[SPARK-22036] BigDecimal multiplication sometimes returns null

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.2.0
• Fix Version/s: 2.3.0
• Component/s: SQL
• Assignee: Marco Gaido
• Reporter: Olivier Blanvillain
• Created: 16/Sep/17 11:12
• Updated: 20/Sep/18 23:40
• Resolved: 18/Jan/18 13:30

Description

The multiplication of two BigDecimal numbers sometimes returns null. Here is a minimal reproduction:

object Main extends App {
  import org.apache.spark.{SparkConf, SparkContext}
  import org.apache.spark.sql.SparkSession
  import spark.implicits._
  val conf = new SparkConf().setMaster("local[*]").setAppName("REPL").set("spark.ui.enabled", "false")
  val spark = SparkSession.builder().config(conf).appName("REPL").getOrCreate()
  implicit val sqlContext = spark.sqlContext

  case class X2(a: BigDecimal, b: BigDecimal)
  val ds = sqlContext.createDataset(List(X2(BigDecimal(-0.1267333984375), BigDecimal(-1000.1))))
  val result = ds.select(ds("a") * ds("b")).collect.head
  println(result) // [null]
}

Issue Links

• is duplicated by: SPARK-24606 Decimals multiplication and division may be null due to the result precision overflow
• is related to: SPARK-23179 Support option to throw exception if overflow occurs during Decimal arithmetic
• relates to: HIVE-15331 Decimal multiplication with high precision/scale often returns NULL
• links to: [Github] Pull Request #20023 (mgaido91)
• links to: [Github] Pull Request #20498 (wangyum)
• links to: [Github] Pull Request #22494 (cloud-fan)