Hi,
This is the 1st time I'm writing a SQL program. I understand that there's such a function, Isnumeric(field name). It is able to check a field content to ensure it's all numeric. But I faced problems when using it. Do I have to create the function in order to use it or is it inbuilt in the server? Is there any other ways I can validate a String field to ensure its content is numerical? By the way, I'm working in the IBM AS400 environment.

Eg. 000AK78 - Returns false
0004589 - Returns true

Your help is greatly appreciated.

Unless you write the function yourself, I don't beleive AS400 SQL has an "isnumeric" function.

Yupyup you are right.
Read up some articles and learnt that I've got to add the function before I can use it in AS400 SQL.