[
https://issues.apache.org/jira/browse/HIVE-28362?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17863667#comment-17863667
]
Shohei Okumiya commented on HIVE-28362:
---------------------------------------
I noticed VOID is not listed as an official type. It is not usually supported,
e.g., Iceberg.
"4.6.2 Null value" in part 1 says we can use the NULL literal only when the
type can be inferred. The first option, i.e. supporting VOID in both regular
CTAS and materialization, is unlikely to be a valid option.
"6.5" of Part 2 says NULL literal is acceptable as a part of <contextually
typed value specification>. The definition of "contextually typed" could be
controversial, but my NULL is apparently not in the valid context. There is a
room to infer types from the top-level SELECT in our real cases, but it is not
obvious that we can legally infer types of CTEs from the top-level expressions.
I am still considering the option, but I will the most likely void this ticket.
> Fail to materialize a CTE with VOID
> -----------------------------------
>
> Key: HIVE-28362
> URL: https://issues.apache.org/jira/browse/HIVE-28362
> Project: Hive
> Issue Type: Bug
> Components: Query Planning
> Affects Versions: 4.0.0
> Reporter: Shohei Okumiya
> Assignee: Shohei Okumiya
> Priority: Major
> Labels: pull-request-available
>
> CTE materialization fails when it includes a NULL literal.
> {code:java}
> set hive.optimize.cte.materialize.full.aggregate.only=false;
> set hive.optimize.cte.materialize.threshold=2;
> WITH x AS (SELECT null AS null_value)
> SELECT * FROM x UNION ALL SELECT * FROM x; {code}
> Error message.
> {code:java}
> org.apache.hadoop.hive.ql.parse.SemanticException: CREATE-TABLE-AS-SELECT
> creates a VOID type, please use CAST to specify the type, near field:
> null_value
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.deriveFileSinkColTypes(SemanticAnalyzer.java:8344)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.deriveFileSinkColTypes(SemanticAnalyzer.java:8303)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.genFileSinkPlan(SemanticAnalyzer.java:7846)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.genPostGroupByBodyPlan(SemanticAnalyzer.java:11598)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.genBodyPlan(SemanticAnalyzer.java:11461)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.genPlan(SemanticAnalyzer.java:12397)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.genPlan(SemanticAnalyzer.java:12263)
> at
> org.apache.hadoop.hive.ql.parse.CalcitePlanner.genOPTree(CalcitePlanner.java:638)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.analyzeInternal(SemanticAnalyzer.java:13136)
> at
> org.apache.hadoop.hive.ql.parse.CalcitePlanner.analyzeInternal(CalcitePlanner.java:465)
> at
> org.apache.hadoop.hive.ql.parse.CalcitePlanner.materializeCTE(CalcitePlanner.java:1062)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.getMetaData(SemanticAnalyzer.java:2390)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.getMetaData(SemanticAnalyzer.java:2338)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.getMetaData(SemanticAnalyzer.java:2340)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.getMetaData(SemanticAnalyzer.java:2501)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.getMetaData(SemanticAnalyzer.java:2323)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.genResolvedParseTree(SemanticAnalyzer.java:12978)
> at
> org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.analyzeInternal(SemanticAnalyzer.java:13085)
> at
> org.apache.hadoop.hive.ql.parse.CalcitePlanner.analyzeInternal(CalcitePlanner.java:465)
> at
> org.apache.hadoop.hive.ql.parse.BaseSemanticAnalyzer.analyze(BaseSemanticAnalyzer.java:332)
> at org.apache.hadoop.hive.ql.Compiler.analyze(Compiler.java:224)
> at org.apache.hadoop.hive.ql.Compiler.compile(Compiler.java:109)
> at org.apache.hadoop.hive.ql.Driver.compile(Driver.java:508) {code}
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
