Postmaster getting veeeery big: SUBSTR bug

Never mind my initial query, it was just used for demonstration purposes.
Herouth was right in stating: "memory used for substr function" has to be
the real cause of the problem because any substr select exhibits this
behaviour:

select substr(tets,1,2) from raw_field;

This one starts the postmaster at around 3MB and finishes at 40.
Unfortunately, I have no idea about C, can someone identify the problem
and come up with a patch?

greetings

Eildert Groeneveld
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Institute for
Animal Science and Animal Behaviour
Mariensee 31535 Neustadt Germany
Tel : (49)(0)5034 871155
Fax : (49)(0)5034 92579
www : http://www.tzv.fal.de/~eg/
e-mail: eg(at)tzv(dot)fal(dot)de
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