What are the Limitations of a CHECK Constraint ?
Answers were Sorted based on User's Feedback
Answer / priyanka
conditions mentioned in the CHECK constraint must be a
boolean exp,they cannot be subqueries or sequences n
cannot include the SYSDATE,UID,USER, USERNV SQLfunctions
Is This Answer Correct ? | 13 Yes | 2 No |
Answer / pkd
with check constraint, you can not use pseudo column
(sysdate) function
Is This Answer Correct ? | 11 Yes | 3 No |
Answer / surya
It is used to avoid invalid and inconsistence data into the
data base table.
For example if you specify like this
sal int Check(sal>=1000)
and trying to insert value below 1000 in the sal
column,they won't accept you.That means it restrict the
data in the database table.
Is This Answer Correct ? | 8 Yes | 4 No |
Answer / vijay kumar jakkam
1. A CHECK constraint evaluates to TRUE when the resulting value of the CHECK constraint expression is unknown, e.g. when the expression contains NULL.
Example: A CHECK constraint that enforces the value of a particular column to be >0 evaluates to TRUE if NULL passed while inserting.
2. CHECK Constraints are not evaluated for delete statements.
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / ratnarao
The check consttraint should be with in the two boundaries
(min value to max value).
Is This Answer Correct ? | 5 Yes | 9 No |
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