[IMPALA-10356] Analyzed query in explain plan is not quite right for insert with values clause

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Impala 4.0.0
• Fix Version/s: Impala 4.2.0
• Component/s: Frontend
• Labels: newbie ramp-up
• Target Version: Product Backlog
• Epic Color: ghx-label-1
• Assignee: Daniel Becker
• Reporter: Tim Armstrong
• Created: 24/Nov/20 18:37
• Updated: 12/Oct/22 23:07
• Resolved: 12/Oct/22 22:05

Description

In impala-shell:

create table double_tbl (d double) stored as textfile;
set explain_level=2;
explain insert into double_tbl values (-0.43149576573887316);

+----------------------------------------------------------------------------------+
| Explain String                                                                   |
+----------------------------------------------------------------------------------+
| Max Per-Host Resource Reservation: Memory=0B Threads=1                           |
| Per-Host Resource Estimates: Memory=10MB                                         |
| Codegen disabled by planner                                                      |
| Analyzed query: SELECT CAST(-0.43149576573887316 AS DECIMAL(17,17)) UNION SELECT |
| CAST(-0.43149576573887316 AS DECIMAL(17,17))                                     |
|                                                                                  |
| F00:PLAN FRAGMENT [UNPARTITIONED] hosts=1 instances=1                            |
| |  Per-Host Resources: mem-estimate=8B mem-reservation=0B thread-reservation=1   |
| WRITE TO HDFS [default.double_tbl, OVERWRITE=false]                              |
| |  partitions=1                                                                  |
| |  output exprs: CAST(-0.43149576573887316 AS DOUBLE)                            |
| |  mem-estimate=8B mem-reservation=0B thread-reservation=0                       |
| |                                                                                |
| 00:UNION                                                                         |
|    constant-operands=1                                                           |
|    mem-estimate=0B mem-reservation=0B thread-reservation=0                       |
|    tuple-ids=0 row-size=8B cardinality=1                                         |
|    in pipelines: <none>                                                          |
+----------------------------------------------------------------------------------+

The analyzed query does not make sense. We should investigate and fix it.