[odb-users] Containers of containers

[Boris Kolpackov]

MM <finjulhich at gmail.com> writes:

> > My use case is a little extra on top of the vector<trip> case.
> > What is *trip* is not actually just a vector<country_stay> but somethine
> > like
> >
> > struct trip {
> >    double d1;
> >    int d2;
> >    vector<country_stay> d3;
> > };
> >
> > how do I change that example code?
> 
> Does the mechanism only work if the member type is
> std::vector<std::vector<T>>?

The second example in person.hxx seems to illustrate exactly what you
are trying to achieve:

// vector<struct{vector<value>}>
//
using phone_numbers = std::vector<std::string>;

#pragma db value
struct emergency_contact
{
  std::string first_name;
  std::string last_name;

  #pragma db transient // Note: replaced with virtual below.
  phone_numbers numbers;
};

using emergency_contacts = std::vector<emergency_contact>;