Client Initialization Error Unsolvable (Next.js app with Supabase)

[mlaksi]

Question

I'm losing my mind over this error, I tried everything, it started as Supabase P1001, I restarted db, I changed passwords, I checked env strings.... Nothing works!

How to reproduce (optional)

Expected behavior (optional)

No response

Information about Prisma Schema, Client Queries and Environment (optional)

// Add your schema.prisma

// Add any relevant Prisma Client queries here

• OS:

• Database:

• Node.js version:

• Run prisma -v to see your Prisma version and paste it

[ericgitangu]

Nine times out of ten this is the IPv6 thing. Supabase's direct connection (db.<ref>.supabase.co:5432) is IPv6-only now, and most dev networks plus most serverless runtimes are IPv4. P1001 is exactly what you get when DNS resolves but the route can't be opened, which matches the symptom of "everything looks right and nothing works."

Switch your DATABASE_URL to the Supavisor pooler, which is IPv4-reachable and what Next.js/Vercel runtimes actually want:

DATABASE_URL="postgresql://postgres.<ref>:<pwd>@aws-0-<region>.pooler.supabase.com:6543/postgres?pgbouncer=true&connection_limit=1"
DIRECT_URL="postgresql://postgres.<ref>:<pwd>@aws-0-<region>.pooler.supabase.com:5432/postgres"

Then in schema.prisma set directUrl = env("DIRECT_URL") so migrations hit session mode (5432) and the runtime client uses transaction mode (6543). Note the username is postgres.<project-ref>, not just postgres, on the pooler.

If special chars in the password are URL-encoded and it still fails, hit the same string with psql first, that tells you whether it's network or Prisma before you keep rotating credentials.

[Rish-2006]

P1001 with Supabase + Prisma is one of the most misleading errors in the ecosystem — the message implies a network problem, but the real cause is almost always something else. Since you've already tried the basics, here's the full layered diagnostic. Work through these in order.

---

1. You're using the wrong connection string for the wrong purpose

This is the #1 cause by a wide margin. Supabase gives you two strings and they are not interchangeable:

String	Host	Port	Purpose
Pooled (Supavisor)	aws-0-*.pooler.supabase.com	6543	Runtime queries (DATABASE_URL)
Direct	db.[ref].supabase.co	5432	Migrations (DIRECT_URL)

Your .env must look like this:

# Pooled — runtime queries
DATABASE_URL="postgresql://postgres.[ref]:[PASSWORD]@aws-0-[region].pooler.supabase.com:6543/postgres?pgbouncer=true&connect_timeout=30"

# Direct — migrations only
DIRECT_URL="postgresql://postgres:[PASSWORD]@db.[ref].supabase.co:5432/postgres?connect_timeout=30"

And your schema.prisma:

datasource db {
  provider  = "postgresql"
  url       = env("DATABASE_URL")
  directUrl = env("DIRECT_URL")
}

⚠️ Don't copy from the general "Connection Info" tab. Go to Supabase Dashboard → Connect → ORMs and copy the strings shown there — they're pre-formatted for Prisma.

---

2. Special characters in your password silently break the URL

If your password contains any of @ # ! $ % & = + ? /, the URL parser misparsed it and you get P1001 with zero indication why.

Fix: Go to Supabase Dashboard → Project Settings → Database → Reset database password. Use only alphanumeric characters (no symbols). Then rebuild your .env with the new password.

Alternatively percent-encode it (@ → %40, # → %23, etc.) — but resetting is cleaner.

---

3. Your Supabase project is paused (free tier)

Free-tier projects are automatically paused after 1 week of inactivity. A paused project returns P1001 because the DB isn't running at all.

Check: Open your Supabase dashboard — if you see a "Project paused" banner, click Restore and wait 2–3 minutes before retrying.

---

4. Missing connect_timeout causes false P1001s on cold starts

Prisma's default timeout is 5 seconds. Supabase's pooler sometimes takes longer to spin up a connection on first request, causing Prisma to interpret the delay as "unreachable."

Add connect_timeout=30 to both URLs (as shown in step 1).

---

5. Verify your .env is actually being read

npx prisma debug

This prints the exact DATABASE_URL and DIRECT_URL Prisma is actually using. You may find it's reading a stale value, a parent directory's .env, or an empty string.

Also check for hidden characters or Windows CRLF line endings:

cat -A .env | grep DATABASE_URL

If you see ^M at the end of the line, the carriage return is being appended to your URL — which breaks it silently.

---

6. Test the connection outside of Prisma

psql "postgresql://postgres.[ref]:[PASSWORD]@db.[ref].supabase.co:5432/postgres"

• If psql connects but Prisma doesn't → the problem is in your connection string format or schema config
• If psql also fails → the problem is network or Supabase-side

You can also open the Supabase Table Editor in your browser — if your tables load, the database is running fine.

---

7. IPv4 vs IPv6 mismatch (Docker / WSL2 / CI)

Docker and some CI environments resolve hostnames to IPv6 by default, but Supabase's free-tier pooler only supports IPv4. This causes P1001 even when the database is perfectly healthy.

Fix: Add ?family=4 to your connection string to force IPv4, or use the direct connection URL instead of the pooler.

---

Quick checklist

• Using ORMs tab strings from Supabase Connect (not raw connection info)
• DATABASE_URL → pooler.supabase.com with pgbouncer=true
• DIRECT_URL → db.[ref].supabase.co (no pgbouncer)
• Password has no special characters (or is percent-encoded)
• Project is not paused in the Supabase dashboard
• connect_timeout=30 on both URLs
• npx prisma debug confirms the right values are loaded
• psql direct connection test passes

If you share your redacted connection strings (replace password with [PASS] and project ref with [REF]) and the output of npx prisma -v, it'll be easy to pinpoint exactly which case applies to you.

[nurul3101]

Is the issue resolved now or are you still running into this?

[github-actions[bot]]

Hi,

As we have not heard back from you, we are closing this discussion to keep our discussions organized.

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