A key which is used to identify the field or set in a database uniquely is called as a “ primary key ”. Hence, the answer is option “ D ”.

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Answer 1

Expert Solution & Answer

Chapter 5, Problem 1SAT

Program Description Answer

A key which is used to identify the field or set in a database uniquely is called as a “primary key”.

Hence, the answer is option “D”.

Expert Solution & Answer

Explanation of Solution

Primary key:

To identify each record in a table, at least there must be one data field which should be unique. That is, corresponding data field of every record should be unique. It is called a primary key.
Primary key is used to identify the unique record from a collection of records.
To relate two tables, a primary key field in one table is added to the related table, and it is called as a foreign key.

Explanation for incorrect options:

Attribute:

It is a property of an entity.
It has the information about the entity and this information is captured within the attribute.
For example, “name”, “address”, and “contact_number” are used to define the attribute about the customer.

Hence, the option “A” is wrong.

Data item:

Data item describes the particular object of the table.
The collection of data item in the same object may consider as row in a table.

Hence, the option “B” is wrong.

Record:

Record is an element which is present in the database.
The row of the table also known as record.

Hence, the option “C” is wrong.

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Answer 2

Expert Solution & Answer

Chapter 5, Problem 1SAT

Program Description Answer

A key which is used to identify the field or set in a database uniquely is called as a “primary key”.

Hence, the answer is option “D”.

Expert Solution & Answer

Explanation of Solution

Primary key:

To identify each record in a table, at least there must be one data field which should be unique. That is, corresponding data field of every record should be unique. It is called a primary key.
Primary key is used to identify the unique record from a collection of records.
To relate two tables, a primary key field in one table is added to the related table, and it is called as a foreign key.

Explanation for incorrect options:

Attribute:

It is a property of an entity.
It has the information about the entity and this information is captured within the attribute.
For example, “name”, “address”, and “contact_number” are used to define the attribute about the customer.

Hence, the option “A” is wrong.

Data item:

Data item describes the particular object of the table.
The collection of data item in the same object may consider as row in a table.

Hence, the option “B” is wrong.

Record:

Record is an element which is present in the database.
The row of the table also known as record.

Hence, the option “C” is wrong.

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Answer 3

Expert Solution & Answer

Chapter 5, Problem 1SAT

Program Description Answer

A key which is used to identify the field or set in a database uniquely is called as a “primary key”.

Hence, the answer is option “D”.

Expert Solution & Answer

Explanation of Solution

Primary key:

To identify each record in a table, at least there must be one data field which should be unique. That is, corresponding data field of every record should be unique. It is called a primary key.
Primary key is used to identify the unique record from a collection of records.
To relate two tables, a primary key field in one table is added to the related table, and it is called as a foreign key.

Explanation for incorrect options:

Attribute:

It is a property of an entity.
It has the information about the entity and this information is captured within the attribute.
For example, “name”, “address”, and “contact_number” are used to define the attribute about the customer.

Hence, the option “A” is wrong.

Data item:

Data item describes the particular object of the table.
The collection of data item in the same object may consider as row in a table.

Hence, the option “B” is wrong.

Record:

Record is an element which is present in the database.
The row of the table also known as record.

Hence, the option “C” is wrong.

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Answer 4

Expert Solution & Answer

Chapter 5, Problem 1SAT

Program Description Answer

A key which is used to identify the field or set in a database uniquely is called as a “primary key”.

Hence, the answer is option “D”.

Expert Solution & Answer

Explanation of Solution

Primary key:

To identify each record in a table, at least there must be one data field which should be unique. That is, corresponding data field of every record should be unique. It is called a primary key.
Primary key is used to identify the unique record from a collection of records.
To relate two tables, a primary key field in one table is added to the related table, and it is called as a foreign key.

Explanation for incorrect options:

Attribute:

It is a property of an entity.
It has the information about the entity and this information is captured within the attribute.
For example, “name”, “address”, and “contact_number” are used to define the attribute about the customer.

Hence, the option “A” is wrong.

Data item:

Data item describes the particular object of the table.
The collection of data item in the same object may consider as row in a table.

Hence, the option “B” is wrong.

Record:

Record is an element which is present in the database.
The row of the table also known as record.

Hence, the option “C” is wrong.

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Answer 5

Expert Solution & Answer

Answer 6

Expert Solution & Answer

Answer 7

Chapter 5, Problem 1SAT

Program Description Answer

A key which is used to identify the field or set in a database uniquely is called as a “primary key”.

Hence, the answer is option “D”.

Expert Solution & Answer

Explanation of Solution

Primary key:

To identify each record in a table, at least there must be one data field which should be unique. That is, corresponding data field of every record should be unique. It is called a primary key.
Primary key is used to identify the unique record from a collection of records.
To relate two tables, a primary key field in one table is added to the related table, and it is called as a foreign key.

Explanation for incorrect options:

Attribute:

It is a property of an entity.
It has the information about the entity and this information is captured within the attribute.
For example, “name”, “address”, and “contact_number” are used to define the attribute about the customer.

Hence, the option “A” is wrong.

Data item:

Data item describes the particular object of the table.
The collection of data item in the same object may consider as row in a table.

Hence, the option “B” is wrong.

Record:

Record is an element which is present in the database.
The row of the table also known as record.

Hence, the option “C” is wrong.

Answer 8

Chapter 5, Problem 1SAT

Program Description Answer

A key which is used to identify the field or set in a database uniquely is called as a “primary key”.

Hence, the answer is option “D”.

Expert Solution & Answer

Explanation of Solution

Primary key:

To identify each record in a table, at least there must be one data field which should be unique. That is, corresponding data field of every record should be unique. It is called a primary key.
Primary key is used to identify the unique record from a collection of records.
To relate two tables, a primary key field in one table is added to the related table, and it is called as a foreign key.

Explanation for incorrect options:

Attribute:

It is a property of an entity.
It has the information about the entity and this information is captured within the attribute.
For example, “name”, “address”, and “contact_number” are used to define the attribute about the customer.

Hence, the option “A” is wrong.

Data item:

Data item describes the particular object of the table.
The collection of data item in the same object may consider as row in a table.

Hence, the option “B” is wrong.

Record:

Record is an element which is present in the database.
The row of the table also known as record.

Hence, the option “C” is wrong.

Answer 9

Chapter 5, Problem 1SAT

Program Description Answer

A key which is used to identify the field or set in a database uniquely is called as a “primary key”.

Hence, the answer is option “D”.

Answer 10

Expert Solution & Answer

Explanation of Solution

Primary key:

To identify each record in a table, at least there must be one data field which should be unique. That is, corresponding data field of every record should be unique. It is called a primary key.
Primary key is used to identify the unique record from a collection of records.
To relate two tables, a primary key field in one table is added to the related table, and it is called as a foreign key.

Explanation for incorrect options:

Attribute:

It is a property of an entity.
It has the information about the entity and this information is captured within the attribute.
For example, “name”, “address”, and “contact_number” are used to define the attribute about the customer.

Hence, the option “A” is wrong.

Data item: