Convert char to number ?

From: <tjmxyz_at_my-deja.com>
Date: Wed, 24 Jan 2001 15:34:32 GMT
Message-ID: <94msm7$7ds$1@nnrp1.deja.com>

Simple question..

I have a column markcol1
I need to convert it to a number and sum it but I can't guarantee all values will be numbers..

For example
MARKCOL1

---

abc
10
0
.NULL.
12

IF I do...
SELECT SUM(TO_NUMBER(markcol1)) from mytable;

I get...

ORA-01722: invalid number

How do I ignore any character expressions....

Tried also
SELECT SUM(TO_NUMBER(NVL(markcol1,0))) from mytable;

But of course that did not work...

What do I use?

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http://www.deja.com/ Received on Wed Jan 24 2001 - 09:34:32 CST