我是新手,并试图将数据帧写入db2表。我得到的错误是:
Exception in thread "main" java.lang.IllegalArgumentException: Can't get JDBC type for struct <data:int, day:int, hours:int, minutes:int, month:int, seconds:int, time:bigint, timeZoneOffset:int, year:int>
我的数据库架构是
localId <-- Integer type
effectiveDate <-- Timestamp
activityDate <-- Timestamp
inDate <-- Timestamp
outDate <-- Timestamp
我为我的db表创建了一个POJO类,就像这样
public class StowageTable {
private long localId;
private Date effectiveDate;
private Date activityDate;
private Date inDate;
private Date outDate;
//setters and getters
}
然后,我基本上读取了一个与db表具有相同模式的csv,如下所示:
JavaRDD<String> dataFromCSV = javaSparkContext.textFile(fileURL);
//The I create a JavaRDD of the POJO type
JavaRDD<StowageTable> dataToPOJO = dataFromCSV.map((Function<String, StowageTable) line -> {
String[] fields = line.split(",");
StowageTable st = createNewStowageTable(fields);
return st;
});
//converting the RDD to DataFrame
DataFrame stowageTableDF = sqlContext.createDataFrame(dataToPOJO, StowageTable.class);
//call jdbc persister
persistToTable(stowageTableDF);
我的persistToTable(DataFrame df)
方法如下:
private void persistToTable(DataFrame df) {
Class.forName("")//driver here
//skipping a few lines for brevity
df.write().mode(SaveMode.Append).jdbc(url, table, connectionProperties);
}
我在这里找到了一些解决方案:Spark DataFrame write to JDBC - Can't get JDBC type for array<array<int>>和java.lang.IllegalArgumentException: Can't get JDBC type for array<string>但找不到任何解决日期时间数据类型问题的方法。请建议我一些解决方案。我在火花1.6.3。
由于我还没有找到任何答案,并在此期间找到了自己的解决方案,所以这里是基本的想法。如果数据库的数据类型为Timestamp,则必须在对象的POJO中使用Timestamp,然后将该Timestamp转换为spark的structtype。