Describe the problem/error/question
I’m building a RAG workflow using Supabase (pgvector) and the Embeddings Google Gemini node. My goal is to use Google’s latest embedding model, gemini-embedding-exp-03-07, for its high-quality 3072-dimension output.
The issue is that the Embeddings Google Gemini node seems to default to, or is limited to, the text-embedding-004 model which only outputs 768-dimension vectors. This causes a dimension mismatch when my Supabase table is correctly configured for vector(3072).
The workflow only succeeds when I downgrade both the Supabase table and the n8n node to use the 768-dimension default. Manually typing models/gemini-embedding-exp-03-07 into the Model field does not resolve the issue, suggesting the node is not handling the 3072d output correctly.
Has anyone found a way to use the 3072-dimension models, or is this a current limitation?
What is the error message (if any)?
When the Supabase table is set to vector(3072), the Supabase Vector Store node fails with the following error, which originates from the dimension mismatch:
Error inserting: vector must have at least 1 dimension 400 Bad Request
Share the output returned by the last node
The Embeddings Google Gemini node returns [empty array] when the Supabase table is expecting 3072 dimensions, even though the upstream nodes (Default Data Loader, Text Splitter) are confirmed to be passing non-empty data.
Information on your n8n setup
- n8n version:latest
- Database (default: SQLite): supabase
- n8n EXECUTIONS_PROCESS setting (default: own, main): own
- Running n8n via (Docker, npm, n8n cloud, desktop app): docker_google cloud
- Operating system: linux debian