对于想了解java.sql.SQLException：在mysql中结果集结束后的读者，本文将是一篇不可错过的文章，我们将详细介绍sql结果集已耗尽，并且为您提供关于AWSRDS：java.sql.S

对于想了解java.sql.SQLException：在mysql中结果集结束后的读者，本文将是一篇不可错过的文章，我们将详细介绍sql结果集已耗尽，并且为您提供关于AWS RDS：java.sql.SQLException：用户、com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException：SQL语法错误、DB2 升级产生 java.sql.SQLException：无效的列名、java.sql.SQLException: com.mysql.jdbc.Driver的有价值信息。

• java.sql.SQLException：在mysql中结果集结束后（sql结果集已耗尽）
• AWS RDS：java.sql.SQLException：用户
• com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException：SQL语法错误
• DB2 升级产生 java.sql.SQLException：无效的列名
• java.sql.SQLException: com.mysql.jdbc.Driver

java.sql.SQLException：在mysql中结果集结束后（sql结果集已耗尽）

我正在尝试从MYSQL下载图像（.png）文件。有时它工作正常。无法找到确切的问题。它可以在Jboss服务器上正常工作。尝试在Apche上的本地计算机中运行时引发错误。

请帮助我修复错误。这是我的Java代码。

    try {        conection = SQLUtil.createConnection(Constant.DataSourceName);        st = conection.prepareStatement("SELECT image FROM TABLE_NAME WHERE Userid="+ getUserId());        result = st.executeQuery();        result.next();        if(!result.next()){        input = result.getAsciiStream(1);        }        FileOutputStream output = new FileOutputStream(getSignatureImageDestinationPath());        int ch = input.read();        while (ch != -1) {            output.write((char) ch);            ch = input.read();        }        output.close();        input.close();        result.close();        SQLUtil.closeConnection(conection);    } catch (Exception e) {        System.out.println(e+":Error");    } finally {        if (st != null) {            SQLUtil.closeConnection(conection);        }    }

这是堆栈跟踪输出：

java.sql.SQLException: After end of result setat com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1074)at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:988)at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:974)at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:919)at com.mysql.jdbc.ResultSetImpl.checkRowPos(ResultSetImpl.java:854)at com.mysql.jdbc.ResultSetImpl.getAsciiStream(ResultSetImpl.java:1275)at org.apache.tomcat.dbcp.dbcp.DelegatingResultSet.getAsciiStream(DelegatingResultSet.java:253)at org.apache.tomcat.dbcp.dbcp.DelegatingResultSet.getAsciiStream(DelegatingResultSet.java:253)at com.ninenexus.model.Signature.getSignatureImage(Signature.java:173)at com.ninenexus.servlets.SaveMySignature.mySignatureDisplay(SaveMySignature.java:69)at com.ninenexus.servlets.SaveMySignature.doPost(SaveMySignature.java:35)at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:306)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161)at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:380)at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:243)at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:188)at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:288)at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)at java.lang.Thread.run(Unknown Source)

答案1

您打了result.next()两次电话。我假设您的查询仅返回1行，因为您尝试通过进行匹配Userid。当第二个result.next()被调用时，中没有要返回的行ResultSet。这就是SQLException抛出an的原因。result.next()像这样删除第一个：

result = st.executeQuery();if(!result.next()){    input = result.getAsciiStream(1);    }

AWS RDS：java.sql.SQLException：用户

AmazonRDSDataFullAccess策略用于与无服务器RDS数据API进行交互。它不提供执行IAM身份验证的标准数据库连接所需的适当权限。您需要遵循指南here来创建适当的策略。特别是，您需要授予EC2实例配置文件rds-db:connect权限。

您可以尝试以下操作：

1. 尝试重新创建数据库用户并再次授予它权限
2. 代替内联策略，尝试使用客户托管策略，直到解决连接问题
3. 内联策略中的资源ARN后面有一个逗号，也应将其删除。

我将策略附加到EMR角色，我不得不将其附加到EMR集群的EC2实例配置文件中

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException：SQL语法错误

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'insert into customerLogin(companyName,username,password) values('Big Company','D' at line 1
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
    at com.mysql.jdbc.Util.getInstance(Util.java:386)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1054)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4187)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4119)
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2570)
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2731)
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2815)
    at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155)
    at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2458)
    at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2375)
    at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2359)
    at dao.CustomerContactDAO.performUpdate(CustomerContactDAO.java:175)
    at dao.DAOTemplate.executeUpdate(DAOTemplate.java:27)
    at dao.CustomerContactDAO.addCustomerContact(CustomerContactDAO.java:88)
    at test.Test.main(Test.java:29)

public boolean addCustomerContact(CustomerContact c) {
    setQuery("insert into customerContact(companyName,lastName,firstName,email,telNum,local,cellNum) values(?,?,?);"
            + "insert into customerLogin(companyName,password) values(?,?)");
    queries.add(getQuery());

    KeyValuePair onePair;

    onePair = new KeyValuePair();
    onePair.setKey(KeyValuePair.STRING);
    onePair.setValue(c.getCompanyName());
    getParameters().add(onePair);

    onePair = new KeyValuePair();
    onePair.setKey(KeyValuePair.STRING);
    onePair.setValue(c.getLastName());
    getParameters().add(onePair);

    onePair = new KeyValuePair();
    onePair.setKey(KeyValuePair.STRING);
    onePair.setValue(c.getFirstName());
    getParameters().add(onePair);

    onePair = new KeyValuePair();
    onePair.setKey(KeyValuePair.STRING);
    onePair.setValue(c.getEmail());
    getParameters().add(onePair);

    onePair = new KeyValuePair();
    onePair.setKey(KeyValuePair.INT);
    onePair.setValue(c.getTelNum() + "");
    getParameters().add(onePair);

    onePair = new KeyValuePair();
    onePair.setKey(KeyValuePair.INT);
    onePair.setValue(c.getLocal() + "");
    getParameters().add(onePair);

    onePair = new KeyValuePair();
    onePair.setKey(KeyValuePair.STRING);
    onePair.setValue(c.getCellNum() + "");
    getParameters().add(onePair);

    onePair = new KeyValuePair();
    onePair.setKey(KeyValuePair.STRING);
    onePair.setValue(c.getCompanyName());
    getParameters().add(onePair);

    onePair = new KeyValuePair();
    onePair.setKey(KeyValuePair.STRING);
    onePair.setValue(c.getUsername());
    getParameters().add(onePair);

    onePair = new KeyValuePair();
    onePair.setKey(KeyValuePair.STRING);
    onePair.setValue(c.getPassword());
    getParameters().add(onePair);
    return executeUpdate();
}

DB2 升级产生 java.sql.SQLException：无效的列名

<dependency>
   <groupId>mysql</groupId>
   <artifactId>mysql-connector-java</artifactId>
   <version>5.1.38</version>
</dependency>