string themeQuery = "SELECT * FROM Theme";
using (SQLiteCommand command = new SQLiteCommand(themeQuery, externalConnection))
using (SQLiteDataReader reader = command.ExecuteReader())
{
    while (reader.Read())
    {
        int oldThematicId = Convert.ToInt32(reader["ThematicId"]);
        int newThematicId = thematicMapping[oldThematicId];
        string name = reader["Name"].ToString();
        InsertTheme(newThematicId, name);
        int newId = GetLastInsertId();
        themeMapping[Convert.ToInt32(reader["Id"])] = newId;
    }
}

string questionQuery = "SELECT * FROM Question";
using (SQLiteCommand command = new SQLiteCommand(questionQuery, externalConnection))
using (SQLiteDataReader reader = command.ExecuteReader())
{
    while (reader.Read())
    {
        int oldThemeId = Convert.ToInt32(reader["ThemeId"]);
        int newThemeId = themeMapping[oldThemeId];
        string text = reader["Text"].ToString();
        InsertQuestion(newThemeId, text);
        int newId = GetLastInsertId();
        questionMapping[Convert.ToInt32(reader["Id"])] = newId;
    }
}

string themeQuery = "SELECT * FROM Theme";
using (SQLiteCommand command = new SQLiteCommand(themeQuery, externalConnection))
using (SQLiteDataReader reader = command.ExecuteReader())
{
    while (reader.Read())
    {
        int oldThematicId = Convert.ToInt32(reader["ThematicId"]);
        int newThematicId = thematicMapping[oldThematicId];
        string name = reader["Name"].ToString();
        InsertTheme(newThematicId, name);
        int newId = GetLastInsertId();
        themeMapping[Convert.ToInt32(reader["Id"])] = newId;
    }
}

string questionQuery = "SELECT * FROM Question";
using (SQLiteCommand command = new SQLiteCommand(questionQuery, externalConnection))
using (SQLiteDataReader reader = command.ExecuteReader())
{
    while (reader.Read())
    {
        int oldThemeId = Convert.ToInt32(reader["ThemeId"]);
        int newThemeId = themeMapping[oldThemeId];
        string text = reader["Text"].ToString();
        InsertQuestion(newThemeId, text);
        int newId = GetLastInsertId();
        questionMapping[Convert.ToInt32(reader["Id"])] = newId;
    }
}