libdplyr

A Rust-based transpiler that converts R dplyr syntax to SQL queries.

Overview

libdplyr enables R users to write database queries using familiar dplyr syntax and converts them to efficient SQL for execution. It supports multiple SQL dialects (PostgreSQL, MySQL, SQLite, DuckDB) for use across various database environments.

✨ Key Features

• dplyr Syntax Support: Full support for select(), filter(), mutate(), arrange(), group_by(), summarise()
• Pipeline Operations: Chain operations using the %>% pipe operator
• Multiple Dialects: PostgreSQL, MySQL, SQLite, DuckDB
• Performance: High-performance Rust implementation
• Dual Mode: Use as a Rust library or standalone CLI tool

🚀 Quick Start

Linux/macOS:

curl -sSL https://raw.githubusercontent.com/mrchypark/libdplyr/main/install.sh | bash

Windows (PowerShell):

Irm https://raw.githubusercontent.com/mrchypark/libdplyr/main/install.ps1 | iex

Try it out:

echo "select(name, age) %>% filter(age > 18)" | libdplyr --pretty

Note: For detailed installation options, troubleshooting, and platform support, see the Installation Guide.

Usage

As a CLI Tool

The most efficient way to use libdplyr is through stdin/stdout pipelines:

# Basic usage
echo "select(name, age) %>% filter(age > 18)" | libdplyr

# Specify dialect (postgres, mysql, sqlite, duckdb)
echo "select(name)" | libdplyr --dialect mysql

# Output formatting
echo "select(name)" | libdplyr --pretty
echo "select(name)" | libdplyr --json
echo "select(name)" | libdplyr --compact

As a Rust Library

use libdplyr::{Transpiler, PostgreSqlDialect};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let transpiler = Transpiler::new(Box::new(PostgreSqlDialect::new()));
    let dplyr_code = "select(name, age) %>% filter(age > 18)";
    
    let sql = transpiler.transpile(dplyr_code)?;
    println!("{}", sql);
    Ok(())
}

📋 Supported Functions

libdplyr supports a wide range of dplyr verbs and R functions.

Core Verbs

Function	Description	Example
select()	Select/rename columns	select(id, name)
filter()	Filter rows	filter(age > 18)
mutate()	Create/modify columns	mutate(total = price * qty)
rename()	Rename columns	rename(new = old)
arrange()	Sort rows	arrange(desc(date))
group_by()	Group rows	group_by(dept)
summarise()	Aggregate data	summarise(avg = mean(val))
*_join()	Joins (inner, left, etc.)	left_join(other, by="id")
Set Ops	union, intersect, setdiff	union(other)

Helper Functions

• Aggregation: mean, sum, min, max, n, count, median, mode
• Window: row_number, rank, lead, lag, ntile
• Math: abs, sqrt, round, floor, log, exp
• String: tolower, toupper, substr, trimws
• Logic: ifelse, is.na, coalesce

Examples

PostgreSQL

let transpiler = Transpiler::new(Box::new(PostgreSqlDialect::new()));
let sql = transpiler.transpile("select(name) %>% filter(age > 18)")?;
// SELECT "name" FROM "data" WHERE "age" > 18

Complex Pipeline

let code = r#"
    select(dept, salary) %>%
    filter(salary > 50000) %>%
    group_by(dept) %>%
    summarise(avg_sal = mean(salary)) %>%
    arrange(desc(avg_sal))
"#;

Error Handling & Troubleshooting

libdplyr provides detailed error codes:

• Exit 0: Success
• Exit 4: Validation Error (syntax issues)
• Exit 5: Transpilation Error (generation failed)

Debug Mode:

libdplyr --verbose --debug

For more troubleshooting details, see INSTALL.md.

Performance

libdplyr is optimized for speed using Rust's zero-cost abstractions. Run benchmarks:

cargo bench

Development

# Setup
git clone https://github.com/mrchypark/libdplyr.git
cd libdplyr
cargo build

# Test
cargo test

Support

• Documentation: docs.rs/libdplyr
• Installation: INSTALL.md
• Issues: GitHub Issues

License

MIT License. See LICENSE.