cynos-query 0.1.0

Query engine for Cynos in-memory database
Documentation

cynos-query

Query engine for Cynos in-memory database.

Overview

This crate provides the query execution engine including:

  • ast: Expression and predicate AST definitions
  • planner: Logical and physical query plans
  • optimizer: Query optimization passes
  • executor: Query execution operators
  • context: Execution context
  • plan_cache: Query plan caching for repeated queries

Features

  • #![no_std] compatible
  • Cost-based query optimization
  • Multiple join algorithms (hash join, merge join, nested loop)
  • Aggregate functions (COUNT, SUM, AVG, MIN, MAX)
  • Sort and limit operations
  • Plan caching for repeated queries

Query Operators

Operator Description
Scan Full table scan or index scan
Filter Row filtering with predicates
Project Column projection
Join Hash/Merge/Nested loop joins
Aggregate Group by with aggregations
Sort ORDER BY implementation
Limit LIMIT/OFFSET implementation

Optimization Passes

  • Predicate pushdown
  • Join reordering
  • Index selection
  • Projection pruning

License

Apache-2.0