indexrec: improve recommendations for queries with inequalities

[qiyanghe1998]

Fixes #102206

As for the tests, since !=, IS DISTINT FROM and IS NOT are categorized as range
index, so I copied similar tests with "R": R, EQ + R, J + R, EQ + J + R.

Release note: None

Epic: None

[cockroach-teamcity]

This change is 

[mgartner]

Very nice! Just left some optional nits.

Reviewed 2 of 2 files at r1, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @cucaroach and @qiyanghe1998)

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-- commits line 2 at r1:
nit: It's hard to make titles fit in ~72 characters — I don't always manage it — but you can try to make them less specific and put the details in the commit message body. For example, "indexrec: improve recommendations for queries with inequalities" is an option.

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-- commits line 7 at r1:
nit: "changed" makes it sound like you altered existing tests. maybe so I copied similar tests with "R": ...

[qiyanghe1998]

-- commits line 7 at r1:

Previously, mgartner (Marcus Gartner) wrote…

nit: "changed" makes it sound like you altered existing tests. maybe so I copied similar tests with "R": ...

fixed

[qiyanghe1998]

-- commits line 2 at r1:

Previously, mgartner (Marcus Gartner) wrote…

nit: It's hard to make titles fit in ~72 characters — I don't always manage it — but you can try to make them less specific and put the details in the commit message body. For example, "indexrec: improve recommendations for queries with inequalities" is an option.

Thanks. Great advice, fixed.

[qiyanghe1998]

bors r+

[mgartner]

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

[craig]

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[craig]

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[craig]

Build succeeded:

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