constraint creation problems

I'm trying to add a constraint that will check the firt letter of a VARCHAR type to make sure its first letter is a letter not a number and second to make sure it is in uppercase but I haven't the faintest idea how to do it.

Does sqlplus support character indexind, in wich case I could probably do something like?:

AttributeName(1) BETWEEN 'A' AND 'Z'...

Or do I have to create a domain and check if the forst character of the varchar is in the domain?

And how do I select only the first character for my checking purposes?

Any reply will be greatly appreciated!Try this (In Oracle):

alter table MyTable
add constraint chk_UPPER1
check(nvl(substr(AttributeName,1,1),'?') between 'A' and 'Z');

;)|||Originally posted by LKBrwn_DBA
Try this (In Oracle):

alter table MyTable
add constraint chk_UPPER1
check(nvl(substr(AttributeName,1,1),'?') between 'A' and 'Z');

;)

Thanks a bunch!

Since I'm creating the table can do this?

CREATE tableName
(AttributeName varchar(8) not null,
CONSTRAINT chk_upper1
check(nvl(substr(AttributeName,1,1),'?') between 'A' and 'Z')
)

P.S. I'm not sure if the nvl will work in oracle8 its sqlplus... Than I suppose that I can do it with decode...

Thanks again!|||Yes, NVL will work in Oracle8 and yes you can define the constraint in the 'create table'

:D|||Originally posted by LKBrwn_DBA
Yes, NVL will work in Oracle8 and yes you can define the constraint in the 'create table'

:D

Thanks!