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Question

Select operation in SQL is equivalent to

a.

the selection operation in relational algebra

b.

the selection operation in relational algebra, except that select in SQL retains duplicates

c.

the projection operation in relational algebra

d.

the projection operation in relational algebra, except that select in SQL retains duplicates

Answer: (d).the projection operation in relational algebra, except that select in SQL retains duplicates

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Q. Select operation in SQL is equivalent to

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