Detailed, transparent comparisons with popular databases. See where HeliosDB excels and where alternatives may be a better fit.
| Aspect | HeliosDB | PostgreSQL + pgvector |
|---|---|---|
| Setup Time | 5 minutes | 30+ minutes |
| Vector Search | Native HNSW + PQ | Extension (no PQ) |
| Resident Vector RAM | ~16× smaller (PQ codes) | Full vectors in RAM |
| Restart Behaviour | Durable, no rebuild | Survives, but warmup cost |
| Online Deletes | Neighbour repair | Tombstones (recall rot) |
| Filtered KNN | In-traversal | Post-filter top-k |
| License | Apache 2.0 (hostable) | PostgreSQL License |
| Database Branching | Built-in SQL | Third-party tools |
| Time Travel | SQL syntax | PITR only |
| Schema Inference | REST API | — |
| Deployment | Single binary | Server + extension |
| Aspect | HeliosDB Nano | SQLite + vector extension |
|---|---|---|
| Vector Search | HNSW built in (PQ via build feature) | Varies by extension & version |
| Full-Text Search | BM25, unstemmed, no phrase queries | FTS5: stemming, phrase, persisted index |
| Row-Level Security | Yes — embedded only, not over the wire | Application-level only |
| Server Mode | PostgreSQL & MySQL wire | None built in |
| Time Travel | AS OF queries, within retention | No |
| Encryption | AES-256-GCM, off by default | SEE or third-party builds |
| Maturity | Young, active correctness work | Decades of production use |
| Aspect | HeliosDB | Supabase |
|---|---|---|
| Self-Hosted | Single binary | Complex stack |
| Vector Search | Native HNSW + PQ | pgvector extension |
| Database Branching | SQL commands | Dashboard only |
| Self-Hosted Price | $0 | $25/mo minimum |
| Offline Support | Full | Limited |
| Aspect | HeliosDB Nano | MySQL 8.0 |
|---|---|---|
| Docker Image | 32 MB | 570 MB |
| RAM Usage | ~30 MB | ~400 MB |
| Startup Time | 10ms | 5-10s |
| Embedded Mode | Yes | No |
| PostgreSQL Protocol | Native | — |
| Vector Search | Native HNSW + PQ | Plugin required |
| Database Branching | SQL commands | — |
| Time Travel | AS OF TIMESTAMP | Binlog replay only |
| Encryption | AES-256-GCM built-in | Enterprise only |
| WordPress | ✓ Native mysqli | ✓ Native |
| Backup | Copy single file | mysqldump / xtrabackup |
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