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LangRef 2.5beta1 - a few suggestions /2b

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LangRef 2.5beta1 - a few suggestions /2b

Aage Johansen

A few more:

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  p.53   (top)
[ ] ( ) | ^ - + * % _ ? {


No "}" (terminating brace) ?


[:ALPHA:]: Latin letters a..z and A..z.
Should be:  a..z and A..Z ?



----------------------------------------

p.57   Existential Predicates
... Existential predicates are so called because they use various
methods to test the existence of the value on the left side of the
predicate in the output results of subqueries on the right.

Using the first example:
   SELECT *
   FROM employee
   WHERE EXISTS(SELECT *
                FROM employee_project ep
                WHERE ep.emp_no = employee.emp_no)

What is the "value on the left side of the predicate" and what is
"output result of subqueries on the right"?
It is not intuitive to me.

It seems to be better explained in the next paragraph, but the end is
not very clear:
... tests the fact of the existence of any number of matching rows
that is greater than none.

Would something like
... tests the existence of at least one matching row.
be simpler and clearer?

----------------------------------------

--
Aage J.


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