String values discarded after calling Commit() method

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String values I add into into a S column of a c4_View are apparently discar=
ded after calling the Commit() method from the C++ API. See this code:

#include <iostream>
#include <map>
#include <mk4.h>
#include "database.h"

using namespace std;

database::database (string file_name)
: connection_handler (file_name.c_str (), 1),
  table_tracks       (connection_handler.GetAs ("tracks [degrees:D, compass=
:S]"))
{
  cout << "Opening database " << file_name << "." << endl;

  if (table_tracks.GetSize () =3D=3D 0) {
    c4_DoubleProp degrees ("degrees");
    c4_StringProp compass ("compass");
    c4_Row        track;
    int           i;
    string        compass_points [17] =3D {"N", "NNE", "NE", "ENE",
                                         "E", "ESE", "SE", "SSE",
                                         "S", "SSW", "SW", "WSW",
                                         "W", "WNW", "NW", "NNW",
                                         "N"};

    cout << "Database is vanilla. Setting it up now." << endl;

    for (i =3D 0; i <=3D 16; i++) {
      degrees (track) =3D 22.5 * (double) i;
      compass (track) =3D (compass_points [i]).c_str ();

      table_tracks.Add (track);
    }

    for (i =3D 0; i < table_tracks.GetSize (); i++) {
      cout << (double) degrees (table_tracks [i]) << " " << (string) compas=
s (table_tracks [i]) << endl;
    }

    connection_handler.Commit ();

    for (i =3D 0; i < table_tracks.GetSize (); i++) {
      cout << (double) degrees (table_tracks [i]) << " " << (string) compas=
s (table_tracks [i]) << endl;
    }
  }
}

In the loop before the Commit(), I get the contents of both columns (#1 =E2=
=86=92 double; #2 =E2=86=92 string; hope I did the syntax right in the GetA=
s() method), but in the loop following the commit, the contents of column #=
2 don't appear any more!

My version of Metakit is 2.4.9.7 on a Raspberry Pi.

What's wrong here? Thank you for any useful hint.
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