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https://issues.apache.org/jira/browse/HIVE-24422?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17252750#comment-17252750
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Zhihua Deng edited comment on HIVE-24422 at 10/10/23 1:21 AM:
--------------------------------------------------------------

Seems I was wrong. In the trunk, the query 
{code:java}
with game_info as ( select distinct ext_id, dev_app_id, game_name from 
game_info_extend ) select count(game_name) from game_info;{code}
The game_info is materialized, this can reduce recomputing of game_info no 
matter how many times the game_info is referenced.


was (Author: dengzh):
Seems I am wrong. In the trunk, the query 
{code:java}
with game_info as ( select distinct ext_id, dev_app_id, game_name from 
game_info_extend ) select count(game_name) from game_info;{code}
The game_info is firstly materialized, this can reduce recomputing of game_info 
no matter how many times the game_info is referenced , the materialized view is 
used other than the table game_info for analyzing the tree later on.

> Throw SemanticException when CTE alias is conflicted with table name
> --------------------------------------------------------------------
>
>                 Key: HIVE-24422
>                 URL: https://issues.apache.org/jira/browse/HIVE-24422
>             Project: Hive
>          Issue Type: Improvement
>          Components: Parser
>            Reporter: Zhihua Deng
>            Assignee: Zhihua Deng
>            Priority: Major
>              Labels: pull-request-available
>          Time Spent: 0.5h
>  Remaining Estimate: 0h
>
> If the alias of CTE is conflicted with the table name, we use the alias 
> fetching the table other than replacing it with the ASTNode tree, this may 
> cause some confusing problems. For example:
> {noformat}
> create table game_info (game_name string);
> with game_info as (
> select distinct ext_id, dev_app_id, game_name
> from game_info_extend )
> select count(game_name) from game_info;{noformat}
> The query will return the number of rows of the table game_info, instead of 
> the game_info_extend. Maybe we should better throw an exception to avoid such 
> cases.
>  



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