what is null value?
Answers were Sorted based on User's Feedback
Answer / ruchi singh
null is a value that is unknown , unavailable or
inapplicable. Null is not same as zero or blank space.
Is This Answer Correct ? | 48 Yes | 4 No |
Answer / pr@$@d
Null means unknown value
The value null can be regarded as an unknown value.
Therefore, the following select statement returns null:
select 5+7+null+9 from dual;
Note : A null can be assigned but it can not be equated
with anything: Even itself.
Regards,
-Pr@$@d.
prasadreddi@ymail.com
Is This Answer Correct ? | 18 Yes | 3 No |
1.It is undefined and uncomparable value.
2.It is not equal to 0 and SPACE.
3.It will not occupy any MEMORY.
4.It has to be supported by every RDBMS package to have
unique treatment for all data types.
5.Any arithematic operations with null returns a null value.
6.It represents with "NULL" keyword and display a space.
Is This Answer Correct ? | 10 Yes | 1 No |
Answer / purushotham
Null is an inapplicable or blank which is not equal to too.
null along with any operator results in NULL Except
concatenation.
Is This Answer Correct ? | 4 Yes | 1 No |
Answer / anilchauhan85
null value means null it it not equal 0 or space.
if we add,delete,subtract in null then return null.
ex.
1+2+null=null
Is This Answer Correct ? | 4 Yes | 3 No |
Answer / ela tiku
Null Value is neither zero nor it is a blank space. It is
some unknown value which occupies 4 bytes of space of
memory in SQL.
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / sridhark
NUll means 'UNknown' or 'Missing value' or 'Not known'
Is This Answer Correct ? | 0 Yes | 0 No |
Answer / kannan
Null value is unknown, unavailable .
NUll is not equal to Zero or Space .
Null is not equal to another Null value.
Null value can be assigned to variable or attributes (any
datatypes)
Is This Answer Correct ? | 0 Yes | 0 No |
Answer / ela
Null is not eqal to zero not is an empty space. it is
simply comprising of 4 bytes of unknown value.
Is This Answer Correct ? | 0 Yes | 0 No |
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