Issue with vercel connection to supabase

# Vercel Support Ticket: Environment Variables Not Updating in Deployments

## Issue Summary

Environment variables are not being picked up by deployments despite being correctly set in the Vercel dashboard. The `DATABASE_URL` environment variable shows the correct value in the dashboard, but deployments continue to use an old cached value.

- **Vercel CLI Version**: 48.8.2

- **Next.js Version**: 14.2.25

## Problem Description

### What’s Happening

1. We update `DATABASE_URL` in Vercel Dashboard → Settings → Environment Variables

2. The value is correctly saved (verified in the dashboard)

3. We redeploy the application

4. The deployment still uses the **old** environment variable value

### Diagnostic Evidence

We have a diagnostic endpoint (`/api/test-db-staging`) that logs the actual `DATABASE_URL` value being used:

**Current Behavior:**

- `databaseUrlLength: 111` (old connection string length)

- `databaseUrlFull: “postgresql://postgres:XXXXXXXXXXXXX@db.ficbirpcqotketdpqirf.supabase.co:5432/postgres?sslmode=require”` (old direct connection)

**Expected Behavior:**

- `databaseUrlLength: ~149` (new connection pooler string length)

- `databaseUrlFull: “postgresql://postgres.ficbirpcqotketdpqirf:XXXXXXXXXXXXXXXXXX@aws-0-us-east-1.pooler.supabase.com:6543/postgres?sslmode=require”` (new pooler connection)

### Environment Variable Configuration

- **Variable Name**: `DATABASE_URL`

- **Current Value in Dashboard**: `postgresql://postgres.ficbirpcqotketdpqirf:xxxxxxxxxxxxxxx@aws-0-us-east-1.pooler.supabase.com:6543/postgres?sslmode=require`

- **Environment**: Set for **All** (Production, Preview, Development)

- **Status**: Shows as saved correctly in dashboard

## Steps Taken to Resolve

1. Updated environment variable in Vercel dashboard

2. Verified value is correct in dashboard (shows pooler URL)

3. Set variable for All environments (Production, Preview, Development)

4. Deleted and recreated the environment variable

5. Redeployed multiple times (with and without cache)

6. Unchecked “Use existing build cache” during redeploy

7. Pushed code changes to trigger fresh deployments

8. Verified no `.env` files or `vercel.json` are overriding the variable

9. Confirmed no duplicate `DATABASE_URL` entries exist

## Technical Details

### Diagnostic Endpoint Code

```typescript

// src/app/api/test-db-staging/route.ts

export async function GET() {

const diagnostics = {

hasDatabaseUrl: !!process.env.DATABASE_URL,

databaseUrlLength: process.env.DATABASE_URL?.length || 0,

databaseUrlFull: process.env.DATABASE_URL || ‘NOT SET’,

};

// … connection test

}

```

### Current Diagnostic Output

```json

{

“success”: false,

“error”: “Database connection failed”,

“diagnostics”: {

“hasDatabaseUrl”: true,

“databaseUrlLength”: 111,

“databaseUrlFull”: “postgresql://postgres:xxxxxxxxxxxxxx@db.ficbirpcqotketdpqirf.supabase.co:5432/postgres?sslmode=require”

}

}

```

### Expected Diagnostic Output

```json

{

“success”: true,

“diagnostics”: {

“hasDatabaseUrl”: true,

“databaseUrlLength”: 149,

“databaseUrlFull”: “postgresql://postgres.ficbirpcqotketdpqirf:xxxxxxxxxxxxx@aws-0-us-east-1.pooler.supabase.com:6543/postgres?sslmode=require”

}

}

```

## Impact

This prevents the application from connecting to the database, causing all API routes to return 500 errors:

- `/api/homes` → 500

- `/api/profile` → 500

- `/api/climate-zones` → 500

- `/api/property-types` → 500

- All other database-dependent routes → 500

## Requested Help

1. **Why is the deployment using the old environment variable value?**

- The dashboard shows the correct value

- But deployments continue using the old value

2. **Is there a Vercel caching mechanism we need to clear?**

- We’ve tried redeploying without cache

- Still shows old value

3. **Are there any project settings that might override environment variables?**

- We’ve checked vercel.json (empty)

- No .env files in the repository

4. **Is there a way to verify environment variables are loaded correctly?**

- Our diagnostic endpoint shows what’s actually being used

- It consistently shows the old value

## Additional Information

- **Environment Variable Length**: Old value is 111 characters, new value should be ~149 characters

- **Connection String Format**: Changing from direct connection (port 5432) to connection pooler (port 6543)

- **Database**: Supabase PostgreSQL

- **Region**: us-east-1

- **Deployment Environment**: Staging branch deploys to Production environment

## Expected Resolution

The deployment should use the environment variable value as set in the Vercel dashboard, not a cached or old value.

**Can you please help us understand why environment variables aren’t updating in deployments?**

I’m unfortunately not seeing any big red flags here that might point to an issue. The builds are running properly and are tagged as production and there is no cache being used here

You seem to have two separate Vercel projects set up currently, one for production and one for staging. Is there any chance you’re checking the “production” project’s variables while the separate project you’re using for staging is left on the old values?

The idiomatic way to do this would be to have a single project and go to Settings -> Environments to set up a custom staging environment tagged to the staging branch with its own domain, which will ensure they all stay in sync

Unfortunately I have very limited visibility into your current environment variable structure (for security reasons) so I can’t check on your behalf, but I wonder if there’s a bug where the branch named “staging” is triggering a heuristic that causes it to use Preview environment variables instead? That would seem strange to me but everything else looks correct

If your production project appears to be working correctly, I’d recommend consolidating them as I’ve outlined above and then if you run into the issue again you should be able to notice exactly when it happens for diagnosis

Thanks, Jacob. Yes, my production project is working fine, I am using vercel for the first time ever. I am going to. consolidate and see if this triggers anything that could be of help.