EXPERT RESPONSE
Great question. Other regular Oracle readers of this column
must surely also have noticed the scarcity of Oracle examples.
A wee explanation is in order.
This column has always, since its inception over six years ago,
been about just SQL, with as few proprietary or non-standard wrinkles
as possible. (See the
list of expert categories.)
Naturally, as most of you are aware, standard SQL doesn't always work on
your database of choice, nor does it have what you could call
a robust set of functions (date calculation and string manipulation
come easily to mind). So the examples in the solutions often had
to use some particular flavour of SQL.
A few years later, TechTarget decided to re-align its "Search" portals
with technology platforms. Gone was the generic database web site, and
so this column had to be assigned elsewhere. SearchOracle.com
is where it ended up. Unfortunately, PL/SQL is the weakest of my SQL
dialects, which is why there are so few Oracle examples.
Reader Pete from Sheffield, who asked this follow-up question, was
kind enough to provide the following Oracle code:
CREATE OR REPLACE FUNCTION is_numeric (p_in VARCHAR2)
RETURN VARCHAR2
IS
/* Returns 'T' if the value is NUMERIC 'F' otherwise */
l_temp NUMBER;
l_return VARCHAR2(1) := 'F';
BEGIN
SELECT p_in
INTO l_temp
FROM DUAL;
l_return := 'T';
RETURN l_return;
EXCEPTION
WHEN OTHERS
THEN
RETURN l_return;
END;
/
Thanks, Pete!
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