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Database: How many primary key constraints can be created for one table?

Posted By :shankey     Posted Date :August 01, 2011    Points :40   Category :Sql Server 
Only one primary key constraints can be created for one table.

You can also find related Interview Question to Database: How many primary key constraints can be created for one table?  below: 

Which option is used to drop constraints specified on the table?

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how to find the table name in sql server database?

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How do we get primary key information in oracle table?

we can get primary key information with the following SQL statement

SELECT b.table_name, b.column_name, b.position, a.status, cons.owner
FROM all_constraints a, all_cons_columns b
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AND a.constraint_name = b.constraint_name
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Difference between primary and unique key constraints

Unique Key Constraints
The column values should retain uniqueness.
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It will not allow Null values.
By default Primary key will create clustered index.
Only one Primary key can be created for a table.

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Can indexes be created on more than one column of a table?

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