scala Questions
6
Solved
I'm using official JDBC driver for PostgreSQL, but I'm stuck with the following issues:
No support for PostgreSQL-ish data structures such as UUIDs.
Common JDBC weirdness, such as:
No function t...
Taxis asked 4/2, 2011 at 16:13
4
Solved
I have a json file:
{
"a": {
"b": 1
}
}
I am trying to read it:
val path = "D:/playground/input.json"
val df = spark.read.json(path)
df.show()
But getting an erro...
Aldredge asked 11/8, 2019 at 16:27
9
Solved
I have a List of Map[String, Double], and I'd like to merge their contents into a single Map[String, Double]. How should I do this in an idiomatic way? I imagine that I should be able to do this wi...
Cupola asked 11/8, 2009 at 20:30
4
Solved
Suppose I have an array column group_ids
+-------+----------+
|user_id|group_ids |
+-------+----------+
|1 |[5, 8] |
|3 |[1, 2, 3] |
|2 |[1, 4] |
+-------+----------+
Schema:
root
|-- user_id: in...
Fanfani asked 19/3, 2021 at 22:53
2
In the spark-shell (scala), we import,
org.apache.spark.sql.hive.thriftserver._
for starting Hive Thrift server programatically for a particular hive context as
HiveThriftServer2.startWithContext(h...
Sweptwing asked 14/4, 2016 at 16:32
4
Solved
I have a array of tuple like this:
val a = Array((1,2,3), (2,3,4))
I want to write a generic method for a method like below:
def sum2nd(aa: Array[(Int, Int, Int)]) = {
aa.map { a => a._2 }....
Depicture asked 29/1, 2016 at 18:17
4
I've already read the question and answers to What design decisions would favour Scala's Actors instead of JMS?.
Usually, we use messaging solutions which have existed for years already: either a ...
4
I want to use an external BOM to manage dependency versions for my project in SBT.
For example, the AWS Java SDK publishes a bill-of-materials artifact to their maven repository: https://mvnrepos...
2
Solved
I have a project that I host on GitHub and I use scala-steward to keep my plugins and dependencies up to date. This worked for a while and now it is turning out to be a nightmare to use such auto u...
15
Solved
What's the easiest way to debug Scala code managed by sbt using IntelliJ's built-in debugger? The documentation from "RunningSbt" from sbt's google code site lists commands for running the main cla...
Gerome asked 11/11, 2010 at 1:48
6
Assuming I have a (what I assume is mutable by default) Array[String]
How in Scala can I simply remove the nth element?
No simple method seems to be available.
Want Something like (I made this u...
Sydneysydnor asked 11/1, 2014 at 0:47
2
Solved
Assuming you have case classes like the following
case class Test1(a:String,b:Int,c:Char)
case class Test2(a:String,b:Int)
And you instantiate the classes with the following variables
val test...
Petrolatum asked 21/4, 2014 at 7:17
1
This simplified case is where my question happen at...
object Main extends IOApp{
def run(args:Seq[String]): IO[ExitCode]={
Task{...}
.to[IO]
.as(ExitCode.Success)
}
}
Another option is Await...
Trussell asked 15/2, 2020 at 6:50
2
My sbt project takes more than 15 minutes when I do
sbt clean compile
I am on a beefy machine on AWS. I am fairly certain its not a resource issue on cpu or internet bandwidth. Also, I have run...
5
Solved
I am using Slick 1.0.0 with play framework 2.1.0. I am getting the following error when I query my Users table. The value of LOGIN_ID is null in DB.
The query I am executing is:
val user = { for...
Nesta asked 31/3, 2013 at 16:58
5
Solved
For example:
scala> val l:List[String] = List("one", "two")
l: List[String] = List(one, two)
scala> l.contains(1) //wish this didn't compile
res11: Boolean = false
The various explanatio...
Prestigious asked 16/1, 2010 at 17:18
3
Solved
In my project, my external library is spark-assembly-1.3.1-hadoop2.6.0, if I press '.', the IDE inform me toDF(), but it inform me that can't resolve symbol toDF() when I code it in. I'm sorry I ca...
Bloat asked 30/6, 2015 at 16:42
2
Hi I try to run spark on my local laptop.
I created a mvn project in intelijidea and in my main class I have one line like bellow and when I try to run a project I got the error like below
val spa...
Maxim asked 2/11, 2021 at 17:8
2
Error Message - job failed with error message The output of the notebook is too large. Cause: rpc response (of 20972488 bytes) exceeds limit of 20971520 bytes
Details:
We are using databricks noteb...
Tippet asked 3/12, 2021 at 9:53
2
Solved
I have a Scala Spark application and want to invoke pySpark/python (pyspark_script.py) for further processing.
There are multiple resources to use Java/Scala code in Python but I am looking for sca...
Empale asked 12/8, 2021 at 19:27
21
I'm evaluating IntelliJ (13.0.2 133.696) and cannot get jUnit tests to run from within the IDE.
My project is a multi module gradle project and uses scala.
Test class is located under src/test/s...
Ardin asked 28/2, 2014 at 20:33
4
Solved
In Scala, suppose I have a case class like this:
case class Sample(myInt: Int, myString: String)
Is there a way for me to obtain a Seq[(String, Class[_])], or better yet, Seq[(String, Manifest)]...
Randa asked 8/6, 2011 at 17:0
12
Solved
Given the following Scala List:
val l = List(List("a1", "b1", "c1"), List("a2", "b2", "c2"), List("a3", "b3", "c3"))
How can I get:
List(("a1", "a2", "a3"), ("b1", "b2", "b3"), ("c1", "c2", "c3...
Redeem asked 2/11, 2009 at 23:49
1
Solved
I am getting the issue below:
java.lang.reflect.InaccessibleObjectException: Unable to make field protected transient int java.util.AbstractList.modCount accessible: module java.base does not "...
4
Solved
How can I set target JVM version in SBT?
In Maven (with maven-scala-plugin) it can be done as follows:
<plugin>
...
<configuration>
<scalaVersion>${scala.version}</scalaVers...
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