NoSQL
Preserve the technician’s observed repair revision
East reconnects at the required revision
The save receipt showed revision seven, but only a revision-six copy is reachable. Keep the session’s observed progress explicit.
BOTIE
The inputs we are comparing
Observed replica states
The fresh copy is disconnected
[
{
"id": "east",
"version": 7,
"reachable": false
},
{
"id": "west",
"version": 6,
"reachable": true
}
]The fresh copy reconnects
[
{
"id": "east",
"version": 7,
"reachable": true
},
{
"id": "west",
"version": 6,
"reachable": true
}
]Minimum revision for this session
Same in both cases
7
Result for the fresh copy is disconnected
wait
The highest revision is unreachable
This check uses the pieces from “Choose a copy that satisfies the session floor”.
BOTIE
- Observed replica states
[ { "id": "central", "version": 12, "reachable": false }, { "id": "south", "version": 10, "reachable": true }, { "id": "north", "version": 10, "reachable": true } ]- Minimum revision for this session
10
Use a number, text, or an array matching the requested result. For a matrix, put each row in brackets. Saving your prediction runs your current construction on these inputs and checks the earlier examples too.
Build a construction in the workspace above first. This case will test those pieces.
Why does choosing the largest visible revision fail to prove that no unseen replica has a later write?
The model enforces a supplied session floor. It does not implement a global latest-value oracle.
The supplied revisions are observations in a toy single-record sequence. They do not implement linearizability, replication or failure detection.
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