[IMPALA-10977] Make zipping unnest work with absolute paths

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: Impala 4.1.0
• Component/s: Frontend
• Labels: complextype
• Epic Link: Fix complex type related issues
• Epic Color: ghx-label-9
• Assignee: Unassigned
• Reporter: Gabor Kaszab
• Created: 20/Oct/21 12:32
• Updated: 20/Oct/21 12:32

Description

IMPALA-10920 introduced zipping unnest that has the following syntax:

SELECT arr1.item, arr2.item FROM tbl t, UNNEST(t.arr1, t.arr2)

However, If the arrays are given with absolute path then the query doesn't work:

SELECT arr1.item, arr2.item FROM UNNEST(tbl.arr1, tbl.arr2)

The reason partly is because in SingleNodePlanner.createTableRefNode() the UNNEST node is only created when relative path is provided. As a result the memory layout for the tuples related to the unnest won't be computed and a check will fail.
But even if we create an UNNEST node even for absolute paths the plan tree will be wrong as there won't be any SUBPLAN and SCAN nodes, so in this case it should be handled separately to also add that part into the tree not just the UNNEST node.

Issue Links

• depends upon: IMPALA-10920 UNNEST function for arrays in the select list