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Difference between primary key and unique key ?
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Answer Posted / dpkar
Primary Key:
Primary key will create column data uniqueness in the table.
Primary key will create clustered index by default
Only one Primay key can be created for a table
Multiple columns can be consolidated to form a single
primary key
It wont allow null values.
Unique Key :
Unique key constraint will provide you a constraint like
the column values should retain uniqueness.
It will allow null value in the column.
It will create non-clustered index by default
Any number of unique constraints can be added to a table.
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