Hibernate Many-To-One Foreign Key Default 0

Question

I have a table where the the parent object has an optional many-to-one relationship. The problem is that the table is setup to default the fkey column to 0.

When s

Answer 1

I was able to fix this by creating an id-long type which extends the built in Long type, but if the id returned from SQL was 0, return null instead. This kept the allowance of default 0s in our DB while getting hibernate to stop doing lazy fetches.

public class IdentifierLongType extends LongType implements IdentifierType {

@Override
public Object get(ResultSet rs, String name) throws SQLException {
    long i = rs.getLong(name);
    if (i == 0) {
        return null;
    } else {
        return Long.valueOf(i);
    }
}

}

The reason for enforcing explicit default 0 is that Oracle handles indexing and null values oddly, suggesting better query performance with explicit values vs. 'where col is [not] null'