Spring JdbcTemplate选择别名表列

Question

JdbcTransfersDao。java：

//row mapper
private TransfersHistory mapRowsToTransfersHistory(SqlRowSet rowset){
    TransfersHistory newTransfersHistory = new TransfersHistory();
    newTransfersHistory.setTransferId(rowset.getInt("transfer_id"));
    newTransfersHistory.setToFrom(rowset.getString("to_from"));
    newTransfersHistory.setAmount(rowset.getBigDecimal("amount"));

    return newTransfersHistory;
}

public TransfersHistory[] transfersHistoryByUserId(int loggedInUser){

    String sqlTransfersHistory = "select t.transfer_id, 'to: '||(select username from users as fu join accounts fa on fu.user_id = fa.user_id where account_id = t.account_from) as to_from, t.amount from transfers as t" +
            " where" +
            " t.account_to = (select account_id from accounts as ta join users tu on ta.user_id = tu.user_id where tu.user_id= ?)" +
            " union" +
            " select t.transfer_id, 'from: '||(select username from users as fu join accounts fa on fu.user_id = fa.user_id where account_id = t.account_to) as to_from, t.amount from transfers as t" +
            " where" +
            " t.account_from = (select account_id from accounts as ta join users tu on ta.user_id = tu.user_id where tu.user_id= ?);";
    
    SqlRowSet rs = jdbcTemplate.queryForRowSet(sqlTransfersHistory, loggedInUser);
    rs.getMetaData();
    List<TransfersHistory> tempTransfersHistory = new ArrayList<>();
    while (rs.next()){
        tempTransfersHistory.add(mapRowsToTransfersHistory(rs));
    }
    TransfersHistory[] tempTransferHistoryArr = new TransfersHistory[tempTransfersHistory.size()];
    tempTransfersHistory.toArray(tempTransferHistoryArr);
    return tempTransferHistoryArr;
}

控制器。Java语言

public List<TransfersHistory> transfersHistory(String base_url, AuthenticatedUser authenticatedUser){
    HttpHeaders headers = setupAuth(authenticatedUser);
    HttpEntity<?> entity = new HttpEntity<>(headers);
    ResponseEntity<TransfersHistory[]> res =  restTemplate.exchange(base_url + transfers_history_resource, HttpMethod.POST, entity, TransfersHistory[].class);
    List<TransfersHistory> tempTransfers = new ArrayList<>();
    tempTransfers = Arrays.asList(res.getBody());
    return tempTransfers;
}

转让。Java语言

public class TransfersHistory {
    private int transferId;
    private String toFrom;
    private BigDecimal amount;
}

Answer 1

找到了答案。看起来像是<代码>。queryForRowSet（）和。queryForObject（）不喜欢SQL联合运算符，所以我不得不使用myPreparedStatement。executeQuery（mySql）。