Fix · Supabase and databases

Realtime updates do not arrive

Not checked against the vendor's current screens

What you may see

My page does not update live when data changes
The subscription connects but no events come

Most likely cause

Realtime is not turned on for that table, a security rule hides the rows from the listener, or the channel closes before it is ready.

Check first (about two minutes)

In the dashboard check whether realtime is enabled for the table (the place may be labelled differently).

The fix prompt

What you type here never leaves your browser. The search runs on this page, and nothing is sent to a server or to an AI.

The exact error or what you see

What you did before it happened

Kept only in this browser, on this device. Keys and passwords are removed before anything is saved.

Prompt language

You are a careful senior engineer who knows Supabase (database, login and file storage) and explains it to people who are not developers. I am not a developer, so explain every step in plain words and tell me exactly which button, menu or command you mean. If you are not sure about something, say so; do not guess.

Menu and button names change over time. If you cannot find a button or page I mention, say so and tell me what to look for instead of guessing.

THE PROBLEM
Realtime updates do not arrive

THE EXACT ERROR OR WHAT I SEE
[paste the exact error here]

WHAT I DID BEFORE IT HAPPENED
[write in a few words what you did before it happened]

MOST LIKELY CAUSE
Realtime is not turned on for that table, a security rule hides the rows from the listener, or the channel closes before it is ready.

DO THESE STEPS, IN THIS ORDER
1. Check the subscription code: channel name, table, event type and filter.
2. Make sure the table is added to the realtime publication through a migration, and that a select policy lets the listener see the rows.
3. Unsubscribe when the page closes to avoid duplicates.
Stop and tell me if what you see does not match a step. Do not skip ahead.

CHECK THAT IT WORKED
- Changing a row in the dashboard shows up in the open page within seconds.
Tell me exactly what I should see on the screen when it works.

DO NOT CHANGE
- Do not make the table public to test.
- Anything I did not ask about: the design, the text, other pages, other settings or the data.
- Do not delete files, data or branches, do not reset or force-push, and do not rewrite history, unless you first show me exactly what would be lost and I say yes.
- Do not paste, print or ask me to paste a password or secret key into this chat. If one is needed, tell me which settings page of the right service to store it in.

WHEN YOU FINISH
Explain in simple words what you changed (file by file or setting by setting), why you changed it, and how I can undo it.

Paste it into Claude, ChatGPT, Gemini or Cursor, then follow what it says.

After you tried it, did it work?

Steps

Check the subscription code: channel name, table, event type and filter.
Make sure the table is added to the realtime publication through a migration, and that a select policy lets the listener see the rows.
Unsubscribe when the page closes to avoid duplicates.

Do not do this

Do not open a new subscription on every render.
Do not make the table public to test.

Try another entry