RDBMS Project

This project is developed incrementally, starting from a minimal in-memory storage engine before layering query parsing and execution.

Done in refrence to pesapal's company idea to challenge junior devs to not only write code but think in systems design, architecture and thinking.

Carefully and precisely designed and developed by polymath kaila

---

Pipeline

SQL

• Parser (specific grammar first)
• AST (JoinSelect vs Select)
• Planner (AST → PlanNode)
• Executor (PlanNode execution)
• Storage

---

Query Planning

Queries are parsed into an AST(Abstract Syntax Tree) and then converted into explicit execution plans. JOIN queries are planned as nested-loop joins, while simple SELECT queries use index scans when available or fallback to table scans.

This separation mirrors real relational database engines.

---

Demo

$ python -m pyrel.repl.repl
db> CREATE TABLE users (id INT PRIMARY KEY, name TEXT);
OK
db> INSERT INTO users VALUES (1, "Alice");
OK
db> SELECT * FROM users WHERE id = 1;
[{'id': 1, 'name': 'Alice'}]