it's a way of proving that the sql can't be correct.

if you have a very simple data basis and a (short) sequence of sql
keywords, it should be easy to give an expected result if the sequence
of sql keywords forms a valid select statement. If you can't determine
an expected result, the sequence of keywords is very unlikely to be a
valid statement.

If someone turns up with an expected result, although the sequence of
keywords isn't a valid statement, you get a clue about how that person
misinterprets the keywords. It will be easier then to explain where he
or she is thinking wrongly.

Asking for the expected result is something I regularly use in SQL
classes and it proves to be a strong method. A student is forced to
think about the meaning of the "statement" and (after a "why?") forced
to explain his/her interpretation of SQL keywords.

Ronald


--
rjeninga

Ingres Forums wrote:
I can see how that might work for a classroom situation - I'm not sure
your intention came across well in a newsgroup though (well it didn't
for me).

http://www.theregister.co.uk/2009/07...datawarehouse/

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