Java 如何为“x”的n列设置列名

Hi以下查询正在返回：未为“t”的第1列指定列名

  public ArrayList<DocumentModel> findByDate(String code, String date, String dateFinal) throws GeneralException{
    ArrayList<DocumentModel> docs = new ArrayList<DocumentModel>();
    String d1 = date;
    String delimiter = "-";
    String[]temp = d1.split(delimiter);
    String[]temp2 = dateFinal.split("-");
    String num="";
    String alfa="";
    if (code.compareTo("")!=0){
        String[] c1 = code.split(",");
        num = c1[0];
        alfa = c1[1];
    }

    try{
        String sql = "SELECT max(issuedate),airlineOid as airlineNumericCode FROM Document  WHERE ";

        if (alfa.compareTo("")!=0) sql+=" airlineOid='"+alfa+"' and ";

        sql+=" convert(varchar,issueDate,112) >= '" + temp[0]+ temp[1] +"00'  AND convert(varchar,issueDate,112) < '"+ temp2[0]+ temp2[1] +"32' group by airlineOid";

        String sql2="select d.*,'"+num+"' as airlineNumericCode from document d,("+sql+") as t where t.airlineOid=d.airlineOid and t.issueDate=d.issueDate ORDER BY issueDate DESC ";

        ResultSet rs = this.executeQuery(sql2);
        while(rs.next()){
            docs.add((DocumentModel)this.build(rs));
        }
        if(docs != null){
            return docs;
        } else {
            return docs = null;
        }
    } catch (SQLException ex){
        throw new GeneralException(ex);
    }
}

我看不出应该在哪里指定名称。 非常感谢你！ 顺致敬意，

---

Ignacio

您需要向maxissuedate添加列别名，如下所示：

String sql = "SELECT max(issuedate) as MaxIssueDate, airlineOid as airlineNumericCode FROM Document  WHERE ";  

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我认为这是您的问题……您在SQL中将airline0id重命名为airlineNumericCode。然后，在sql2中，尝试将其称为airline0id。试试这个：

String sql = "SELECT max(issuedate) as issueDate,airlineOid as airlineNumericCode FROM Document  WHERE ";

...

String sql2="select d.*,'"+num+"' as airlineNumericCode from document d,("+sql+") as t where t.airlineNumericCode=d.airlineOid and t.issueDate=d.issueDate ORDER BY issueDate DESC ";

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您能在后台运行探查器并查看SQL server端实际执行的查询吗？不，我不能，非常感谢much@IgnacioGarat为什么不呢？如果是因为您有SQL Server的Express edition，请查看。您已经得到了答案，但在将来可能仍然有用。使用字符串sql=选择maxissuedate作为**maxissuedate**，airlineOid作为有效列名“airlineOid”。可能是吗？听起来第一个问题是，它没有第一列的名称或别名，而您现在发现的第二个问题是表文档中没有名为airlineOid的列。但我们必须查看表结构才能确定。我已经尝试过这样做，但现在得到了无效的列名“airlineOid”。