Documentation
3. Concepts
Developer-focused documentation with concepts, function details, examples, outputs and SQL comparisons.
What is RelPyDB?
RelPyDB is an in-memory relational object library. It lets Python code define tables, constraints and queries without running a database server.
| Relational idea | RelPyDB object | SQL equivalent |
|---|---|---|
| Database | RelPy() | Database/schema |
| Table | create_table("users") | CREATE TABLE users (...) |
| Column | add_column(...) | Column definition |
| Row | Python dict | Record / tuple |
| Query | db.query(...) | SELECT |
When to use it
- Learning relational modeling in Python.
- Building small in-memory relational objects.
- Testing domain logic without setting up SQL.
- Exporting data to JSON, pandas, NumPy or SQL insert scripts.
- Keeping small local data objects with optional encrypted columns.
When not to use it
RelPyDB is not PostgreSQL, SQLite or DuckDB. It is not designed for concurrent multi-user workloads, large production datasets or transactional database guarantees.