向数据框添加新列的问题-Spark/Scala [英] Problems with adding a new column to a dataframe - spark/scala
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问题描述
我是火花/scala的新手.我正在尝试从配置单元表中读取一些数据到spark数据框，然后根据某些条件添加一列.这是我的代码:
I am new to spark/scala. I am trying to read some data from a hive table to a spark dataframe and then add a column based on some condition. Here is my code:
val DF = hiveContext.sql("select * from (select * from test_table where partition_date='2017-11-22') a JOIN (select max(id) as bid from test_table where partition_date='2017-11-22' group by at_id) b ON a.id=b.bid")
def dateDiff(partition_date: org.apache.spark.sql.Column, item_due_date: org.apache.spark.sql.Column): Long ={
ChronoUnit.DAYS.between(LocalDate.parse(partition_date.toString()), LocalDate.parse(item_due_date.toString))
}
val finalDF = DF.withColumn("status",
when(col("past_due").equalTo(1) && !(col("item_due_date").equalTo(null) || col("item_due_date").equalTo("NULL") || col("item_due_date").equalTo("null")) && (dateDiff(col("partition_date"),col("item_due_date")) < 0) && !(col("item_decision").equalTo(null) || col("item_decision").equalTo("NULL") || col("item_decision").equalTo("null")), "approved")
.when(col("past_due").equalTo(1) && !(col("item_due_date").equalTo(null) || col("item_due_date").equalTo("NULL") || col("item_due_date").equalTo("null")) && (dateDiff(col("partition_date"),col("item_due_date")) < 0) && (col("item_decision").equalTo(null) || col("item_decision").equalTo("NULL") || col("item_decision").equalTo("null")), "pending")
.when(col("past_due").equalTo(1) && !(col("item_due_date").equalTo(null) || col("item_due_date").equalTo("NULL") || col("item_due_date").equalTo("null")) && (dateDiff(col("partition_date"),col("item_due_date")) >= 0), "expired")
.otherwise("null"))
dateDiff是用于计算partition_date和item_due_date(它们是DF中的列)之间的差的函数.我正在尝试通过使用when和otherwise向DF添加新列，该列使用dateDiff获取日期之间的差额.
dateDiff is a function that calculates the difference between partition_date and item_due_date, which are columns in DF. I am trying to add a new column to DF by using when and otherwise which uses the dateDiff to get the difference between dates.
现在，当我运行上面的代码时，出现以下错误:org.threeten.bp.format.DateTimeParseException: Text 'partition_date' could not be parsed at index 0
Now, when I run the above code, I get the following error: org.threeten.bp.format.DateTimeParseException: Text 'partition_date' could not be parsed at index 0
我相信列partition_date的值不会转换为要解析为日期的字符串.这是怎么回事吗?如果是，如何将列值转换为字符串?
I believe the value of the column partition_date is not being converted to a String to be parsed as a date. Is this what's happening? If yes, how do I cast the column value to a String ?
下面是DF中我正在使用的列的模式:
Below is the schema of the columns I am using from the DF :
|-- item_due_date: string (nullable = true)
|-- past_due: integer (nullable = true)
|-- item_decision: string (nullable = true)
|-- partition_date: string (nullable = true)
我在DF中使用的列的数据样本:
A data sample of the columns I am using from the DF :
+--------+-------------+-------------+--------------+
|past_due|item_due_date|item_decision|partition_date|
+--------+-------------+-------------+--------------+
| 1| 0001-01-14| null| 2017-11-22|
| 1| 0001-01-14| Mitigate| 2017-11-22|
| 1| 0001-01-14| Mitigate| 2017-11-22|
| 1| 0001-01-14| Mitigate| 2017-11-22|
| 0| 2018-03-18| null| 2017-11-22|
| 1| 2016-11-30| null| 2017-11-22|
+--------+-------------+-------------+--------------+
我还尝试使用自定义UDF:
I also tried using a custom UDF:
def status(past_due: Int, item_decision: String, maxPartitionDate: String, item_due_date: String): String = {
if (past_due == 1 && item_due_date != "NULL") {
if (ChronoUnit.DAYS.between(LocalDate.parse(maxPartitionDate.trim), LocalDate.parse(item_due_date.trim)) < 0) {
if (item_decision != "NULL") "pending"
else "approved"
} else "expired"
} else "NULL"
}
val statusUDF = sqlContext.udf.register("statusUDF", status _)
val DF2 = DF.withColumn("status", statusUDF(DF("past_due"),DF("item_decision"),DF("partition_date"),DF("item_due_date")))
DF2.show()
并且每次都会在DF2.show语句上引发以下错误:
And it throws the following error at the DF2.show statement, everytime:
Container exited with a non-zero exit code 50
Driver stacktrace:
at org.apache.spark.scheduler.DAGScheduler.org$apache$spark$scheduler$DAGScheduler$$failJobAndIndependentStages(DAGScheduler.scala:1433)
at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:1421)
at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:1420)
at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:59)
at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:47)
at org.apache.spark.scheduler.DAGScheduler.abortStage(DAGScheduler.scala:1420)
at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:799)
at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:799)
at scala.Option.foreach(Option.scala:236)
at org.apache.spark.scheduler.DAGScheduler.handleTaskSetFailed(DAGScheduler.scala:799)
at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.doOnReceive(DAGScheduler.scala:1644)
at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:1603)
at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:1592)
at org.apache.spark.util.EventLoop$$anon$1.run(EventLoop.scala:48)
at org.apache.spark.scheduler.DAGScheduler.runJob(DAGScheduler.scala:620)
at org.apache.spark.SparkContext.runJob(SparkContext.scala:1844)
at org.apache.spark.SparkContext.runJob(SparkContext.scala:1857)
at org.apache.spark.SparkContext.runJob(SparkContext.scala:1870)
at org.apache.spark.sql.execution.SparkPlan.executeTake(SparkPlan.scala:212)
at org.apache.spark.sql.execution.Limit.executeCollect(basicOperators.scala:165)
at org.apache.spark.sql.execution.SparkPlan.executeCollectPublic(SparkPlan.scala:174)
at org.apache.spark.sql.DataFrame$$anonfun$org$apache$spark$sql$DataFrame$$execute$1$1.apply(DataFrame.scala:1499)
at org.apache.spark.sql.DataFrame$$anonfun$org$apache$spark$sql$DataFrame$$execute$1$1.apply(DataFrame.scala:1499)
at org.apache.spark.sql.execution.SQLExecution$.withNewExecutionId(SQLExecution.scala:53)
at org.apache.spark.sql.DataFrame.withNewExecutionId(DataFrame.scala:2086)
at org.apache.spark.sql.DataFrame.org$apache$spark$sql$DataFrame$$execute$1(DataFrame.scala:1498)
at org.apache.spark.sql.DataFrame.org$apache$spark$sql$DataFrame$$collect(DataFrame.scala:1505)
at org.apache.spark.sql.DataFrame$$anonfun$head$1.apply(DataFrame.scala:1375)
at org.apache.spark.sql.DataFrame$$anonfun$head$1.apply(DataFrame.scala:1374)
at org.apache.spark.sql.DataFrame.withCallback(DataFrame.scala:2099)
at org.apache.spark.sql.DataFrame.head(DataFrame.scala:1374)
at org.apache.spark.sql.DataFrame.take(DataFrame.scala:1456)
at org.apache.spark.sql.DataFrame.showString(DataFrame.scala:170)
at org.apache.spark.sql.DataFrame.show(DataFrame.scala:350)
at org.apache.spark.sql.DataFrame.show(DataFrame.scala:311)
at org.apache.spark.sql.DataFrame.show(DataFrame.scala:319)
at driver$.main(driver.scala:109)
at driver.main(driver.scala)
任何帮助将不胜感激.谢谢！
Any help would be appreciated. Thank you!
推荐答案
您可以简单地使用datediff内置函数来检查两列之间的天数差异.您无需编写函数或udf函数.而且当功能也比您的功能修改时
You can simply use datediff inbuilt function to check for the days difference between two columns. you don't need to write your function or udf function. And when function is also modified than yours
import org.apache.spark.sql.functions._
val finalDF = DF.withColumn("status",
when(col("past_due").equalTo(1) && col("item_due_date").isNotNull && !(lower(col("item_due_date")).equalTo("null")) && (datediff(col("partition_date"),col("item_due_date")) < 0) && col("item_decision").isNotNull && !(lower(col("item_decision")).equalTo("null")), "approved")
.otherwise(when(col("past_due").equalTo(1) && col("item_due_date").isNotNull && !(lower(col("item_due_date")).equalTo("null")) && (datediff(col("partition_date"),col("item_due_date")) < 0) && (col("item_decision").isNull || lower(col("item_decision")).equalTo("null")), "pending")
.otherwise(when(col("past_due").equalTo(1) && col("item_due_date").isNotNull && !(lower(col("item_due_date")).equalTo("null")) && (datediff(col("partition_date"),col("item_due_date")) >= 0), "expired")
.otherwise("null"))))
此逻辑将转换dataframe
+--------+-------------+-------------+--------------+
|past_due|item_due_date|item_decision|partition_date|
+--------+-------------+-------------+--------------+
|1 |2017-12-14 |null |2017-11-22 |
|1 |2017-12-14 |Mitigate |2017-11-22 |
|1 |0001-01-14 |Mitigate |2017-11-22 |
|1 |0001-01-14 |Mitigate |2017-11-22 |
|0 |2018-03-18 |null |2017-11-22 |
|1 |2016-11-30 |null |2017-11-22 |
+--------+-------------+-------------+--------------+
加上status列为
+--------+-------------+-------------+--------------+--------+
|past_due|item_due_date|item_decision|partition_date|status |
+--------+-------------+-------------+--------------+--------+
|1 |2017-12-14 |null |2017-11-22 |pending |
|1 |2017-12-14 |Mitigate |2017-11-22 |approved|
|1 |0001-01-14 |Mitigate |2017-11-22 |expired |
|1 |0001-01-14 |Mitigate |2017-11-22 |expired |
|0 |2018-03-18 |null |2017-11-22 |null |
|1 |2016-11-30 |null |2017-11-22 |expired |
+--------+-------------+-------------+--------------+--------+
我希望答案会有所帮助
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