給定以下（MYSQL-）查詢：SELECT view_match_metric.player_id, discord_id, view_match_metric.name,   view_match_metric.xp AS xpthis, player.xp AS xptotal, ranked, mode, mu, sigma,   IF(team = 'Alpha', goals_alpha > goals_beta, goals_beta > goals_alpha) as won FROM view_match_metric LEFT OUTER JOIN kl_idmap ON view_match_metric.player_id = kl_idmap.player_id LEFT OUTER JOIN kl_trueelo ON view_match_metric.player_id = kl_trueelo.player_id LEFT OUTER JOIN player ON view_match_metric.player_id = player.player_id WHERE match_id="169498" 當我在我的數據庫程序（Adminer）上執行它時，它返回以下結果：請注意，它確實包含 xpthis 和 xptotal 的 int(10) 無符號條目然而在java中這個查詢拋出一個java.sql.SQLException: Invalid column nameat com.sun.rowset.CachedRowSetImpl.getColIdxByName(Unknown Source)at com.sun.rowset.CachedRowSetImpl.getInt(Unknown Source)對于 xpthis 和 xptotal 字段。它確實可以在沒有獲得這些字段的情況下工作。由于 xp 字段在多個表中不明確，我確實使用這些別名來指定它們。加載數據的代碼：while (result.next()) {    match.mode = result.getString("mode");    match.ranked = result.getBoolean("ranked");    TrueEloPlayerData player = new TrueEloPlayerData();    player.id = result.getLong("player_id");    player.discordID = result.getLong("discord_id");    player.name = result.getString("name");    //exception thrown in next line:    player.xp = result.getInt("xpthis");    player.level = Utility.getLevel(result.getInt("xptotal"));    //some more    match.players.add(player);}對于并行處理，通常的 ResultSet 被復制到 CachedRowSet 中：CachedRowSet res = RowSetProvider.newFactory().createCachedRowSet();res.populate(resultSet);我嘗試使用 getDouble、getString 獲取它們，甚至使用 getObject，嘗試直接訪問沒有別名的字段 (getInt(tablename.xp))，但它從未解決問題。我完全不知道為什么它在這里不能像在數據庫中那樣工作。