Do not implicitly read pk and version columns in lonely parts if unnecessary

[canhld94]

Changelog category (leave one):

• Performance Improvement

Changelog entry (a user-readable short description of the changes that goes to CHANGELOG.md):

• Do not implicitly read pk and version columns in lonely parts if unnecessary

When query has FINAL but we enable do_not_merge_across_partitions_select_final, no need to implicitly read pk and version columns for lonely parts.

Implementation: construct two group of pipes

• merging pipes: with normal FINAL logic
• non-merging pipes: to read from lonely parts, will not implicitly read pk and version columns as well as computing sorting expression

Convert header if needed (final header is from non-merging pipes, if it's not empty) and unite all pipes

Inspired by #43296

Information about CI checks: https://clickhouse.com/docs/en/development/continuous-integration/

[canhld94]

cc @KochetovNicolai

[alexey-milovidov]

This is a huge improvement! I didn't expect we don't have it already :)

[robot-ch-test-poll3]

This is an automated comment for commit 8a9b544 with description of existing statuses. It's updated for the latest CI running

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[canhld94]

The stateless test is flaky because it relies on merges, will try to make it stable.
Performance test:

0.081 | 0.062 | -1.301x | -0.232 | 0.215 | parallel_final | 0 | SELECT count() FROM collapsing_final_16p_ord final

--> indeed this bring performance improvement (will be more clear if we set max_threads=1). Will add own performance test as well.

[canhld94]

cc @jorisgio

[canhld94]

@KochetovNicolai @alexey-milovidov pls help to review when you have time [THANKS]

[den-crane]

before

select max(a) from t final settings do_not_merge_across_partitions_select_final=1;
1 row in set. Elapsed: 1.912 sec. Processed 214.93 million rows, 5.48 GB (112.41 million rows/s., 2.86 GB/s.)
Peak memory usage: 1.11 MiB.

after

select max(a) from t final settings do_not_merge_across_partitions_select_final=1;
1 row in set. Elapsed: 0.535 sec. Processed 214.93 million rows, 1.72 GB (402.05 million rows/s., 3.22 GB/s.)
Peak memory usage: 266.12 KiB.

And Peak memory usage is beautiful.

baseline

select max(a) from t;
1 row in set. Elapsed: 0.540 sec. Processed 214.93 million rows, 1.72 GB (397.84 million rows/s., 3.18 GB/s.)
Peak memory usage: 59.14 KiB.