-- Fix embedding_e5 column dimension: 1024 → 768
-- The `intfloat/multilingual-e5-base` model outputs 768 dimensions, not 1024.
-- Run this in Supabase SQL Editor BEFORE re-running seed_embeddings.py.

-- Step 1: Drop old column (with wrong dimensions)
ALTER TABLE course_chunks DROP COLUMN IF EXISTS embedding_e5;

-- Step 2: Re-create with correct 768 dimensions
ALTER TABLE course_chunks ADD COLUMN embedding_e5 vector(768);
