Pseudo-unique constraint leaks duplicate accounts Debugging Lab

Pseudo-unique constraint leaks duplicate accountsDatabaseHardPreparing workspaceAutosaved

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Incident Dossier

Pseudo-unique constraint leaks duplicate accounts

A user signs up with an email that already exists in the system and gets a second account anyway. The 'email already exists' lookup is supposed to be a unique-key check, but it scans by the wrong attribute and never matches the existing row.

Initial failing signalfindAccountByEmail returns null for an email that existsExpected findAccountByEmail('alice@example.com') returns the row id=1 · received findAccountByEmail('alice@example.com') returns null

Progress

1Reproduce the bugRun checks

2Edit the fixOpen

3Pass checksOpen

4Submit fixOpen

Reproduction Steps

Run npm test.
Notice that findAccountByEmail returns null for emails that clearly exist in the fixture.
Trace the failure inside the helper — it scans an attribute that no row matches.
Identify the column-name mismatch and align the comparator with the column the unique constraint actually covers.
Confirm signup refuses duplicate emails and the accounts table does not grow.

Focus Mode

Start

src/accounts.js

Likely area

src/accounts.js

Progressive hints

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

TopicDatabase

DifficultyHard

Est. time28 min

Workspacecreating

Explorer

Preparing workspace files…

Evidence Map

Failing signal loaded from challenge API
Workspace files loaded from workspace API
Results rendered only after API run/submit

Autosaved

workspace

Outputread-onlyready$ workspace boot

Workspace booting...