Consider a relation geq which represents “greater than or equal to”, that is, (x,y) ∈ geq only if y >= x.
create table geq
(
ib integer not null
ub integer not null
primary key 1b
foreign key (ub) references geq on delete cascade
)
Which of the following is possible if a tuple (x,y) is deleted?
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A
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A tuple (z,w) with z > y is deleted
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B
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A tuple (z,w) with z > x is deleted
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C
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A tuple (z,w) with w < x is deleted
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D
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The deletion of (x,y) is prohibited
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