[SPARK-30764] Improve the readability of EXPLAIN FORMATTED style

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.1.0
• Fix Version/s: 3.0.0
• Component/s: SQL
• Assignee: Xin Wu
• Reporter: Xin Wu
• Created: 09/Feb/20 12:51
• Updated: 18/Apr/20 18:33
• Resolved: 21/Feb/20 15:51

Description

The style of EXPLAIN FORMATTED output needs to be improved. We’ve already got some observations/ideas in
https://github.com/apache/spark/pull/27368#discussion_r376694496. 
 
TODOs:
1.Using comma as the separator is not clear, especially commas are used inside the expressions too.
2.Show the column counts first? For example, `Results [4]: …`
3.Currently the attribute names are automatically generated, this need to refined.
4.Add arguments field in common implications as EXPLAIN FORMATTED did in QueryPlan
...

Issue Links

• links to: GitHub Pull Request #27509