FAQ

Q1. not a valid database user: <db-user-name>

In the nc_databaseuser database table there needs to be a record for the database user '<db-user-name>'. Since every table has mandatory OWNER and MODUSER columns in order to be able to insert any records you need to have a record for the database connection user name in the nc_databaseuser table.

Another cause of this problem (if you have the necessary record in the database) is the case insensitivity of Oracle database users , while the nc_databaseuser name column is case sensitive. The user names must be entered as upper case to the nc_databaseuser table for equivalence checking.

Q2. error: ORA-02291: integrity constraint (<your-Oracle-schema>.FK_ASSESSMENT_SELF) violated - parent key not found.

The error you are seeing is a self referencing foreign key does not allow you to enter data. I am not sure about the utility of this specific foreign key, I have removed it in my database(s) using SQL like this

ALTER TABLE nc_assessment drop CONSTRAINT FK_ASSESSMENT_SELF;

Q3. error: ORA-02291: integrity constraint (<your-Oracle-schema>.FK_NC_ONTOLOGYSOURCENC_ONTOLOG) violated - parent key not found.

While currently there is no ontology, the ontology related tables needs to have some place holder records to satisfy the foreign keys. You can just insert a record to the nc_ontologysource table with column values