这个特定的别名SQL列是否存在问题？

Question

为什么在select语句中使用别名时会将别名视为外星人？

我无法想象总是如此，但我不得不改变这段代码：

const string query = 
    @"SELECT C.PLATYPUSCLIENTID, E.DEWDROPNAME FOGGY
    FROM DUCKBILLACCOUNT B,
        PLATYPUSCLIENT C,
        ENTITY E
    WHERE B.DUCKBILLNUMBER = :PLATYPUSACCOUNTID
        AND B.DUCKBILLACCOUNTABCID = C.DUCKBILLACCOUNTABCID
        AND C.PLATYPUSCLIENTABCID = E.ABCID
    ORDER BY FOGGY, PLATYPUSCLIENTID";
    try {
        oc.Open();
        using (OracleCommand ocmd = new OracleCommand(query, oc)) {
            ocmd.Parameters.Add("PLATYPUSACCOUNTID", PLATYPUSACCOUNTID);
            using (OracleDataReader odr = ocmd.ExecuteReader()) {
                while (odr.Read()) { . . .

......对此：

const string query = 
    @"SELECT C.PLATYPUSCLIENTID, E.DEWDROPNAME 
    FROM DUCKBILLACCOUNT B,
        PLATYPUSCLIENT C,
        ENTITY E
    WHERE B.DUCKBILLNUMBER = :PLATYPUSACCOUNTID
        AND B.DUCKBILLACCOUNTABCID = C.DUCKBILLACCOUNTABCID
        AND C.PLATYPUSCLIENTABCID = E.ABCID
    ORDER BY DEWDROPNAME, PLATYPUSCLIENTID";
    try {
        oc.Open();
        using (OracleCommand ocmd = new OracleCommand(query, oc)) {
            ocmd.Parameters.Add("PLATYPUSACCOUNTID", PLATYPUSACCOUNTID);
            using (OracleDataReader odr = ocmd.ExecuteReader()) {
                while (odr.Read()) { . . .

...让它在运行时返回vals（我得到＆＃34; IndexOutOfRangeException＆＃34;第一个版本）

Answer 1

您需要引用别名。

E.DEWDROPNAME 'FOGGY' ...