Currently, if during the RegenerateUrlAliasesCommand execution parent url alias cannot be found, "0" is written in the parent column. "0" is also an id representing the root Content, which causes malfunction. Ideally, the RegenerateUrlAliasesCommand should report an error if the parent differs from the root content, but cannot be found.

Related issue: EZP-28740 (wrong url aliases were created, but no error was reported).