[jira] [Created] (IGNITE-9933) SQL: lazy mode isn't used on reduce step

["Taras Ledkov (JIRA)" <ji...@apache.org>]

Taras Ledkov created IGNITE-9933:
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             Summary: SQL: lazy mode isn't used on reduce step
                 Key: IGNITE-9933
                 URL: https://issues.apache.org/jira/browse/IGNITE-9933
             Project: Ignite
          Issue Type: Improvement
          Components: sql
    Affects Versions: 2.6
            Reporter: Taras Ledkov
            Assignee: Taras Ledkov


Lazy execution is introduced as default by IGNITE-9171.
But queries are executed lazy only in  map phase now.

So, we have introduce lazy query execution on reduce step when merge table is user to prevent waits for fetch all results on reduce step and excessive allocate memory.

It will be applicable for queries sorted by index.

Attention: when reduce query is executed in lazy mode the release remote resource and query cancellation must be changed.

See:
- {{GridReduceQueryExecutor#query}}
- {{GridReduceQueryExecutor#releaseRemoteResources}}




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