Question

我是新手，并尝试使用预处理语句将一些日期添加到Oracle数据库中。这是我的代码：

CODE REMOVED, code updated.

这会产生以下结果：

INSERT into TEST_RESULTS12233 (DB_ID, DATED1, DATED2, DATED3, DATED4) values (t1_seq.nextval, to_date(?, 'dd/mm/yyyy hh24.mi'), to_date(?, 'dd/mm/yyyy hh24.mi'), to_date(?, 'dd/mm/yyyy hh24.mi'), to_date(?, 'dd/mm/yyyy hh24.mi'))
Event1
Event2
Event3
Event4
Exception in thread "main" java.sql.BatchUpdateException: ORA-01858: a non-numeric character was found where a numeric was expected

at oracle.jdbc.driver.OraclePreparedStatement.executeBatch(OraclePreparedStatement.java:10500)
at oracle.jdbc.driver.OracleStatementWrapper.executeBatch(OracleStatementWrapper.java:230)
at sandpit.testsand.main(testsand.java:85)

如果我将setString中的pstatement替换为Event1，则批处理执行。有谁知道我怎么能让这个工作？感谢

以下是所要求的完整代码：

     //MORE CODE AS REQUESTED 


     String inserttotable = "INSERT into TEST_RESULTS12233 (DB_ID";
     String stateclose = ")";
     String insertvalues =(" values (t1_seq.nextval");
     StringBuilder insertBuilder = new StringBuilder();
     StringBuilder valueBuilder = new StringBuilder();
     int timestoloop = 4;

     for (i=1; i<=timestoloop; i++)

     {           
         insertBuilder.append(", DATED"+i);
         valueBuilder.append(", to_date(?, 'dd/mm/yyyy hh24.mi')");

     }

     String finalinsert = inserttotable + insertBuilder.toString()+ stateclose;
     String finalvalues = insertvalues + valueBuilder.toString() + stateclose;
     String insertsql = finalinsert + finalvalues;
     System.out.println(insertsql);
     String insertresults = insertsql;

        PreparedStatement prepState = conn.prepareStatement(insertresults);


    String Event1 = "22122014 13.26";
    String Event2 = "22122014 13.27";
    String Event3 = "22122014 13.28";
    String Event4 = "22122014 13.29"; 


     for (i=1; i<=timestoloop; i++)

     {           
        String pstatement = "Event"+i;
        System.out.println(pstatement);
        prepState.setString(i, pstatement);


     }

     prepState.addBatch();
     prepState.executeBatch();

Answer 1

通过将计数器附加为String文字（Event1）并将其作为String输入设置为预准备语句，您可以动态创建变量名称。您实际上是设置String文字，如（Event1）而不是值（22122014 13.26）。这不是您应该做的方式。您可能必须直接设置值，如

 prepState.setString(1, Event1);
 prepState.setString(2, Event2);
 prepState.setString(3, Event3);
 prepState.setString(4, Event4);

我建议你去找一个包含所有Event值的String文字列表。迭代它们并在Prepared语句中设置它们并执行查询。

List<String> eventValues = new ArrayList<String>();

Answer 2

我相信你提到你已经尝试了一个arraylist但它应该看起来像这样：

List<String> events=new ArrayList<String>();
    events.add("22122014 13.26");
    events.add("22122014 13.27");
    events.add("22122014 13.28");
    events.add("22122014 13.29");


     for (i=1; i<=timestoloop; i++)

     {           
        String pstatement = "Event"+i;
        System.out.println(pstatement);
        prepState.setString(i, events.get(i));
        prepState.addBatch();
     }

你正在使用字符串＆＃34; Event1＆＃34;来自您的变量而不是实际变量。 prepState.setString（i，＆＃34; event＆＃34; + i）不等于prepState.setString（i，event1）。一个只返回一个字符串，一个只是一个包含字符串值的变量，后者是你想要的那个。

Java Prepared Statement不能与我的循环一起使用

2 个答案: