Do you know how I can check that? I googled a bit but couldn't find a clear
explanation about it. I also tried to use explain() but it doesn't really
help.
I still find unusual that I have this issue only for the equality operator
but not for the others.
Thank you,
F
On Wed, Apr 29, 2015 at 3:03 PM ayan guha <guha.a...@gmail.com> wrote:
> Looks like you DF is based on a MySQL DB using jdbc, and error is thrown
> from mySQL. Can you see what SQL is finally getting fired in MySQL? Spark
> is pushing down the predicate to mysql so its not a spark problem perse
>
> On Wed, Apr 29, 2015 at 9:56 PM, Francesco Bigarella <
> francesco.bigare...@gmail.com> wrote:
>
>> Hi all,
>>
>> I was testing the DataFrame filter functionality and I found what I think
>> is a strange behaviour.
>> My dataframe testDF, obtained loading aMySQL table via jdbc, has the
>> following schema:
>> root
>> | -- id: long (nullable = false)
>> | -- title: string (nullable = true)
>> | -- value: string (nullable = false)
>> | -- status: string (nullable = false)
>>
>> What I want to do is filter my dataset to obtain all rows that have a
>> status = "new".
>>
>> scala> testDF.filter(testDF("id") === 1234).first()
>> works fine (also with the integer value within double quotes), however if
>> I try to use the same statement to filter on the status column (also with
>> changes in the syntax - see below), suddenly the program breaks.
>>
>> Any of the following
>> scala> testDF.filter(testDF("status") === "new")
>> scala> testDF.filter("status = 'new'")
>> scala> testDF.filter($"status" === "new")
>>
>> generates the error:
>>
>> INFO scheduler.DAGScheduler: Job 3 failed: runJob at
>> SparkPlan.scala:121, took 0.277907 s
>>
>> org.apache.spark.SparkException: Job aborted due to stage failure: Task 0
>> in stage 3.0 failed 4 times, most recent failure: Lost task 0.3 in stage
>> 3.0 (TID 12, <node name>):
>> com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column
>> 'new' in 'where clause'
>>
>> at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
>> at
>> sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
>> at
>> sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
>> at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
>> at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
>> at com.mysql.jdbc.Util.getInstance(Util.java:386)
>> at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1052)
>> at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3597)
>> at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3529)
>> at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1990)
>> at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2151)
>> at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2625)
>> at
>> com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2119)
>> at
>> com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2283)
>> at org.apache.spark.sql.jdbc.JDBCRDD$anon$1.<init>(JDBCRDD.scala:328)
>> at org.apache.spark.sql.jdbc.JDBCRDD.compute(JDBCRDD.scala:309)
>> at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:277)
>> at org.apache.spark.rdd.RDD.iterator(RDD.scala:244)
>> at
>> org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:35)
>> at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:277)
>> at org.apache.spark.rdd.RDD.iterator(RDD.scala:244
>> at
>> org.apache.spark.rdd.MapPartitionsRDD.compute(MapPartitionsRDD.scala:35)
>> at org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:277)
>> at org.apache.spark.rdd.RDD.iterator(RDD.scala:244)
>> at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:61)
>> at org.apache.spark.scheduler.Task.run(Task.scala:64)
>> at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:203)
>> at
>> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
>> at
>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
>> at java.lang.Thread.run(Thread.java:745)
>>
>> Does filter work only on columns of the integer type? What is the exact
>> behaviour of the filter function and what is the best way to handle the
>> query I am trying to execute?
>>
>> Thank you,
>> Francesco
>>
>>
>
>
> --
> Best Regards,
> Ayan Guha
>
