从Java SQL阵列获取的ResultSet失败 [英] Java get ResultSet from SQL Array is Failing

问题描述

我试着从数据库中检索电子邮件地址，但我没有成功。我的code是如下：

Im trying to retrieve email addresses from a database but am not having success. My Code is as Follows:

主营：

System.out.println(PortfolioData.getEmails(58));  //So Far Returning null

PortfolioData：

public static String[] getEmails(int i){    
    DebugMessage.M("Retrieving Email Records for Person Key Number: " + i);
    eq.query("SELECT EmailAddresses"
            + " FROM Emails as E"
            + " JOIN People AS P ON E.PersonKey = P.PersonKey"
            + " WHERE P.PersonKey = ?",i);
    return (String[])eq.getOnceMultipleRows("EmailAddresses");
}

DBEasyQuery：

public Object getOnceMultipleRows(String label){
    if(next()){
        try {   
            Array a = rs.getArray(label);
            String[] x = (String[])a.getArray();
            smartClose();
            return x;
            //return rs.getArray(label).getArray();
        } catch (SQLException e) {
            DebugMessage.E("getOnceMultipleRows() Failed on Query: " + queryExecuted());
            DebugMessage.E("getOnceMultiple() Failed on Label: " + label );
            notExecuted(e);
        }   
    }
    smartClose();
    return null;
}

下面是我的日志文件和错误：

Here is my log file and errors:

MESSAGE:   Retrieving Person Records for Person Key Number: 58
MESSAGE:   SharedConnection dziemba created
SQLQUERY:    SELECT AlphaID, FirstName, LastName, Street, City, State, Zip, Country, AcctType, SecID FROM People AS P JOIN Addresses AS A ON P.PersonKey = A.PersonKey LEFT JOIN Role AS R ON P.PersonKey = R.PersonKey WHERE P.PersonKey = 58
MESSAGE:   Retrieving Email Records for Person Key Number: 58
SQLQUERY:    SELECT EmailAddresses FROM Emails as E JOIN People AS P ON E.PersonKey = P.PersonKey WHERE P.PersonKey = 58
ERROR:   getOnceMultipleRows() Failed on Query:  SELECT EmailAddresses FROM Emails as E JOIN People AS P ON E.PersonKey = P.PersonKey WHERE P.PersonKey = 58
ERROR:   getOnceMultiple() Failed on Label: EmailAddresses
ERROR:   
 The Following Query Was NOT Executed:
 SELECT EmailAddresses FROM Emails as E JOIN People AS P ON E.PersonKey = P.PersonKey WHERE P.PersonKey = 58
 Stack Trace:
ERROR:   sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
ERROR:   sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
ERROR:   sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
ERROR:   java.lang.reflect.Constructor.newInstance(Unknown Source)
ERROR:   java.lang.Class.newInstance(Unknown Source)
ERROR:   com.mysql.jdbc.SQLError.notImplemented(SQLError.java:1334)
ERROR:   com.mysql.jdbc.ResultSetImpl.getArray(ResultSetImpl.java:1230)
ERROR:   com.mysql.jdbc.ResultSetImpl.getArray(ResultSetImpl.java:1247)
ERROR:   unl.cse.DBEasyQuery.getOnceMultipleRows(DBEasyQuery.java:218)
ERROR:   unl.cse.PortfolioData.getEmails(PortfolioData.java:136)
ERROR:   unl.cse.Main.main(Main.java:44)
ERROR:   

Kayaman评论说我的错误日志不显示实际例外。所以，我已经打消了我的错误日志记录和捕捉。这里是什么我现在在终端获得：

Kayaman commented that my error log wasn't showing the actual exception. So I've removed my error logging and catching. Here is what I'm now getting in the terminal:

[Ljava.lang.String;@59966240
java.sql.SQLFeatureNotSupportedException
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at java.lang.Class.newInstance(Unknown Source)
    at com.mysql.jdbc.SQLError.notImplemented(SQLError.java:1334)
    at com.mysql.jdbc.ResultSetImpl.getArray(ResultSetImpl.java:1230)
    at com.mysql.jdbc.ResultSetImpl.getArray(ResultSetImpl.java:1247)
    at unl.cse.DBEasyQuery.getOnceMultipleRows(DBEasyQuery.java:220)
    at unl.cse.PortfolioData.getEmails(PortfolioData.java:136)
    at unl.cse.Main.main(Main.java:44)
Exception in thread "main" java.lang.NullPointerException
    at unl.cse.DBEasyQuery.getOnceMultipleRows(DBEasyQuery.java:227)
    at unl.cse.PortfolioData.getEmails(PortfolioData.java:136)
    at unl.cse.Main.main(Main.java:44)

查询本身的MySQL工作台内执行罚款：

The query itself executes fine inside MySQL Workbench:

有些DBEasyQuery的额外支持code可以在下面的图片中找到。我从后显示，因为它使后很长删除它： HTTP：//i.stack .imgur.com / WZDkL.png

Some of the additional supporting code of DBEasyQuery can be found in the below picture. I removed it from showing in the post since it makes the post really long: http://i.stack.imgur.com/WZDkL.png

我不认为在这一个错误，因为它工作正常，一切我可以扔了：

I don't think there is an error in it since it works fine for everything else I can throw at it:

推荐答案

问题是在JDBC驱动程序。并非所有的驱动程序支持所有功能，并且您正在使用的驱动程序不支持这一点。

The problem is in the JDBC driver. Not all drivers support all features, and the driver you're using doesn't support this.

解决方案：找到支持的功能（如果存在）不同的驱动程序

Solutions: find a different driver that supports the feature (if one exists).

编辑：
它看起来并不驾驶员侧太好。您可能需要不同的执行查询。

It doesn't look too good on the driver side. You might have to perform your queries differently.

编辑＃2：似乎 MySQL不支持数组类型所以你需要做的事情的老式方法。

EDIT #2: It seems that MySQL doesn't support the ARRAY type so you will need to do things in the old fashioned way.

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