Difference between primary key and unique key ?
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Answer Posted / omkar
In any table there can be one and only one primary key
(composite priamry key can have more than 1 column but
together conside one key only) but more than one unique
keys.
Primary key cannot accecpt null value.unique key accecpts
one or more than one null values.
primary key uniquly identifies the table but unique key is
used for uniquly identified of table as it contain one or
more than onee null.
Clustered index is created on
Primary key constraint and non clustered unique indexes is
created on Unique key constraint.
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