Explain the key constraints and constraints on Null Values
with examples?
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Answer / amit
hi ,
key constraits i.e. referential integerity means
all values in foreign key must be in primary key , but it
may happnes that NULL values may be in foreign key , but
not in primary key .
this is done to cater some of the exception conditions.
| Is This Answer Correct ? | 4 Yes | 1 No |
Answer / navin kumar
because the key constraints can contains NULL value
but constrains not.
navin south delhi
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