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https://issues.apache.org/jira/browse/IGNITE-26438?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Aleksandr Chesnokov updated IGNITE-26438:
-----------------------------------------
    Labels: IEP-35 ise  (was: ise perfStat)

> Normalize SQL plan: remove H2 system-generated subquery aliases
> ---------------------------------------------------------------
>
>                 Key: IGNITE-26438
>                 URL: https://issues.apache.org/jira/browse/IGNITE-26438
>             Project: Ignite
>          Issue Type: Improvement
>            Reporter: Aleksandr Chesnokov
>            Assignee: Aleksandr Chesnokov
>            Priority: Major
>              Labels: IEP-35, ise
>
> H2 automatically generates system aliases for derived tables in the form 
> {{_<number>}} (e.g., {{{}_10045{}}}).
> These aliases have no business meaning but cause logically identical SQL 
> plans to be stored as different texts, increasing storage size.
> This has two consequences:
>  # The *PerfStat* report becomes heavier than necessary.
>  # The *sql.plans.history* system view grows larger, storing redundant 
> entries.
> An example is given below.
> Before:
> {noformat}
> SELECT _10045.id, _10045.name
> FROM (
>     SELECT id, name
>     FROM users
> ) _10045
> WHERE _10045.id = 1;{noformat}
> After:
> {noformat}
> SELECT id, name
> FROM (
>     SELECT id, name
>     FROM users
> )
> WHERE id = 1;{noformat}



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