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Re: Problem with refering column from double nested subquery
Posted by: Ert ong
Date: September 22, 2013 11:59PM

Thanks your answer.

> the elements of a subquery are visible to the immediate outer query
Maybe I have not understood you correctly, but from INNER to OUTER behavior looks logical.

The problem is visibility from OUTER to INNER.

>> otherwise, many complex queries would be much harder to write.
If consider visibility from OUTER to INNER, IMHO we have the opposite.

If we do not propagate fields from OUTER to INNER query more than on one step, it becomes much more difficult to write queries with complex subqueries.

In any case we can put an alias to each table and easily distinguish fields from as many tables as we need. So name conflicts IMHO is not such a big issue, as impossibility to write complex subqueries.

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Re: Problem with refering column from double nested subquery
September 22, 2013 11:59PM


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