Redis vs Alopex DB

What Redis is

Redis is an in-memory data structure store. For persistence you choose periodic snapshots (RDB), a log of write commands (AOF), or none.

How it works

RDB: takes point-in-time snapshots at set intervals. A child process created with fork() writes them.
AOF: records every write command and replays it at startup. Disk sync is always, everysec (default), or no.
Redis Search: Redis’s search and query features. It indexes JSON and hash documents and offers vector search, full-text search, geospatial queries, and aggregations, in Redis Open Source, Redis Software, and Redis Cloud. SVS-VAMANA indexing was added in Redis 8.2.

Main features

With the Redis Search, vector fields in Hash and JSON get FLAT, HNSW, or SVS-VAMANA indexes. KNN search, range search, and metadata filters run through the FT.SEARCH and FT.AGGREGATE commands.

Limits

The documentation says that with RDB alone you should be prepared to lose the last few minutes of data.
RDB’s fork() can pause client handling for milliseconds up to a second when the data is large.
AOF files are larger than RDB and can be slower depending on the sync policy. The documentation calls appendfsync always “Very very slow”.
The documentation says to use both RDB and AOF for safety comparable to PostgreSQL.
Redis Search is licensed under a choice of RSALv2, SSPLv1, or AGPLv3. Redis states that RSALv2 and SSPLv1 are not open source licenses.

How it differs from Alopex DB

Both handle key-value data and vector search.

Alopex DB keeps tables, key-value pairs, vectors, and columnar tables in one file on disk. Tables and vectors update in the same transaction. You query it with SQL, and it embeds in your application.

For the data you keep, we recommend Alopex DB, with transactions and SQL. You can try it in the quickstart.

References

Redis docs: Persistence, Vectors, Redis Search, Licenses