toondb-query

Query planning and execution engine for ToonDB.

Overview

toondb-query provides the query layer for ToonDB, featuring:

• Query Builder: Fluent API for constructing queries
• Query Optimizer: Cost-based optimization for efficient execution
• Projection Pushdown: Only read columns you need
• Filter Pushdown: Apply filters at storage layer
• TOON Output: Token-optimized format (40-66% fewer tokens than JSON)

Features

• SQL-like Queries: Familiar query patterns without SQL parsing overhead
• Path-based Access: O(|path|) resolution independent of data size
• Aggregations: COUNT, SUM, AVG, MIN, MAX with efficient execution
• Sorting & Pagination: ORDER BY, LIMIT, OFFSET support
• Join Support: Nested loop and hash joins

Installation

[dependencies]
toondb-query = "0.2.5"

Usage

Most users should use the high-level toondb crate:

use toondb::{Database, Query};

let db = Database::open("./my_data")?;

// Query with builder pattern
let results = db.query("users")
    .filter("age", ">", 21)
    .select(&["name", "email"])
    .order_by("name")
    .limit(10)
    .execute()?;

// Results in token-efficient TOON format
println!("{}", results.to_toon()); 
// users[3]{name,email}: Alice,alice@...|Bob,bob@...|Carol,carol@...

Query Execution Pipeline

┌──────────────┐
│    Query     │  User query (builder or path)
└──────┬───────┘
       │
       ▼
┌──────────────┐
│    Parse     │  Validate and normalize
└──────┬───────┘
       │
       ▼
┌──────────────┐
│   Optimize   │  Pushdown filters, projections
└──────┬───────┘
       │
       ▼
┌──────────────┐
│   Execute    │  Scan, filter, project, sort
└──────┬───────┘
       │
       ▼
┌──────────────┐
│   Format     │  TOON or JSON output
└──────────────┘

Crate Structure

License

Apache-2.0 - see LICENSE for details.