CharlesKWON
ce7593c50f
Extreme subquery stress bench (12 patterns spanning scalar-in-SELECT,
nested correlation, EXISTS, NOT IN, derived tables, self-joins, and
mixed combinations) exposed three weaknesses in the post-ROLLUP state:
1. EXISTS / NOT EXISTS evaluated the full subquery result per outer
row, even though it only needs to know whether any row matches.
2. EXISTS was routed through a separate code path that bypassed the
correlated-memoization cache from 2d90236.
3. The previous SubqueryCached identified each subquery node by
mutating slot 6 on the ast array via ASize — which interacted
badly with downstream code paths expecting the original shape
(derived-table queries panicked on ArrayPop after the ASize).
Fixes:
* EXISTS / NOT EXISTS now route through SubqueryCached the same way
ND_SUB in WHERE does, so correlated EXISTS predicates memoize on
outer free-variable values when the cardinality is low.
* The EXISTS handler plants `hQuery["limit"] := 1` on the subquery
before the first execution. EXISTS doesn't care about the rest
of the result rows, so dropping the scan cap saves full-scan
cost in the common case.
* A new early-termination branch in RunSelect's scan loop exits
the `WHILE !Eof()` as soon as aRows reaches nLimit, guarded by
the same "no ORDER BY / GROUP BY / agg / DISTINCT" precondition
(those need the full input). This is what makes the LIMIT 1
injection actually pay off — before, LIMIT was only applied via
ASize after the full materialized scan.
* SubqueryCached no longer mutates the parse tree. Instead of
ASize-ing the node and stashing cache metadata in slot 6, it
keeps a per-executor aSubCacheSlots list of
{xSubNode, {id, aFreeVars}} pairs and identifies nodes by
Harbour's reference-equality `==` on arrays. O(n) lookup in n =
number of distinct subqueries in the query, which is ≤ 4 or so
for all realistic queries, so the linear scan is free. Fixes the
derived-table ArrayPop panic.
Bench impact (emp=500, prod=100, ord=5k — subquery hell):
Pattern Before After Δ
───────────────────────────────────────────────────────
H3 Correlated EXISTS 13.3s 10.0s 1.3x
H7 Scalar-in-SELECT + JOIN 362ms 2ms 181x
H8 NOT EXISTS self-join 1.8s 900ms 2.0x
H11 Scalar + EXISTS + derived 13.7s 3.2s 4.3x
(H1, H2, H5, H6, H9, H10, H12 unchanged at 3–72ms)
H7's 181x is the scalar-in-SELECT-list memoization payoff — each
dept's revenue subquery used to run 100 times (once per SALES emp),
now runs once per distinct dept.
H3's 1.3x is the best we can do without semi-join lift: 500 outer
rows × 500 unique correlation keys = 500 cache misses, and the 375
rows whose correlation finds no match must scan the full ord table
to confirm emptiness. Fixing that needs the optimizer to rewrite
`WHERE EXISTS (SELECT 1 FROM ord WHERE ord.emp_id = e.id AND ...)`
into `WHERE e.id IN (SELECT DISTINCT emp_id FROM ord WHERE ...)`,
which is a real query-rewrite feature left for a follow-up.
Validation:
- FiveSql2 43/43
- Harbour compat 51/51
- go test ./... ALL PASS
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Five — Harbour + Go Fusion Language
Harbour PRG 코드를 네이티브 Go 바이너리로 컴파일하는 퓨전 언어.
30년간 축적된 Harbour/xBase 비즈니스 로직을 Go의 성능, 동시성, 크로스 플랫폼 위에서 실행합니다.
employees.prg → five build → employees (단일 실행파일, 18MB)
주요 특징
- Harbour 문법 100% 지원 (CLASS, CODE BLOCK, BEGIN SEQUENCE, ...)
- Go 네이티브 바이너리 출력 (CGo 없음, 순수 Go)
- DBF/NTX/CDX 데이터베이스 엔진 내장
- 479개 RTL 내장 함수
- FiveSql2: DBF 위에서 SQL:1999 쿼리 (43/43 테스트 통과)
- Goroutine/Channel 확장 (
GO BLOCK,CHANNEL) - @byref 참조 전달, mutable closure
- 대화형 디버거 (TUI/CLI)
빌드 방법
1. Go 설치
Five는 Go 1.21 이상이 필요합니다.
Linux/WSL:
# 이미 설치되어 있는지 확인
go version
# 없으면 설치
wget https://go.dev/dl/go1.22.5.linux-amd64.tar.gz
sudo rm -rf /usr/local/go
sudo tar -C /usr/local -xzf go1.22.5.linux-amd64.tar.gz
echo 'export PATH=$PATH:/usr/local/go/bin:$HOME/go/bin' >> ~/.bashrc
source ~/.bashrc
go version
macOS (Apple Silicon — M1/M2/M3/M4):
brew install go
# 또는 직접 다운로드:
wget https://go.dev/dl/go1.22.5.darwin-arm64.tar.gz
sudo tar -C /usr/local -xzf go1.22.5.darwin-arm64.tar.gz
echo 'export PATH=$PATH:/usr/local/go/bin:$HOME/go/bin' >> ~/.zshrc
source ~/.zshrc
macOS (Intel):
brew install go
# 또는 직접 다운로드:
wget https://go.dev/dl/go1.22.5.darwin-amd64.tar.gz
sudo tar -C /usr/local -xzf go1.22.5.darwin-amd64.tar.gz
echo 'export PATH=$PATH:/usr/local/go/bin:$HOME/go/bin' >> ~/.zshrc
source ~/.zshrc
Windows:
https://go.dev/dl/ 에서 .msi 설치
2. Five 컴파일러 빌드
git clone https://gitea.fivego.org/fivedev/five.git
cd five
go build -o five ./cmd/five
빌드 확인:
./five version
3. PRG 프로그램 컴파일 및 실행
단일 파일:
# 컴파일
./five build examples/hello.prg -o hello
# 실행
./hello
다중 파일 (FiveSql2 등):
./five build _FiveSql2/test/test_sql1999.prg _FiveSql2/src/*.prg -o test_sql
./test_sql
4. 테스트 실행
# Go 유닛 테스트
go test ./...
# FiveSql2 SQL 테스트 (43/43)
./five build _FiveSql2/test/test_sql1999.prg _FiveSql2/src/*.prg -o /tmp/test_sql
cd /tmp && ./test_sql
# Harbour 호환 테스트 (51/51)
./five build tests/compat_harbour.prg -o /tmp/test_compat
/tmp/test_compat
Five 명령어
five run <file.prg> 컴파일 후 즉시 실행
five build <file.prg> [-o out] 네이티브 바이너리 생성
five gen <file.prg> 생성된 Go 코드 출력 (디버깅용)
five debug <file.prg> 대화형 디버거 실행
five version 버전 정보
Hello World
// hello.prg
PROCEDURE Main()
? "Hello, Five!"
? "Date:", Date()
? "Time:", Time()
RETURN
./five build hello.prg -o hello && ./hello
SQL 예제
// sql_demo.prg
#include "FiveSqlDef.ch"
PROCEDURE Main()
// 테이블 생성
five_SQL("CREATE TABLE employees (id INTEGER, name CHAR(30), salary NUMERIC(12,2))")
// 데이터 삽입
five_SQL("INSERT INTO employees (id, name, salary) VALUES (1, 'Alice', 8000)")
five_SQL("INSERT INTO employees (id, name, salary) VALUES (2, 'Bob', 7000)")
// SQL 쿼리
LOCAL aR := five_SQL("SELECT name, salary FROM employees WHERE salary > 6000 ORDER BY salary DESC")
? "Results:", Len(aR[2]), "rows"
LOCAL i
FOR i := 1 TO Len(aR[2])
? " ", aR[2][i][1], aR[2][i][2]
NEXT
RETURN
./five build sql_demo.prg _FiveSql2/src/*.prg -o sql_demo && ./sql_demo
프로젝트 구조
five/
├── cmd/five/ Five CLI (main entry point)
├── compiler/ PRG → Go 컴파일러
│ ├── lexer/ 토크나이저
│ ├── parser/ 구문 분석기
│ ├── analyzer/ 의미 분석기
│ ├── gengo/ Go 코드 생성기
│ └── pp/ 전처리기 (#include, #define)
├── hbrt/ 런타임 (VM, Stack, Value, Class)
├── hbrtl/ RTL 표준 라이브러리 (479개 함수)
├── hbrdd/ RDD 데이터베이스 엔진
│ ├── dbf/ DBF 파일 드라이버
│ ├── ntx/ NTX 인덱스 드라이버
│ ├── cdx/ CDX 인덱스 드라이버
│ └── mem/ 메모리 RDD
├── _FiveSql2/ SQL:1999 엔진 (PRG)
│ ├── src/ SQL 엔진 소스 (14 파일, 10,458 LOC)
│ └── test/ SQL 테스트 스위트
├── tests/ 호환성 테스트
├── examples/ 예제 프로그램
└── docs/ 기술 문서
현재 상태
| 항목 | 수치 |
|---|---|
| Go 프로덕션 코드 | ~36,000 LOC |
| RTL 내장 함수 | 479개 |
| RDD 드라이버 | 4종 (DBF, NTX, CDX, Memory) |
| FiveSql2 테스트 | 43/43 (100%) |
| 호환 테스트 | 51/51 (100%) |
| Go 테스트 | ALL PASS |
라이선스
Copyright (c) 2025-2026 Charles KWON OhJun (charleskwonohjun@gmail.com) All rights reserved.