code: protected Collection<String> getFKRemovingScripts()
     {
        List<String> scripts = new ArrayList<String>();
  
        String constraintName = "JCR_FK_" + itemTableSuffix + "_PARENT";
        scripts.add("ALTER TABLE " + itemTableName + " " + constraintDroppingSyntax() + " " + constraintName);
  
        return scripts;
     }
docs: Returns SQL scripts for removing FK on JCR_ITEM table.