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下面的类会将.csv导入数据库表。它工作正常,现在我需要更新同一个表中的另一列,当在数据库表的相应列中执行该程序时,需要更新当前系统时间戳。

示例:在 Db2 表中,主题列是:Eng Social Maths TimeStamp

在 .CSV 文件中只有 3 列 Eng Social Maths 。

当 .csv 文件被导入(使用上述程序)到 db2 时,除了 TimeStamp 之外,所有列都会更新。时间戳用于记录 .csv 文件何时上传到表格。那么,如何同时使用当前系统时间戳更新 TimeStamp 列。?请帮忙

公共类 CSVLoader {

private static final 
    String SQL_INSERT = "INSERT INTO OPPTYMGMT.${table}
         (${keys})      VALUES(${values})";

private static final String TABLE_REGEX = "\\$\\{table\\}";

private static final String KEYS_REGEX = "\\$\\{keys\\}";

private static final String VALUES_REGEX = "\\$\\{values\\}";

private Connection connection;

private char seprator;

public CSVLoader(Connection connection) {

    this.connection = connection;

    //Set default separator

    this.seprator = ',';
}

      public void loadCSV(String csvFile, String tableName) throws Exception {

    CSVReader csvReader = null;

    if(null == this.connection) {

        throw new Exception("Not a valid connection.");
    }

    try {

        csvReader = new CSVReader(new FileReader(csvFile), this.seprator);

    } catch (Exception e) {

        e.printStackTrace();

        throw new Exception("Error occured while executing file. "

                   + e.getMessage());

              }

        String[] headerRow = csvReader.readNext();

    if (null == headerRow) {

        throw new FileNotFoundException(


                        "No columns defined in given CSV file." +

                         "Please check the CSV file format.");
    }

    String questionmarks = StringUtils.repeat("?,", headerRow.length);

    questionmarks = (String) questionmarks.subSequence(0, questionmarks

            .length() - 1);


    String query = SQL_INSERT.replaceFirst(TABLE_REGEX, tableName);

    query = query
            .replaceFirst(KEYS_REGEX, StringUtils.join

             (headerRow,   ","));

    query = query.replaceFirst(VALUES_REGEX, questionmarks);

            System.out.println("Query: " + query);

    String[] nextLine;

    Connection con = null;

    PreparedStatement ps = null;

    try {
        con = this.connection;

        con.setAutoCommit(false);

        ps = con.prepareStatement(query);

                       final int batchSize = 1000;

                     int count = 0;

        Date date = null;

        while ((nextLine = csvReader.readNext()) != null) {

            System.out.println( "inside while" );

            if (null != nextLine) {

                int index = 1;

                for (String string : nextLine) {

                    date = DateUtil.convertToDate(string);

        if (null != date) {

                    ps.setDate(index++, new java.sql.Date(date

                    .getTime()));

                     } else {

                  ps.setString(index++, string);

    System.out.println( "string" +string);

                    }

                }

                ps.addBatch();

            }

            if (++count % batchSize == 0) {

                ps.executeBatch();

            }

                     }


        ps.executeBatch(); // insert remaining records

        con.commit();

    } catch (Exception e) {

        con.rollback();

        e.printStackTrace();

        throw new Exception(

        "Error occured while loading data 

                from file                to                      database."

               + e.getMessage());

    } finally {

             if (null != ps)


            ps.close();

        if (null != con)

            con.close();

            System.out.println("csvReader will be closed");

        csvReader.close();

    }

}

public char getSeprator() {

    return seprator;

}

public void setSeprator(char seprator) {

    this.seprator = seprator;

}


         }
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3 回答 3

3
private static final 
 String SQL_INSERT = "INSERT INTO OPPTYMGMT.${table}
     (${keys}, my_timestamp_column)      VALUES(${values}, current_timestamp)";
于 2013-08-14T13:03:20.807 回答
0

当使用表达当前系统时,它可能表示执行 Java 的系统或执行 DB2 的系统。

您可以通过上一个答案获取 Java 日期。

对于 DB2 日期,您应该在插入语句中提供此日期

current date

例如,对于一个表

create table t1 (date date)

insert into t1 values (current date)

最后,如果您真的想将数据导入 DB2,最好使用 IMPORT 或 LOAD 命令,而不是重新创建您自己的工具。

于 2013-08-14T10:09:15.363 回答
0
SimpleDateFormat cDate = new SimpleDateFormat("yyyy-MM-dd HH-mm-ss");
Date now = new Date();
String ccDate = cDate.format(now);

将获取当前时间并将字符串 ccDate 插入数据库。 例子

于 2013-08-14T07:17:18.600 回答