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Why foreign key column allowing null values even a parent
tables reference key column not having null value..
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Answer / rajkumar
Foreign key consider only the values. According to null value is not a value.
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Answer / sureshramsing@gmail.com
Yes foreign key column allows null values, if it is not having either primary key or not null constraints.
Foreign key just reference to the particular parent column only not for restrcting the data while insert or update. It verifies dependency at the time of delete only.
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