Can we use more than one null value for unique key?
- 31 Answers
- 59850 Views
- A1 Technology, Wipro, I also Faced
- E-Mail Answers
Answer Posted / talent pool
If we use more than one, it leads to
duplicate, which effects the fundamental property of unique
key.
But......
We can insert any number of null values in the column which
contains the unique key.
The reason is NULL is not equal to anothere NUll
so each null is different so there is no question of
duplication
| Is This Answer Correct ? | 57 Yes | 16 No |
Post New Answer View All Answers
Which column in the user.triggers data dictionary view shows that the trigger is a pl/sql trigger?
what are the other commands to know the structure of table using mysql commands except explain command? : Sql dba
Is pl sql different from sql?
how to create a new view in mysql? : Sql dba
What is java sql connection?
Is ms sql traffic encrypted?
differentiate between float and double. : Sql dba
How do I install sql?
What is a sql*loader control file?
How can we implement rollback or commit statement in a trigger?
What is database sql?
how many columns can be used for creating index? : Sql dba
What is microsoft t sql?
What is the maximum number of rows in sql table?
How to know the last executed procedure?
