[odb-users] Avoid copying objects from odb::result

[aongeeno at openmailbox.org]

Good day! How I can avoid copying objects in this code?

PRAGMA_DB(object)
struct Category
{
    Category() {}
    PRAGMA_DB(member id)
    CategoryID id        = -1;
    QString    name;
private:
    friend class odb::access;
};

/* ............................*/

std::unordered_map<int, std::unique_ptr<Category>> categories;

/* ............................*/

auto result(db_->query<Category>());
for (Category & c : r)
    //categories[c.id] = std::make_unique(c); ???