You are viewing a plain text version of this content. The canonical link for it is here.
Posted to reviews@spark.apache.org by rdblue <gi...@git.apache.org> on 2018/08/01 02:42:40 UTC
[GitHub] spark pull request #21911: [SPARK-24940][SQL] Coalesce Hint for SQL Queries
Github user rdblue commented on a diff in the pull request:
https://github.com/apache/spark/pull/21911#discussion_r206740826
--- Diff: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/ResolveHints.scala ---
@@ -102,6 +104,39 @@ object ResolveHints {
}
}
+ /**
+ * For coalesce hint, we accept "COALESCE" and "REPARTITION".
+ * Its parameters include a partition number and an optional boolean to indicate
+ * whether shuffle is allowed.
+ */
+ class ResolveCoalesceHints(conf: SQLConf) extends Rule[LogicalPlan] {
+ private val COALESCE_HINT_NAMES = Set("COALESCE", "REPARTITION")
+
+ private def applyCoalesceHint(
+ plan: LogicalPlan,
+ numPartitions: Int,
+ shuffle: Boolean): LogicalPlan = {
+ Repartition(numPartitions, shuffle, plan)
+ }
+
+ def apply(plan: LogicalPlan): LogicalPlan = plan.resolveOperators {
+ case h: UnresolvedHint if COALESCE_HINT_NAMES.contains(h.name.toUpperCase(Locale.ROOT)) =>
+ h.parameters match {
+ case Seq(Literal(i, IntegerType)) =>
+ val defaultShuffle = h.name.toUpperCase(Locale.ROOT) match {
+ case "REPARTITION" => true
+ case _ => false
+ }
+ applyCoalesceHint(h.child, i.asInstanceOf[Int], defaultShuffle)
--- End diff --
Instead of casting, this should add the expected type to the pattern match.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscribe@spark.apache.org
For additional commands, e-mail: reviews-help@spark.apache.org