[GitHub] [spark] maropu commented on a change in pull request #28050: [MINOR][DOC] Refine comments of QueryPlan regarding subquery

[GitBox <gi...@apache.org>]

maropu commented on a change in pull request #28050: [MINOR][DOC] Refine comments of QueryPlan regarding subquery
URL: https://github.com/apache/spark/pull/28050#discussion_r399215147
 
 

 ##########
 File path: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/plans/QueryPlan.scala
 ##########
 @@ -23,6 +23,14 @@ import org.apache.spark.sql.catalyst.trees.{CurrentOrigin, TreeNode, TreeNodeTag
 import org.apache.spark.sql.internal.SQLConf
 import org.apache.spark.sql.types.{DataType, StructType}
 
+/**
+ * An abstraction of the Spark SQL query plan tree, which can be logical or physical. This class
+ * defines some basic properties of a query plan node, as well as some new transform APIs to
+ * transform the expressions of the plan node.
+ *
+ * Note that, the tree traverse APIs like `transform`, `foreach`, `collect`, etc. that are
+ * inherited from `TreeNode`, do not traverse into query plans inside subqueries.
 
 Review comment:
   well written. nit: How about adding the example here of the description, `QueryPlan -> Expression (PlanExpression) -> QueryPlan`?

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
users@infra.apache.org


With regards,
Apache Git Services

---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscribe@spark.apache.org
For additional commands, e-mail: reviews-help@spark.apache.org