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How to write a subquery to implement the operation in the same way as if used the FORALL quantifier NOT? Jet SQL

I can not understand the essence of the task from uni :s

How to write a subquery to implement the operation in the same way as if used the FORALL quantifier NOT? Jet SQL

asked April 19th 20 at 12:13

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answered on

Solution

I think that this is a common Not IN. That is, for example, write:

In a nested select just list all the values you need many - this will be the quantifier FORALL. But taking the negation NOT IN - will be the negation of the quantifier FORALL and as a result of the implementation of the FORALL quantifier NOT.

`select * from table1 where some_id NOT IN (select some_id from table2 where some_conditon)`

In a nested select just list all the values you need many - this will be the quantifier FORALL. But taking the negation NOT IN - will be the negation of the quantifier FORALL and as a result of the implementation of the FORALL quantifier NOT.

Good evening, can you tell me is there some advantage before the FORALL IN (well, NOT option) ? Ie, I want to say that if there is IN, why would he "synonym" ? + If I understand correctly, FORALL is not fully standardized, but only for Oracle? - Lacy99 commented on April 19th 20 at 12:18

@Lacy99, good evening. Do not quite understand the question. The quantifier FORALL is the concept of predicate logic. - janice_Jones commented on April 19th 20 at 12:21

@janice_Jones, sorry. Not particularly familiar with the theory and thought it was just an additional operator in Jet SQL . Will be teaching a Mat. part) - Lacy99 commented on April 19th 20 at 12:24

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