fix db connections for example edge functions (#20889)

examples/edge-functions/supabase/.env.local.example

@@ -11,11 +11,13 @@ IPINFO_TOKEN="your https://ipinfo.io token"
 OPENAI_API_KEY="<YOUR API KEY HERE>"
 
 # postgres-on-the-edge & kysely-postgres
+# get your DB params and cert from the project dashboard
+# https://supabase.com/dashboard/project/_/settings/database
+# enable `Use connection pooling` and use `Transaction` mode
 DB_HOSTNAME=
 DB_PASSWORD=
+DB_USER=
 DB_SSL_CERT="-----BEGIN CERTIFICATE-----
-GET YOUR CERT FROM YOUR PROJECT DASHBOARD
-https://supabase.com/dashboard/project/_/settings/database
 -----END CERTIFICATE-----"
 
 # puppeteer 

examples/edge-functions/supabase/functions/kysely-postgres/index.ts

@@ -31,8 +31,8 @@ const pool = new Pool(
     tls: { caCertificates: [Deno.env.get('DB_SSL_CERT')!] },
     database: 'postgres',
     hostname: Deno.env.get('DB_HOSTNAME'),
-    user: 'postgres',
-    port: 5432,
+    user: Deno.env.get('DB_USER'),
+    port: 6543,
     password: Deno.env.get('DB_PASSWORD'),
   },
   1

examples/edge-functions/supabase/functions/postgres-on-the-edge/.env.example

@@ -1,2 +1,2 @@
 #Use PolyScale connection string with application_name parameter to get code-free database caching
-DATABASE_URL="postgresql:/DB_USERNAME:DB_PASSWORD@psedge.global:5432/postgres?application_name=POLYSCALE_CACHE_ID"
+DATABASE_URL="postgres://postgres.[PROJECT_REF]:[DB_PASSWORD]@psedge.global:5432?application_name=[APPLICATION_NAME]"

examples/edge-functions/supabase/functions/postgres-on-the-edge/index.ts

@@ -6,8 +6,8 @@ const pool = new Pool(
     tls: { enabled: false },
     database: 'postgres',
     hostname: Deno.env.get('DB_HOSTNAME'),
-    user: 'postgres',
-    port: 5432,
+    user: Deno.env.get('DB_USER'),
+    port: 6543,
     password: Deno.env.get('DB_PASSWORD'),
   },
   1