qail-core

The AST-native query builder — No SQL strings, no ORM magic, just type-safe expressions.

Why AST-Native?

QAIL builds queries as an Abstract Syntax Tree that compiles directly to database wire protocol. There's no SQL string generation step—safety is built into the design.

Installation

[!CAUTION] Alpha Software: QAIL is currently in alpha. While we strive for stability, the API is evolving to ensure it remains ergonomic and truly AST-native. Do not use in production environments yet.

[dependencies]
qail-core = "0.13.1"

Quick Start

use qail_core::{Qail, Operator};
use qail_core::ast::builders::*;

// Build a query as typed AST
let cmd = Qail::get("users")
    .columns([col("id"), col("name"), col("email")])
    .filter(eq("active", true))
    .order_by([("created_at", Desc)])
    .limit(10);

// Use with qail-pg driver
let rows = driver.fetch_all(&cmd).await?;

Ergonomic Expression Builders

use qail_core::ast::builders::*;

// Aggregates with FILTER
count_filter(vec![eq("status", "active")]).alias("active_users")

// Time expressions  
now_minus("24 hours")  // NOW() - INTERVAL '24 hours'

// CASE WHEN
case_when(gt("score", 80), text("pass"))
    .otherwise(text("fail"))
    .alias("result")

// Type casting
cast(col("amount"), "float8")

Features

• Type-safe expressions — Compile-time checked query building
• Ergonomic builders — count(), sum(), case_when(), now_minus()
• Full SQL support — CTEs, JOINs, DISTINCT ON, aggregates with FILTER
• JSON operators — ->, ->>, @>, ?
• Schema parser — Parse DDL into structured AST

Ecosystem

License

MIT

🤝 Contributing & Support

We welcome issue reports on GitHub! Please provide detailed descriptions to help us reproduce and fix the problem. We aim to address critical issues within 1-5 business days.