default Optional<? extends PrimaryKeyColumn> findPrimaryKeyColumn(String id) {
        return primaryKeyColumns().filter(child -> child.getId().equals(id)).findAny();
    }
Locate the {@link PrimaryKeyColumn} child with the specified id if it
exists, else return an empty {@code Optional}.

@param id  the {@link HasId#getId()} of the primary key column
@return    the child found or an empty {@code Optional}
runtime-parent/runtime-config/src/main/java/com/speedment/runtime/config/Table.java