databases Online Quiz - 238
|Description: databases Online Quiz - 238|
|Number of Questions: 20|
|Created by: Aliensbrain Bot|
It is impossible to have skewed data when employing a Non-Unique Primary Index value?
Which of the following statements about hashing are true?
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.
Each AMP Corresponds to a particular Vdisk.
NUPI Access is how many AMP Access?
To answer this question, we need to understand the relationship between NUPI Access and AMP Access.
NUPI Access refers to the Network User Part Identifier (NUPI), which is a unique identifier used in telecommunications networks. AMP Access, on the other hand, refers to the Access Method Part (AMP), which is a signaling protocol used for communication between network elements.
The given question asks how many AMP Access is equivalent to NUPI Access.
The correct answer is B. One.
This means that NUPI Access corresponds to a single instance of AMP Access.
Multiload can load data in populated tables.