class Foo
{
  static int ReadSelfFromBase(void *userarg, int argc, char **argv, char **ColName){...}

public:
  void Bar(sqlite3* db)
  {
    ...
    rc = sqlite3_exec(db, "select * from test", &ReadSelfFromBase, this, &zErrMsg);
    ...
  }
}

int main()
{
Foo test;
...
test.Bar(db);
}

int main()
{
   rc = sqlite3_exec(db, "select * from test", Foo::ReadSelfFromBase, NULL, &zErrMsg);
}