Hi Dear,
This article we will discuss what is the difference between primary key and
Foreign key. It is also a common interview question. Most of time at interview you will face this question.
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Primary key
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Foreign Key
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Primary key uniquely identify a record in the table
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Foreign key is a field in the table that is primary key in another table
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Primary Key can't accept null values
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Foreign key can accept multiple null values.
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We can have only one Primary key in a table.
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We can have more than one foreign key in a table
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