willhaben-tracker/docs/phase-0/task-search-path-fix.md

Task: search_path consistency fix

Description

There is a mismatch between the database schema configuration and where tables actually live:

In db.py (_init_connection):

await conn.execute("SET search_path TO willhaben_tracker")

But in supabase-migration.sql:

• The migration file has SET search_path TO willhaben_tracker; but the actual tables were created in public schema (not willhaben_tracker) when manually applied.
• The original local Supabase migrations used public schema.

This creates two problems:

1. If a connection does NOT run _init_connection, queries to bare table names (SELECT FROM keywords) fail with "relation does not exist".
2. Tools that connect directly (pgAdmin, DBeaver, PostgREST) won't find the tables without explicit schema qualification or their own search_path config.

Decision: Remove custom schema, use public for everything

Since Supabase uses public by default and all existing tools/GRANTs in post-boot.sql target public, we simplify by removing the willhaben_tracker schema entirely.

Rationale

Factor	Custom Schema (willhaben_tracker)	Public Schema
Supabase Studio compatibility	Requires manual config	✅ Works out of box
PostgREST/Kong access	Needs search_path override	✅ Default
Direct pgAdmin/DBeaver access	Must set schema per-connection	✅ Always visible
Grant statements in post-boot.sql	❌ Targets wrong schema	✅ Already correct
Code changes needed	Minimal (remove one line)	Minimal

Architecture

BEFORE (broken):
  db.py init: SET search_path TO willhaben_tracker
  tables live in: public.keywords, public.ads, ...
  Result: queries fail because search_path != table location

AFTER (fixed):
  db.py init: REMOVED (no custom search_path)
  tables live in: public.keywords, public.ads, ...
  Result: all connections find tables via default 'public' schema

Implementation Details

1. Remove SET search_path from db.py

Current:

async def _init_connection(conn: asyncpg.Connection) -> None:
    await conn.execute("SET search_path TO willhaben_tracker")

After:

# Removed entirely - using default public schema

The _init_connection function can be removed, and init=_init_connection removed from create_pool(). Alternatively keep the callback but make it a no-op for future use:

async def _init_connection(conn: asyncpg.Connection) -> None:
    # Reserved for future connection-level settings (e.g., timezone)
    pass

2. Clean up migration files

• Remove SET search_path TO willhaben_tracker; from supabase-migration.sql / 01-schema.sql
• Ensure all tables are explicitly created in the default schema (no need for prefix — that's already what happens)

3. Update post-boot.sql grants if needed

Current grants already target public:

GRANT USAGE ON SCHEMA public TO supabase_admin;

→ ✅ Already correct, no change needed.

4. Add schema qualification to migration file (defensive)

To be explicit and future-proof, the migration can qualify the schema:

-- Instead of implicit public.keywords
CREATE TABLE IF NOT EXISTS public.keywords (...)

This is optional but makes it unambiguous where tables live. For simplicity we'll keep implicit public since that's the default everywhere.

Acceptance Criteria

• Removing _init_connection from db.py does not break any query (all table names resolve correctly)
• Connecting to the database via pgAdmin/DBeaver shows all tables without schema configuration
• The healthcheck endpoint DB check works without custom search_path
• No "relation does not exist" errors in worker logs after redeploy
• Migration SQL file no longer references willhaben_tracker schema