Incident Dossier

The Phantom Read

A staged write is invisible to the very transaction that staged it. The customer adds ten units of stock, queries the on-hand count, and sees zero.

Initial failing signalread inside a tx cannot see its own pending writeExpected behavior: stock == 10 · actual behavior: stock == 0

Progress

1Reproduce the bugRun checks

2Edit the fixOpen

3Pass checksOpen

4Submit fixOpen

Reproduction Steps

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Likely area

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Hints reveal broad direction first, then narrow toward the suspect path without showing hidden tests or exact solution code.

TopicDatabases & Consistency

DifficultyMedium

Est. time18 min

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workspace

Outputread-onlyready$ prepare workspace

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