洗牌数据透视PySpark数据帧行引发NullPointedException
假设下一个PySpark数据帧:洗牌数据透视PySpark数据帧行引发NullPointedException,pyspark,apache-spark-sql,Pyspark,Apache Spark Sql,假设下一个PySpark数据帧: +-------+----+---+---+----+ |user_id|type| d1| d2| d3| +-------+----+---+---+----+ | c1| A|3.4|0.4| 3.5| | c1| B|9.6|0.0| 0.0| | c1| A|2.8|0.4| 0.3| | c1| B|5.4|0.2|0.11| | c2| A|0.0|9.7| 0.3| | c2|
+-------+----+---+---+----+
|user_id|type| d1| d2| d3|
+-------+----+---+---+----+
| c1| A|3.4|0.4| 3.5|
| c1| B|9.6|0.0| 0.0|
| c1| A|2.8|0.4| 0.3|
| c1| B|5.4|0.2|0.11|
| c2| A|0.0|9.7| 0.3|
| c2| B|9.6|8.6| 0.1|
| c2| A|7.3|9.1| 7.0|
| c2| B|0.7|6.4| 4.3|
+-------+----+---+---+----+
创建时使用:
df = sc.parallelize([
("c1", "A", 3.4, 0.4, 3.5),
("c1", "B", 9.6, 0.0, 0.0),
("c1", "A", 2.8, 0.4, 0.3),
("c1", "B", 5.4, 0.2, 0.11),
("c2", "A", 0.0, 9.7, 0.3),
("c2", "B", 9.6, 8.6, 0.1),
("c2", "A", 7.3, 9.1, 7.0),
("c2", "B", 0.7, 6.4, 4.3)
]).toDF(["user_id", "type", "d1", "d2", "d3"])
df.show()
然后,通过user\u id
旋转它以获得:
data_wide = df.groupBy('user_id')\
.pivot('type')\
.agg(*[f.sum(x).alias(x) for x in df.columns if x not in {"user_id", "type"}])
data_wide.show()
+-------+-----------------+------------------+----+------------------+----+------------------+
|user_id| A_d1| A_d2|A_d3| B_d1|B_d2| B_d3|
+-------+-----------------+------------------+----+------------------+----+------------------+
| c1|6.199999999999999| 0.8| 3.8| 15.0| 0.2| 0.11|
| c2| 7.3|18.799999999999997| 7.3|10.299999999999999|15.0|4.3999999999999995|
+-------+-----------------+------------------+----+------------------+----+------------------+
现在,我想将其行顺序随机化:
data_wide = data_wide.orderBy(f.rand())
data_wide.show()
但最后一步抛出一个NullPointedException
:
Py4JJavaError: An error occurred while calling o101.showString.
: org.apache.spark.SparkException: Job aborted due to stage failure: Task 161 in stage 27.0 failed 20 times, most recent failure: Lost task 161.19 in stage 27.0 (TID 1300, 192.168.192.57, executor 1): java.lang.NullPointerException
at org.apache.spark.sql.catalyst.expressions.GeneratedClass$SpecificUnsafeProjection.apply_3$(Unknown Source)
at org.apache.spark.sql.catalyst.expressions.GeneratedClass$SpecificUnsafeProjection.apply(Unknown Source)
at org.apache.spark.sql.execution.aggregate.AggregationIterator$$anonfun$generateResultProjection$1.apply(AggregationIterator.scala:232)
但是,如果在orderBy(f.rand())
步骤之前缓存了宽df,则最后一步可以正常工作:
data_wide.cache()
data_wide = data_wide.orderBy(f.rand())
data_wide.show()
+-------+-----------------+------------------+----+------------------+----+------------------+
|user_id| A_d1| A_d2|A_d3| B_d1|B_d2| B_d3|
+-------+-----------------+------------------+----+------------------+----+------------------+
| c2| 7.3|18.799999999999997| 7.3|10.299999999999999|15.0|4.3999999999999995|
| c1|6.199999999999999| 0.8| 3.8| 15.0| 0.2| 0.11|
+-------+-----------------+------------------+----+------------------+----+------------------+
这里有什么问题?看起来,在orderBy
步骤中,pivot没有生效,也没有正确地计划执行,但我不知道实际的问题是什么。有什么想法吗
Spark版本是2.1.0,python版本是3.5.2
提前感谢您这在2.3.1版上对我有效,无需缓存。。。您使用的python和pyspark的版本是什么?@coldspeed对不起,spark的版本是2.1.0和Python3.5.2。这似乎是一个版本问题。我已经编辑了这个问题,谢谢。一个简单的更新能帮你解决吗?在spark 2.3.0中对我有效是的!一个简单的更新修复它,谢谢