DBMS_METADATA.get_ddl error

[jmodic]

The problem here seems to be with NOT NULL constraints that are system generated as CHECK constraints. Those constraints seems to be correctly incorporated in CRATE TABLE generated with DBMS_METADATA('TABLE', table_name), but fail with DBMS_METADATA('CONSTRAINT, constraint_name).

I thought those system-generated NOT NULL check constraints could be filtered out by using (this should be at least the closest approximation):

SELECT DBMS_METADATA.get_ddl('CONSTRAINT' ,constraint_name)
FROM USER_CONSTRAINTS
WHERE NOT (constraint_type = 'C' AND AND search_condition LIKE '%" NOT NULL';)

but unfortuantely the column SEARCH_CONDITION in USER_CONSTRAINTS is of type long.

So I guess the closest approximation you could get with those check constraints would be

SELECT DBMS_METADATA.get_ddl('CONSTRAINT' ,constraint_name)
FROM USER_CONSTRAINTS
WHERE NOT (constraint_type = 'C' AND GENERATED = 'GENERATED NAME');

This of course could filter out some o your "something-different-than-not-null-check-costraint" that you didn't bother to name explicitely.