Github user yhuai commented on a diff in the pull request:
https://github.com/apache/spark/pull/7773#discussion_r36047734
--- Diff:
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/physical/partitioning.scala
---
@@ -86,8 +87,12 @@ sealed trait Partitioning {
*/
def satisfies(required: Distribution): Boolean
- /** Returns the expressions that are used to key the partitioning. */
- def keyExpressions: Seq[Expression]
+ /**
+ * Returns true iff we can say that the partitioning scheme of this
[[Partitioning]]
+ * guarantees the same partitioning scheme described by `other`.
+ */
+ // TODO: Add an example once we have the `nullSafe` concept.
+ def guarantees(other: Partitioning): Boolean
--- End diff --
yeah, makes sense. Then, `semanticEqual` is not a good name because once we
have the concept of `nullSafe`. This method will not have the `commutative`
property because `nullSafe` hash partitioning can be treated as `nullUnsafe`
hash partitioning.
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at [email protected] or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
