[SPARK-20938] explain() for datasources implementing CatalystScan does not show pushed predicates correctly

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Incomplete
• Affects Version/s: 2.2.0
• Component/s: SQL
• Labels: bulk-closed
• Assignee: Unassigned
• Reporter: Hyukjin Kwon
• Created: 31/May/17 09:50
• Updated: 12/Dec/22 17:51
• Resolved: 21/May/19 04:16

Description

Actual pushed-down catalyst predicate expressions look not being represented correctly (but only sources filters) when we use a datasource implementing CatalystScan. For example, the below case

df.filter("cast(a as string) == '1' and a < 3").explain()

prints the plan as below:

== Physical Plan ==
*Filter (cast(a#0L as string) = 1)
+- *Scan SimpleCatalystScan(0,10) [a#0L] PushedFilters: [*LessThan(a,3)], ReadSchema: struct<a:bigint>

Actual predicates via buildScan(requiredColumns: Seq[Attribute], filters: Seq[Expression]) are as below:

println(filters.mkString("[", ", ", "]"))

[(cast(a#0L as string) = 1), (a#0L < 3)]

Issue Links

• links to: [Github] Pull Request #18160 (HyukjinKwon)