Write the significance of a foreign key. -Technology

Write the significance of a foreign key. -Technology
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Answer :

A foreign key is used to Establish the relationship between any two tables of RDBMS.
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Related questions

What is the significance of a primary key? -Technology

Description : What is the significance of a primary key? -Technology

Last Answer : A primary key cannot allow null values and must have a unique index.

A foreign key is a reference of the ………….. key in another table. -Technology

Description : A foreign key is a reference of the ………….. key in another table. -Technology

Last Answer : A foreign key is a reference of the primary keyin another table.

A foreign key is a primary key in another table. -Technology

Description : A foreign key is a primary key in another table. -Technology

Last Answer : True When a table’s primary key field is added to a related table in order to create the common field which relates two tables, it is called a foreign key in the related table.

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What is the utility of primary key in database? Write distinct features of primary keys. -Technology

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Last Answer : The primary key is used to uniquely identify the record in a database. It can be a column or a set of columns in the table.Main features of the primary key are as follows:1. It must contain a unique value for each record of the table.2. It does not contain null values.

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Last Answer : Similarity: Column with both the constraints will only take unique values.Difference: Column with Primary key constraints will not be able to hold NULL values while Column with Unique constraints will be able to hold NULL values.

Write any one similarity and one difference between primary key and unique Constraint -Technology

Description : Write any one similarity and one difference between primary key and unique Constraint -Technology

Last Answer : Similarity: Column with both the constraints will only take unique values.Difference: Column with Primary key constraints will not be able to hold NULL values while Column with Unique constraints will be able to hold NULL values.

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Description : What is a primary key? -Technology

Last Answer : A field which uniquely identifies each record in a table is known as the primary key. e.g. emp id is the primary key of the Employee table.

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Description : Define primary key with an example. -Technology

Last Answer : A field which uniquely identifies each record in a table is known as the primary key. e.g. emp id is the primary key of the Employee table.

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Description : What is primary key? Give an example. -Technology

Last Answer : A field which uniquely identifies each record in a table is known as the primary key. e.g. emp id is the primary key of the Employee table.

What is a primary key in database? Give an example. -Technology

Description : What is a primary key in database? Give an example. -Technology

Last Answer : A field which uniquely identifies each record in a table is known as the primary key. e.g. emp id is the primary key of the Employee table.

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Description : Give one advantage of using primary key. -Technology

Last Answer : A primary key uniquely identifies the record in the table.

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Primary key is used to …………….. identify the record. -Technology

Description : Primary key is used to …………….. identify the record. -Technology

Last Answer : Primary key is used to uniquelyidentify the record.

The candidate key, which is not used as primary key is called ………….. key. -Technology

Description : The candidate key, which is not used as primary key is called ………….. key. -Technology

Last Answer : The candidate key, which is not used as primary key is calledalternate key.

Primary key field gives us permission to record duplicate entry. -Technology

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Last Answer : False A primary key is a key which identifies records uniquely in a table so it does not give us permission to record duplicate entry.

A primary key field does not allow numbers. -Technology

Description : A primary key field does not allow numbers. -Technology

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A primary key value can be NULL. -Technology

Description : A primary key value can be NULL. -Technology

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…………. is a field which is used as a primary key and numbers each record sequentially. -Technology

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Description : F4 key is used to start a Slide Show. -Technology

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Description : What is a primary key in a table? -Technology

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Description : What is a Foreign Key Field ?

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What are the Referential actions supported by FOREIGN KEY integrity constraint ?

Description : What are the Referential actions supported by FOREIGN KEY integrity constraint ?

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What are the Referential actions supported by FOREIGN KEY integrity constraint?

Description : What are the Referential actions supported by FOREIGN KEY integrity constraint?

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............. is a combination of two of more attributes used as a primary key A) Composite Key B) Alternate Key C) Candidate Key D) Foreign Key

Description : ............. is a combination of two of more attributes used as a primary key A) Composite Key B) Alternate Key C) Candidate Key D) Foreign Key

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The candidate key is that you choose to identify each row uniquely is called …………….. A) Alternet Key B) Primary Key C) Foreign Key D) None of the above

Description : The candidate key is that you choose to identify each row uniquely is called …………….. A) Alternet Key B) Primary Key C) Foreign Key D) None of the above

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ey to represent relationship between tables is called (A) Primary key (B) Secondary Key (C) Foreign Key (D) None of these

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Description : Which of the following statement is true? (1) A Primary key is also a candidate key (2) Each relation has at least one foreign key (3) Foreign keys can’t have null values (4) A Primary key is also an alternate key

Last Answer : Foreign keys can’t have null values

An attribute that uniquely identifies the rows of a table is known as the ....... key. (1) primary (2) candidate (3) composite (4) foreign

Description : An attribute that uniquely identifies the rows of a table is known as the ....... key. (1) primary (2) candidate (3) composite (4) foreign 

Last Answer : primary

Define the term Foreign Key.

Description : Define the term Foreign Key. 

Last Answer : A FOREIGN KEY is a key used to link two tables together. A FOREIGN KEY is a field (or collection of fields) in one table that refers to the PRIMARY KEY in another table. It ... between tables because it references the primary key of another table, thereby establishing a link between them.

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Have you ever accidentally activated the panic button on your vehicles key ring fob?

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Description : Write the significance of load factor?

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