Add an example of LVMT to LvmtStorage struct

[rongma7]

This change is 

[ChenxingLi]

Reviewed 4 of 6 files at r1, all commit messages.
Reviewable status: 4 of 6 files reviewed, 1 unresolved discussion (waiting on @rongma7)

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src/middlewares/versioned_flat_key_value/mod.rs line 141 at r1 (raw file):

    to_confirm_start_height: usize,
    to_confirm_ids_maps: Vec<(CommitID, BTreeMap<T::Key, impl Into<Option<T::Value>>>)>,
    is_first_t: bool,

What does it mean?

[rongma7]

Reviewable status: 2 of 7 files reviewed, 1 unresolved discussion (waiting on @ChenxingLi)

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src/middlewares/versioned_flat_key_value/mod.rs line 141 at r1 (raw file):

Previously, ChenxingLi (Chenxing Li) wrote…

What does it mean?

Done.

[ChenxingLi]

Reviewed 3 of 5 files at r2, 1 of 1 files at r3.
Reviewable status: 6 of 7 files reviewed, 3 unresolved discussions (waiting on @rongma7)

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src/middlewares/versioned_flat_key_value/pending_part/versioned_map.rs line 126 at r3 (raw file):

        &mut self,
        commit_id: S::CommitId,
    ) -> PendResult<(usize, Vec<S::CommitId>, Vec<KeyValueMap<S>>), S> {

Consider define a struct for the return value here.

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src/middlewares/versioned_flat_key_value/mod.rs line 194 at r3 (raw file):

    write_schema: &D::WriteSchema,
) -> Result<()> {
    let commit_id_table = Arc::new(db.view::<CommitIDSchema>()?);

Why do you need Arc?

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src/middlewares/versioned_flat_key_value/mod.rs line 220 at r3 (raw file):

    }

    std::mem::drop(commit_id_table);

The object will be dropped automatically at the end of the function. It is not necessary to manually drop them.

[rongma7]

Reviewable status: 3 of 9 files reviewed, 3 unresolved discussions (waiting on @ChenxingLi)

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src/middlewares/versioned_flat_key_value/mod.rs line 194 at r3 (raw file):

Previously, ChenxingLi (Chenxing Li) wrote…

Why do you need Arc?

Done.

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src/middlewares/versioned_flat_key_value/mod.rs line 220 at r3 (raw file):

Previously, ChenxingLi (Chenxing Li) wrote…

The object will be dropped automatically at the end of the function. It is not necessary to manually drop them.

Done.

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src/middlewares/versioned_flat_key_value/pending_part/versioned_map.rs line 126 at r3 (raw file):

Previously, ChenxingLi (Chenxing Li) wrote…

Consider define a struct for the return value here.

Done.

[ChenxingLi]

Reviewed 4 of 6 files at r4, all commit messages.
Reviewable status: 7 of 9 files reviewed, 2 unresolved discussions

[ChenxingLi]

Reviewed 5 of 6 files at r5, 1 of 1 files at r6, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @rongma7)