hash synonyms - This option is correct. In Teradata, when two different primary index values hash to the same row hash value, they are referred to as hash synonyms. This can lead to data skew and imbalanced data distribution.

Option D) The output of the hashing algorithm is called the hash map - This option is incorrect. The output of the hashing algorithm is called the row hash value, not the hash map.

The correct answer is B, C. Option B is correct because it explains the behavior of NUPI in Teradata, and Option C is correct because it explains the concept of hash synonyms in Teradata.

What are the parts of PE?

  1. AMP's

  2. Parser

  3. Dispatcher

  4. Bynet

  5. Optimiser


Correct Option: B,C,E

Each AMP Corresponds to a particular Vdisk.

  1. True

  2. False


Correct Option: A
  1. Multiple

  2. One

  3. Two

  4. All of the above


Correct Option: B

Features of Primary Key are:

  1. Unique

  2. Non Unique

  3. Null

  4. Not Null

  5. All of the above


Correct Option: A,D

Which utilities can be used for both Export and Import?

  1. Fastload

  2. Multiload

  3. BTEQ

  4. TPump

  5. Teradata warehouse builder


Correct Option: B,C,E

Multiload can load data in populated tables.

  1. True

  2. False


Correct Option: A
  1. Can populate Single table

  2. Can load populated tables

  3. Tables with SI and referential integrity can be loaded

  4. Very fast if target table is empty

  5. Table loaded can be accesed while fastload runs.


Correct Option: A,D

A column of a table is declared as NUMBER(10,2).For which of the following values oracle returns an error during insertion

  1. 5392845.324

  2. 871039453.1

  3. 97234512.123

  4. 1234567.12


Correct Option: B

Error capturing is done by these utilities:

  1. BTEQ

  2. FASTLOAD

  3. MULTILOAD

  4. FASTEXPORT

  5. TPUMP


Correct Option: B,C,E

Sub query cannot have which clause defined for it

  1. having clause

  2. where clause

  3. order by clause

  4. group by clause


Correct Option: C

All DML's are supported by which utility?

  1. Mload

  2. Fload

  3. Bteq

  4. Tpump


Correct Option: C

Select length(-1) from dual What is the output of the above sql stmt

  1. 0

  2. 1

  3. 2

  4. error


Correct Option: C

If there are frequent updates in tables, then which utility to use?

  1. BTEQ

  2. TPUMP

  3. FASTEXPORT

  4. MULTILOAD


Correct Option: B
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