[SPARK-16839] CleanupAliases may leave redundant aliases at end of analysis state

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.6.1, 2.0.0
• Fix Version/s: 2.1.0
• Component/s: SQL
• Labels: alias analysis analyzers sql struct
• Assignee: Eyal Farago
• Reporter: Eyal Farago
• Shepherd: Wenchen Fan
• Created: 01/Aug/16 21:46
• Updated: 01/Nov/16 16:48
• Resolved: 01/Nov/16 16:13

Description

SPARK-9634 SPARK-9323 [SQL] introduced CleanupReferences which removes unnecessary Aliases while keeping required ones such as top level Projection and struct attributes. this mechanism is implemented by maintaining a boolean flag during a top-down expression transformation, I found a case where this mechanism leaves redundant aliases in the tree (within a right sibling of a create_struct node).

Issue Links

• links to: [Github] Pull Request #14444 (eyalfa)
• links to: [Github] Pull Request #15718 (hvanhovell)