state-db-checkpoint-example

state-db-checkpoint-example

example-1:
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cache: {}

> create checkpoint #0
> write k=1 v=2

cache: { 1: (original = 1, current = 2) }

> revert to checkpoint #0

cache:
    Parity implementation: { 1: (original = 1, current = 1) }
    our (new) implementation: {}


example-2:
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cache: { 1: (original = 1, current = 2) }

> create checkpoint #0
> write k=1, v=1

cache: { 1: (original = 1, current = 1) }

> create checkpoint #1
> write k=1, v=3

cache: { 1: (original = 1, current = 3) }

> revert to checkpoint #1

cache: { 1: (original = 1, current = 1) }  --> if we delete from cache here, we will need another db load in the next step

> revert to checkpoint #0

cache: { 1: (original = 1, current = 2) }