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To uniquely identify a record, as every primary key value must be unique.
To ensure every record has a key, as a primary key cannot be left blank.
To be used in creating relationships.
For sorting and searching records.
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∙ 14y ago
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Which field MS Access will not allow you to delete?
A primary key field.A primary key field.A primary key field.A primary key field.A primary key field.A primary key field.A primary key field.A primary key field.A primary key field.A primary key field.A primary key field.
How do you create an employee table with the uses of primary key?
CREATE TABLE EMPLOYEE (EMP_ID NUMBER(10) PRIMARY KEY,NAME VARCHAR2(100),EMAIL_ID VARCHAR2(50) UNIQUE);Hope it helped.SP.
Can super key be as primary key?
I think super key is treated as the primary key because in a table their will be only one primary key.
What are the importance of primary key?
Importance of primary key
What does the primary key in a data base do?
We know that primary key is the one that is not null and is always unique. A primary key uniquely identifies a record in a table.
What are the advantage of primary key?
Primary key that is used to identify a record uniquely. Primary key is a key that always unique and not null. A system generated primary key is called surrogate key.Primary key is the one which is always unique and not null. Advantage of primary key that it helps in identifying a tuple uniquely.
What is the primary key for the properties table?
Primary key is to set property ID as the primary key for the properties table.
How you create or assign primary key?
A primary key is never null and is also unique . Example of primary key is create table emp (ecode integer NOT NULL PRIMARY KEY);
How would you describe a condition in which one attribute is dependent on another attribute when neither attribute is part of the primary key?
Transitive Dependency
Why do you designate one of the candidate key of relation to be the primary key?
We designate one of the candidate key of a relation to be a primary key because that primary key is use for any foreign key references.
Candidate key and primary key differnece?
All Primary keys are definitely Candidate Keys. A Candidate key is one which can be used as a Primary key that is not null and unique. That is one of the candidate keys can be chosen as a primary key.A Candidate key is a Unique Key and it can be used to find out any particular Tuple (row) in a table. The following are the differences between A Candidate key and a Primary Key: 1) A Unique key can be null but not a Primary key 2) On a table we can have only 1 primary key but 'N' number of unique keys.
Can a primary key refer to a whole table?
No, a primary key do not refers to the whole table .A primary key refers to a field in the table that is not null and unique.
