Error while writing dataframe with all columns cast to string

[Sandy247]

We are trying to write a dataframe which has all columns cast to StringType(). It was working for us previously, but now we get:

org.apache.spark.SparkException: Job aborted due to stage failure: Task 10 in stage 352.0 failed 4 times, most recent failure: Lost task 10.3 in stage 352.0 (TID 23759, 10.139.64.13, executor 29): java.lang.ClassCastException: java.lang.Long cannot be cast to org.apache.spark.unsafe.types.UTF8String.

This is the entire stacktrace:
**Py4JJavaError: An error occurred while calling o1074.save.
: org.apache.spark.SparkException: Job aborted due to stage failure: Task 10 in stage 352.0 failed 4 times, most recent failure: Lost task 10.3 in stage 352.0 (TID 23759, 10.139.64.13, executor 29): java.lang.ClassCastException: java.lang.Long cannot be cast to org.apache.spark.unsafe.types.UTF8String
at org.apache.spark.sql.catalyst.expressions.BaseGenericInternalRow$class.getUTF8String(rows.scala:46)
at org.apache.spark.sql.catalyst.expressions.GenericInternalRow.getUTF8String(rows.scala:195)
at org.apache.spark.sql.catalyst.expressions.GeneratedClass$GeneratedIteratorForCodegenStage1.processNext(Unknown Source)
at org.apache.spark.sql.execution.BufferedRowIterator.hasNext(BufferedRowIterator.java:43)
at org.apache.spark.sql.execution.WholeStageCodegenExec$$anonfun$13$$anon$1.hasNext(WholeStageCodegenExec.scala:640)
at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:409)
at org.apache.spark.shuffle.sort.BypassMergeSortShuffleWriter.write(BypassMergeSortShuffleWriter.java:125)
at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMapTask.scala:99)
at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMapTask.scala:55)
at org.apache.spark.scheduler.Task.doRunTask(Task.scala:140)
at org.apache.spark.scheduler.Task.run(Task.scala:113)
at org.apache.spark.executor.Executor$TaskRunner$$anonfun$17.apply(Executor.scala:606)
at org.apache.spark.util.Utils$.tryWithSafeFinally(Utils.scala:1541)
at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:612)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)

Driver stacktrace:
at org.apache.spark.scheduler.DAGScheduler.org$apache$spark$scheduler$DAGScheduler$$failJobAndIndependentStages(DAGScheduler.scala:2362)
at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:2350)
at org.apache.spark.scheduler.DAGScheduler$$anonfun$abortStage$1.apply(DAGScheduler.scala:2349)
at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:59)
at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:48)
at org.apache.spark.scheduler.DAGScheduler.abortStage(DAGScheduler.scala:2349)
at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:1102)
at org.apache.spark.scheduler.DAGScheduler$$anonfun$handleTaskSetFailed$1.apply(DAGScheduler.scala:1102)
at scala.Option.foreach(Option.scala:257)
at org.apache.spark.scheduler.DAGScheduler.handleTaskSetFailed(DAGScheduler.scala:1102)
at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.doOnReceive(DAGScheduler.scala:2582)
at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:2529)
at org.apache.spark.scheduler.DAGSchedulerEventProcessLoop.onReceive(DAGScheduler.scala:2517)
at org.apache.spark.util.EventLoop$$anon$1.run(EventLoop.scala:49)
at org.apache.spark.scheduler.DAGScheduler.runJob(DAGScheduler.scala:897)
at org.apache.spark.SparkContext.runJob(SparkContext.scala:2280)
at org.apache.spark.SparkContext.runJob(SparkContext.scala:2302)
at org.apache.spark.SparkContext.runJob(SparkContext.scala:2321)
at org.apache.spark.SparkContext.runJob(SparkContext.scala:2346)
at org.apache.spark.rdd.RDD$$anonfun$collect$1.apply(RDD.scala:997)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112)
at org.apache.spark.rdd.RDD.withScope(RDD.scala:392)
at org.apache.spark.rdd.RDD.collect(RDD.scala:996)
at com.microsoft.azure.cosmosdb.spark.CosmosDBSpark$.save(CosmosDBSpark.scala:197)
at com.microsoft.azure.cosmosdb.spark.CosmosDBSpark$.save(CosmosDBSpark.scala:540)
at com.microsoft.azure.cosmosdb.spark.DefaultSource.createRelation(DefaultSource.scala:69)
at org.apache.spark.sql.execution.datasources.SaveIntoDataSourceCommand.run(SaveIntoDataSourceCommand.scala:45)
at org.apache.spark.sql.execution.command.ExecutedCommandExec.sideEffectResult$lzycompute(commands.scala:70)
at org.apache.spark.sql.execution.command.ExecutedCommandExec.sideEffectResult(commands.scala:68)
at org.apache.spark.sql.execution.command.ExecutedCommandExec.doExecute(commands.scala:86)
at org.apache.spark.sql.execution.SparkPlan$$anonfun$execute$1.apply(SparkPlan.scala:150)
at org.apache.spark.sql.execution.SparkPlan$$anonfun$execute$1.apply(SparkPlan.scala:138)
at org.apache.spark.sql.execution.SparkPlan$$anonfun$executeQuery$5.apply(SparkPlan.scala:191)
at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151)
at org.apache.spark.sql.execution.SparkPlan.executeQuery(SparkPlan.scala:187)
at org.apache.spark.sql.execution.SparkPlan.execute(SparkPlan.scala:138)
at org.apache.spark.sql.execution.QueryExecution.toRdd$lzycompute(QueryExecution.scala:117)
at org.apache.spark.sql.execution.QueryExecution.toRdd(QueryExecution.scala:115)
at org.apache.spark.sql.DataFrameWriter$$anonfun$runCommand$1.apply(DataFrameWriter.scala:712)
at org.apache.spark.sql.DataFrameWriter$$anonfun$runCommand$1.apply(DataFrameWriter.scala:712)
at org.apache.spark.sql.execution.SQLExecution$$anonfun$withCustomExecutionEnv$1$$anonfun$apply$1.apply(SQLExecution.scala:112)
at org.apache.spark.sql.execution.SQLExecution$.withSQLConfPropagated(SQLExecution.scala:233)
at org.apache.spark.sql.execution.SQLExecution$$anonfun$withCustomExecutionEnv$1.apply(SQLExecution.scala:98)
at org.apache.spark.sql.SparkSession.withActive(SparkSession.scala:835)
at org.apache.spark.sql.execution.SQLExecution$.withCustomExecutionEnv(SQLExecution.scala:74)
at org.apache.spark.sql.execution.SQLExecution$.withNewExecutionId(SQLExecution.scala:185)
at org.apache.spark.sql.DataFrameWriter.runCommand(DataFrameWriter.scala:712)
at org.apache.spark.sql.DataFrameWriter.saveToV1Source(DataFrameWriter.scala:308)
at org.apache.spark.sql.DataFrameWriter.save(DataFrameWriter.scala:294)
at sun.reflect.GeneratedMethodAccessor714.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:380)
at py4j.Gateway.invoke(Gateway.java:295)
at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
at py4j.commands.CallCommand.execute(CallCommand.java:79)
at py4j.GatewayConnection.run(GatewayConnection.java:251)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.ClassCastException: java.lang.Long cannot be cast to org.apache.spark.unsafe.types.UTF8String
at org.apache.spark.sql.catalyst.expressions.BaseGenericInternalRow$class.getUTF8String(rows.scala:46)
at org.apache.spark.sql.catalyst.expressions.GenericInternalRow.getUTF8String(rows.scala:195)
at org.apache.spark.sql.catalyst.expressions.GeneratedClass$GeneratedIteratorForCodegenStage1.processNext(Unknown Source)
at org.apache.spark.sql.execution.BufferedRowIterator.hasNext(BufferedRowIterator.java:43)
at org.apache.spark.sql.execution.WholeStageCodegenExec$$anonfun$13$$anon$1.hasNext(WholeStageCodegenExec.scala:640)
at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:409)
at org.apache.spark.shuffle.sort.BypassMergeSortShuffleWriter.write(BypassMergeSortShuffleWriter.java:125)
at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMapTask.scala:99)
at org.apache.spark.scheduler.ShuffleMapTask.runTask(ShuffleMapTask.scala:55)
at org.apache.spark.scheduler.Task.doRunTask(Task.scala:140)
at org.apache.spark.scheduler.Task.run(Task.scala:113)
at org.apache.spark.executor.Executor$TaskRunner$$anonfun$17.apply(Executor.scala:606)
at org.apache.spark.util.Utils$.tryWithSafeFinally(Utils.scala:1541)**

Any help on this would be appreciated. Thanks!

[Sandy247]

Anyone else facing this issue? We get this intermittently and spark throws the above error or a ClassCastException. The same dataframe works on a few retries and cosmos is not hitting throughput limits. Is this an issue with the connector?

[absognety]

@southpolesteve @zfoster please look into this issue and suggest us the appropriate workaround, we are using databricks notebook for writing our spark workloads.
relevant issue found:
#348