release-23.2: ttljob: fix job to handle composite PKs

[rafiss]

Backport 2/2 commits from #116988 and #117510

/cc @cockroachdb/release

Release justification: high priority bug fix

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Certain types, like decimals and collated strings, store their contents in the value of the encoded KeyValue. The ttljob code that decodes the span bounds into datums for the purpose of creating SQL query bounds previously did not take this into account.

fixes #116845
Release note (bug fix): Fixed a bug in the row-level TTL job that would
cause it to skip expired rows if the primary key of the table included
columns of the collated string type. This bug was present since the
initial release of row-level TTL in v22.2.0.

[blathers-crl]

Thanks for opening a backport.

Please check the backport criteria before merging:

• Backports should only be created for serious
  issues or test-only changes.
• Backports should not break backwards-compatibility.
• Backports should change as little code as possible.
• Backports should not change on-disk formats or node communication protocols.
• Backports should not add new functionality (except as defined
  here).
• Backports must not add, edit, or otherwise modify cluster versions; or add version gates.
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  TL. For more information as to how that review should be conducted, please consult the backport
  policy.

If your backport adds new functionality, please ensure that the following additional criteria are satisfied:

• There is a high priority need for the functionality that cannot wait until the next release and is difficult to address in another way.
• The new functionality is additive-only and only runs for clusters which have specifically “opted in” to it (e.g. by a cluster setting).
• New code is protected by a conditional check that is trivial to verify and ensures that it only runs for opt-in clusters. State changes must be further protected such that nodes running old binaries will not be negatively impacted by the new state (with a mixed version test added).
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  channel (#db-backports-point-releases or #db-backports-XX-X-release) for awareness and discussion.

Also, please add a brief release justification to the body of your PR to justify this
backport.

[cockroach-teamcity]

This change is 

[DrewKimball]

Reviewed 8 of 8 files at r1, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @adityamaru, @rafiss, and @yuzefovich)

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-- commits line 11 at r1:
Do you think it would be worth removing the mention of decimal here, since it shouldn't actually cause skipped rows?

[yuzefovich]

Reviewed 6 of 8 files at r1, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @adityamaru and @DrewKimball)

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-- commits line 11 at r1:

Previously, DrewKimball (Drew Kimball) wrote…

Do you think it would be worth removing the mention of decimal here, since it shouldn't actually cause skipped rows?

Also perhaps mention that the bug was introduced when TTL feature was added (with concrete version).

[yuzefovich]

Maybe hold off on merging this for a few days to let flakes like #117543 shake out on master?

[rafiss]

I agree, I was planning to wait a bit

[rafiss]

Reviewable status: complete! 0 of 0 LGTMs obtained (and 1 stale) (waiting on @adityamaru, @DrewKimball, and @mgartner)

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-- commits line 11 at r1:

Previously, yuzefovich (Yahor Yuzefovich) wrote…

Also perhaps mention that the bug was introduced when TTL feature was added (with concrete version).

updated on both accounts

[mgartner]

Reviewable status: complete! 1 of 0 LGTMs obtained (and 1 stale) (waiting on @adityamaru and @DrewKimball)