nuo534202/pgcpp

How nuo534202/pgcpp works

pgcpp is a C++20 reimplementation of PostgreSQL’s database server and client tools. The main workflow is a client sending SQL to the server, which parses and analyzes it, rewrites views and security policies, plans it, executes it against access methods and storage, then returns results. The tree and README document broader administration, replication, and backup capabilities. Sampled source supports several runtime details, but not every subsystem’s wiring; links for unsampled stages are limited to the architecture and module roles evident in the repository.

Main entry points: postgres.cpp Client protocol · rewrite_handler.cpp Rewrite and RLS · exec_main.cpp Plan executor · psql_client.cpp psql client

Components 21

Server lifecycle

Server entry src/server/main.cpp
Postmaster src/server/postmaster.cpp
Cluster bootstrap src/server/bootstrap.cpp
Client protocol src/protocol/postgres.cpp

Query processing

Parse and analyze src/parser/analyze.cpp
Rewrite and RLS src/rewrite/rewrite_handler.cpp
Query planner src/optimizer/plan/planner.cpp
Plan executor src/executor/exec_main.cpp
SQL commands src/commands/tablecmds.cpp

Data and transactions

System catalog src/catalog/catalog.cpp
Heap and indexes src/access/heap/heapam.cpp
Buffer manager src/storage/buffer/bufmgr.cpp
Database files src/storage/smgr/md.cpp
Transactions and WAL src/transaction/xact.cpp

Operations and replication

Replication src/replication/logical.cpp
Apply worker src/replication/worker.cpp

Client tools

psql client src/tools/psql_client.cpp
Admin utilities tools/createdb/createdb.cpp
Dump and restore tools/pg_dump/pg_dump.cpp
Base backup tools/pg_basebackup/pg_basebackup.cpp

Other components

SQL user

Connections 20

SQL user → psql client: enters SQL
psql client → Client protocol: sends query
Server entry → Cluster bootstrap: dispatches bootstrap
Server entry → Postmaster: starts server
psql client → Client protocol: receives results
Client protocol → Parse and analyze: dispatches SQL
Parse and analyze → Rewrite and RLS: passes query
Rewrite and RLS → Query planner: passes rewritten query
Rewrite and RLS → System catalog: looks up views
Query planner → Plan executor: creates plan
Plan executor → Heap and indexes: runs scans
Plan executor → SQL commands: dispatches utility
Heap and indexes → Buffer manager: reads and writes pages
Buffer manager → Database files: reads and writes blocks
Transactions and WAL → System catalog: records transactional state
Transactions and WAL → Replication: supplies WAL
Replication → Apply worker: manages workers
Admin utilities → Client protocol: issues commands
Dump and restore → Client protocol: queries database
Base backup → Client protocol: requests backup

More C++ diagrams: openvpn/openvpn3 · mavlink/mavros · jasonrohrer/onelife · tranek/gasshooter · jmaczan/tiny-vllm

Drawn by GitDiagram on September 29, 2026 from the repository's file tree, README and source files. Read as Markdown ·