fix: solve some inconsistencies between code and comments

[YichiZhang0613]

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Summary

Solve the inconsistencies between code and comments which are proposed in #15390

• Fixes #15390

Tests

• [ ] Unit Test
• [ ] Logic Test
• [ ] Benchmark Test
• [x] No Test - Explain why

Type of change

• [x] Bug Fix (non-breaking change which fixes an issue)
• [ ] New Feature (non-breaking change which adds functionality)
• [ ] Breaking Change (fix or feature that could cause existing functionality not to work as expected)
• [x] Documentation Update
• [ ] Refactoring
• [ ] Performance Improvement
• [ ] Other (please describe):

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This change is 

[Dousir9]

I think assert in this PR is unnecessary as Rust automatically checks bounds on array accesses (and panic's if it is out of bounds).

[YichiZhang0613]

I think assert in this PR is unnecessary as Rust automatically checks bounds on array accesses (and panic's if it is out of bounds). In my opinion, the Rust official documentation recommends that to prevent array index out-of-bounds errors, it is recommended to use methods such as assert! for verification, or use built-in methods such as get and insert instead of directly accessing elements. This approach can handle potential errors more safely. In addition, conscious processing can prompt meaningful information during panic, thus achieving better user interaction. What's more, many other methods in databend also have assert! checks for out-of-bounds situations, which can also better maintain consistency of whole project.

[Dousir9]

I think assert in this PR is unnecessary as Rust automatically checks bounds on array accesses (and panic's if it is out of bounds). In my opinion, the Rust official documentation recommends that to prevent array index out-of-bounds errors, it is recommended to use methods such as assert! for verification, or use built-in methods such as get and insert instead of directly accessing elements. This approach can handle potential errors more safely. In addition, conscious processing can prompt meaningful information during panic, thus achieving better user interaction. What's more, many other methods in databend also have assert! checks for out-of-bounds situations, which can also better maintain consistency of whole project.

For a simple data structure like Vec, we don't use get to access it, Rust automatically checks bounds on array accesses, so assert is unnecessary, we can add some comments for it. In addition, assert is not free, it will affect performance.

[YichiZhang0613]

I think assert in this PR is unnecessary as Rust automatically checks bounds on array accesses (and panic's if it is out of bounds). In my opinion, the Rust official documentation recommends that to prevent array index out-of-bounds errors, it is recommended to use methods such as assert! for verification, or use built-in methods such as get and insert instead of directly accessing elements. This approach can handle potential errors more safely. In addition, conscious processing can prompt meaningful information during panic, thus achieving better user interaction. What's more, many other methods in databend also have assert! checks for out-of-bounds situations, which can also better maintain consistency of whole project.

For a simple data structure like Vec, we don't use get to access it, Rust automatically checks bounds on array accesses, so assert is unnecessary, we can add some comments for it. In addition, assert is not free, it will affect performance.

OK, I accept your point and modified my PR accordingly.