docs: project documentation

README.md

@@ -1,7 +1,113 @@
 # MiniSQL
 
-## Installation
+## Project Structure
+- `client` - REPL client for connecting to the server
+- `server` - MiniSQL server
+- `minisql` - SQL AST interpreter
+- `parser` - SQL parser
+- `proto` - Implementation of subset of PostgreSQL protocol
 
+## Requirements
+- Rust + Cargo with version **>= 1.74.0** (using `impl` in return statements)
+- Optional: `psql` cli for testing the server
+
+# Usage
+
+## Running the server
+```bash
+cargo run -p server -- [OPTIONS] --file <FILE>
 ```
-git clone git@gitlab.fi.muni.cz:x433485/minisql.git
+```
+Options:
+  -a, --address <ADDRESS>  IP address for the server to listen on [default: 127.0.0.1]
+  -p, --port <PORT>        Port for the server to listen on [default: 5432]
+  -f, --file <FILE>        Path to the data file
+  -h, --help               Print help
+```
+
+This will start the server listening on `<ADDRESS>:<PORT>` and load the state from `<FILE>`.
+If the `<FILE>` does not exist, it will be created.
+
+### Demo Database
+A database with demo data is available in `demo.json`. To run the server with this database, use:
+```bash
+cargo run -p server -- --file demo.json
+```
+
+This database contains two tables:
+- Table `users` with columns `id`, `name`, `surname`, `email`
+- Table `cars` with columns `id`, `vid`, `brand`, `model`, `year`
+
+## Running the client
+```bash
+cargo run -p client -- [OPTIONS]
+```
+```
+Options:
+  -p, --port <PORT>          Port number of the server [default: 5432]
+      --host <HOST>          Host name or IP address of the server [default: 127.0.0.1]
+      --username <USERNAME>  User name [default: "minisql user"]
+  -h, --help                 Print help
+```
+
+This will start a REPL client that connects to the server at `<HOST>:<PORT>` and authorizes with `<USERNAME>`.
+SQL queries can be entered line by line. The client will print the result of each query.
+
+To exit the REPL client, enter `exit` or `quit`.
+
+# Features
+- 
+- SQL must be on single line, in **UPPERCASE** and end with `;`, as it should be
+- Supported operations: `CREATE TABLE`, `CREATE INDEX`, `SELECT`, `INSERT`, `DELETE`
+- Supported data types: `UUID`, `STRING`, `INT`, `NUMBER`
+- Supported subset of PostgreSQL protocol, without authentication and simple query flow
+
+## Operations
+
+### `CREATE TABLE`
+- Every table requires one column with type `UUID` as `PRIMARY KEY`
+
+```sql
+CREATE TABLE <TableName> (<ColumnName> <DataType>, ...);
+```
+
+### `CREATE INDEX`
+- Indexing is not supported for the `NUMBER` data type
+
+```sql
+CREATE INDEX <IndexName> ON <TableName> (<ColumnName>);
+```
+
+### `SELECT`
+- `WHERE` clause is optional and only equality is supported
+- All columns can be selected with `*`
+
+```sql
+SELECT <ColumnName>, ... FROM <TableName> [WHERE <ColumnName> = <Value>];
+```
+
+### `INSERT`
+
+```sql
+INSERT INTO <TableName> (<ColumnName>, ...) VALUES (<Value>, ...);
+```
+
+### `DELETE`
+- `WHERE` clause is optional and only equality is supported
+
+```sql
+DELETE FROM <TableName> [WHERE <ColumnName> = <Value>];
+```
+
+## Data Types
+- `UUID` - special integer prefixed with `u`, e.g. `u12345`
+- `STRING` - string enclosed in double quotes, e.g. `"Hello World"`
+- `INT` - integer, e.g. `12345`
+- `NUMBER` - floating point number, e.g. `123.45`
+
+## Testing with `psql`
+Thanks to the subset of PostgreSQL protocol implemented in `proto`, the server can be tested with `psql`,
+which offers REPL client similar to the `client` crate:
+```bash
+psql -h <HOST> -p <PORT>
 ```