Re: users pasting hex '41' into char fields...

"MIDRANGE-L" <midrange-l-bounces@xxxxxxxxxxxx> wrote on 07/06/2016
10:54:16 AM:

currently this file is a legacy DDS file, but if I want to "reject" this
byte, as invalid data, as I am told our mySQL databases do, how would I
code my DDL?

Unfortunately, DDL doesn't have an efficient means of restricting
the value of character data. It can be done, but the overhead of doing so
is usually not acceptable. For example, an IBMer gave me the following as
the least expensive means of validating character data in DDL. The
following allows alphanumeric characters and blanks. I'd prefer a Regular
Expression for this but that may not be less overhead, either.

CONSTRAINT ACABBRVT_ABVCDE_CK01
CHECK(translate(ABBR_CODE, '1',
' abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789',
'1') = '1')

Sincerely,

Dave Clark