duplicate key value violates unique constraint

What it means

You tried to save something that must be unique (like a user's profile or an email) but it's already there. Often the app creates the same profile twice.

How to fix it: paste this prompt into your AI builder

Supabase returns "duplicate key value violates unique constraint". Find the insert causing it. If the record may already exist, use upsert with the correct onConflict column, or check before inserting. If a profile is also created by a database trigger on signup, remove the duplicate insert from the frontend. Don't drop the constraint or change unrelated code.

If the AI can't fix it: manual steps

1. Check Supabase Database, Triggers for an existing on_auth_user_created trigger that already creates profiles.

Where this happens

Seen in these AI app builders and editors:

Sources

• https://www.postgresql.org/docs/current/errcodes-appendix.html
• https://stackoverflow.com/questions/76108430/supabase-error-new-row-violates-row-level-security-policy-for-table

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