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Greenhorn
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The book's answer to the statement "Identification variables can represent a single value or a collection" is false.
This is a bit confusing. The spec (11.2.7.2) says that "an identification variable never designates the collection in its entirety".
Indeed, an identification variable can represent a part of the collection
(using IN operator) which is still a collection, right?
 
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Hi Alex:

Originally posted by Alex Pakhomov:
The book's answer to the statement "Identification variables can represent a single value or a collection" is false.


What do you mean by this statement. Do you mean that it should have been checked? In my judgement, it should be unchecked because it is a false statement. According to the spec, an identification variable can't represent a collection just a member of a collection. You even quoted the appropriate section of the spec.

Originally posted by Alex Pakhomov:
The spec (11.2.7.2) says that "an identification variable never designates the collection in its entirety".


Does this help?
 
Alex Pakhomov
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Keith,
Thanks for the response. I was confused by "in its entiriety" piece.
That made me think that an identification variable used with IN operator
can represent something like a subset of collection.
It is clear from the context of its usage that an id variable represents a single entity, while IN statement defines its allowed range, more or less like a loop variable.
Thanks again.
- Alex
 
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