Custom SQL Interpreter & Engine

Reconstructing a relational database as a learning project in Rust

Check it out

1. Clone repository and build binary using cargo build --release

2. Use in one of two ways

   a. Using cli arg: pathto/binary "SQL query"

   b. Using the interactive shell. Start it by executing the binary without cli args. Quit it by submitting the character 'q'.

What r_sql can do

1. Parse simple queries (SELECT (WHERE, AND), INSERT INTO, CREATE TABLE, CREATE INDEX)
2. Handle simple reads/writes
3. Use indices on columns for improved read performance

What r_sql cannot (yet) do

1. More complex queries, including subqueries, SORT BY, ORDER BY, LIMIT, functions like COUNT() and the like
2. Constraints, such as NOT NULL, DEFAULT _, UNIQUE, ..

TODOS

• indices: allow a leaf to point to multiple data pages
• basic constraints, such as NOT NULL, DEFAULT, UNIQUE
• implement WAL
• implement more of the common SQL syntax, such as DROP and UPDATE and DELETE

Limitations

I consciously chose to not implement logic for the following

1. I don't handle the case that a single record exceeds the size of a datapage
2. I don't implement DB metadata like users or privileges