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Java JDBC结果集-Can';t检索别名列_Java_Sql_Jdbc - Fatal编程技术网

Java JDBC结果集-Can';t检索别名列

Java JDBC结果集-Can';t检索别名列,java,sql,jdbc,Java,Sql,Jdbc,我们有以下SQL查询: select Resa.ResID, Avgångdatum, Avgångtid, AvgångStad, AnkomstTid, AnkomstDatum, AnkomstStad, AntalPlatser, Kostnad, (select sum(Bokning.AntalBiljetter) from Bokning where Bokning.ResID = Resa.ResID) as EnkelBiljetter, (select s

我们有以下SQL查询:

select Resa.ResID, Avgångdatum, Avgångtid, AvgångStad, AnkomstTid, AnkomstDatum, AnkomstStad, AntalPlatser, Kostnad,

    (select sum(Bokning.AntalBiljetter) from Bokning where Bokning.ResID = Resa.ResID) as EnkelBiljetter,

    (select sum(Bokning.AntalBiljetter) from Bokning where Resa.ResID in
        (select PaketResa.ResID from PaketResa where PaketResa.PaketID in
            (select PaketID from PaketResa where PaketResa.PaketID = Bokning.PaketID))) as PaketBiljetter

from Resa;
当我们试图用java获取列“Enkelbiljetter”和“PaketBiljetter”时

Integer.parseInt(result.getObject("PaketBiljetter").toString()

它返回一个nullpointerexception。我们已尝试将“?
useOldAliasMetadataBehavior=true
”添加到连接语句中,但结果相同。将columnindex(10和11)放在getObject方法中也是如此。我们使用的是5.1.19 JDBC驱动程序。有什么建议吗

它可以是您的
结果
getObject(…)
返回空指针。由于有一个
getInt()
方法,您应该首先尝试以下方法:

result.getInt("PaketBiljetter")
看看会发生什么