What's the difference between a primary key and a unique key?
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Answer Posted / srinivas
Primary key is a combination of unique+not null+cluster
index and it will not allow any duplicate values, null
values, and it's data will be arranged in ascending order
due to clustered index. Only one primary key is allowed
per table.
Unique key is a key which will not accept any duplicate
values, but it will accept one null value. We can place
any number of unique keys per table.
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