query-planner

Google Cloud Spanner Query Planner Visualizer

build your own query planner

An eBPF based query planning tracer for PostgreSQL

Run the PostgreSQL Explain Visualizer 2 (pev2) from the command line.

Context Runtime — a database query planner for LLM context. Decides what a model sees before it answers; plans it, runs it through reused substrate, and learns from the outcome.

A tiny relational database written in Go

A minimal educational relational database management system (RDBMS) implemented in Java 17. The project demonstrates a custom SQL processing pipeline, including lexer, parser, semantic analysis, query planning, optimization, and execution. It features a storage engine with heap pages, a buffer pool, and supports indexing using B-trees and Hash

Hypothetical IVFFlat indexes for pgvector: test planner choices in EXPLAIN without building a physical index

From-scratch database systems lab with SQL parser, slotted pages, WAL recovery, direct paged B+Tree index reads, query planner, and guided Workbench UI.

openCypher front-end in Rust. Lex · parse · sema · plan · optimize · cost. Ships an MCP server (cypher-mcp). Storage-agnostic. v0.10 shipped.

Show all plans considered by the optimizer

実行計画とインデックスを原理から理解するために、Go で RDBMS を一から作る。触ったページ数を全レイヤで計測する。

A columnar analytical database engine built from first principles in Rust: encodings, a segment format with pushdown, a hand-written SQL parser and a logical planner.

A relational database engine written from scratch: slotted-page storage, an on-disk B+ tree, a SQL parser, a rule-based planner and a volcano executor.

Lint Postgres EXPLAIN ANALYZE plans for slow-query anti-patterns: seq scans on filtered big tables, hash joins spilling to disk, nested loops on too many outer rows, sort spilling, planner row-estimate skew. Reads JSON or text plans.

Model-driven data layer for industrial asset data: a typed DSL compiling to a relational schema, a Gorilla-encoded time series store, and a planner that pushes filters down and batches joins across both

MiniDB: A compact relational database engine with a SQL shell, persistent storage, indexes, transactions, and WAL support.

Rogue planets are starless planets, scientifically adrift in the cosmic dark alone

Small SQL query engine written from scratch in Go, with a volcano execution model, hash joins, aggregation, three-valued NULL semantics, and SQLite differential testing.

A mini SQL database written from scratch in Rust for learning — pager, B+Tree, SQL parser, cost-free query planner, transactions, and an HTTP server. Standard library only, no crates.