Answer / sumit

Any number of Null values can be inserted in such a column.

Answer / amit

Any no. of times you can insert null values in a coulmn
whihc is unique constraint because a Null value is
undefined,unassigned,and unapplicable value so thats why we
cannot compaire with any other null value or other value.

Answer / ajay badola

Any number of null values can be inserted.

Answer / john bershan

any number of null value can be inserted into table for a
column which is declared as unique.coz null vale s either
not equal to any value or not equal to another null;

Answer / veerapandian muthupandi

Only one null

Answer / sheea pruthi

12

Answer / bhargav

single NULL

Answer / manish kumar

Single null Value
B'cse Unique Constraint contain unique value and single
null is also a unique value.

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