docs(sdb): add tb on SET search path errors MTA-6584 (#5642)

Author: SamyOubouaziz

pages/serverless-sql-databases/reference-content/known-differences.mdx

@@ -117,6 +117,8 @@ Serverless SQL Databases support the most popular PostgreSQL extensions. Refer t
     ```
     In this example, `SHOW timezone` will always display `Europe/Paris` without any impact from any other connection despite connection pooling.
 
+- `SET search_path TO` commands to use schemas works, but will be shared across multiple clients due to connection pooling, and will lead to unwanted effects. Refer to the [dedicated troubleshooting page](/serverless-sql-databases/troubleshooting/search-path-schema-errors/) for more information.
+
 - Security labels cannot be defined or changed.
 
     ```sql

pages/serverless-sql-databases/troubleshooting/index.mdx

@@ -44,4 +44,5 @@ productIcon: ServerlessDbProductIcon
   - [Solving Serverless SQL Databases connection timeouts](/serverless-sql-databases/troubleshooting/connection-timeout)
   - [Solving failing manual backup and restore operations](/serverless-sql-databases/troubleshooting/failing-backup-restore)
   - [Solving maximum prepared statements size errors](/serverless-sql-databases/troubleshooting/maximum-prepared-statements-reached)
+  - [Solving issues when setting search path to a schema](/serverless-sql-databases/troubleshooting/search-path-schema-errors/)
 </LinksList>

pages/serverless-sql-databases/troubleshooting/search-path-schema-errors.mdx

@@ -0,0 +1,33 @@
+---
+title: Solving errors while setting search path to schemas
+description: This page contains information to troubleshoot problems encountered while using SET search_path TO schema requests.
+tags: set search path to schema error problem bug 500 connection lost db pgbouncer pooling
+dates:
+  validation: 2025-10-10
+  posted: 2025-10-10
+---
+
+## Problem
+
+I am experiencing issues while using `SET` commands such as the following:
+
+```sql
+SET search_path TO my_schema
+```
+
+## Cause
+
+- `SET search_path TO` commands to use schemas works, but will be shared across multiple clients due to connection pooling, and will lead to unwanted effects.
+
+## Possible solutions
+
+- Use fully qualified schema names (`schema.table`) to perform stateless and self-contained transactions that do not rely on or modify session-level settings.
+
+- Perform the `SET` command in the same transaction as the request, using the `SET LOCAL` command so it applies to the current transaction only:
+
+```sql
+BEGIN;
+SET LOCAL search_path TO schema1;
+SELECT ... ;
+COMMIT; 
+```