Files
five/_FiveSql2
CharlesKWON c84cde6175 perf(fivesql2): Go-native SqlIsAggName — drop per-row substring scan
B4 GROUP+HAVING profile showed SqlIsAggName at ~9% of CPU —
SqlEvalFunc checks it for every function in every row, and the
PRG body was two string allocations + a substring scan:
  RETURN ("," + c + ",") $ ("," + AGG_FUNCTIONS + ",")

Replace with a hash lookup against the existing aggFuncSet map
in hbrtl/sqlexpr.go (already populated for SqlExprHasAgg, same
AGG_FUNCTIONS list). Upper-casing skips the allocation when the
input is already upper, which it almost always is in practice.

Bench deltas (median of 3 steady runs, 1000 iters):
  B4_GROUP_HAVING 447 → 418 us  -6.5%
  B14_COUNT       252 → 235 us  -7%
  B15_CTE_WIN_JOIN 1595 → 1577 us  -1%
Other benches unchanged (no aggregate calls per row).

FiveSql2 43/43, Harbour compat 56/56.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-04-18 13:40:19 +09:00
..

FiveSql2 — SQL Engine for Harbour DBF/NTX/CDX

Pratt parser + SQL:1992-2023 full standard support Supports both NTX (Clipper) and CDX (FoxPro/ADS) indexes

Architecture

five_SQL("SELECT ...")
   │
   ├── TSqlLexer        Tokenizer
   ├── TSqlParser2      Pratt parser (data-driven operators)
   ├── TSqlExecutor     Query executor (Volcano model)
   │     ├── TSqlAlias  Central alias manager (no collisions)
   │     ├── TSqlIndex  NTX/CDX index optimization (auto-detect)
   │     ├── TSqlAgg    GROUP BY / aggregation
   │     ├── TSqlSort   ORDER BY / DISTINCT
   │     ├── TSqlDDL    CREATE/DROP/ALTER TABLE/INDEX
   │     └── TSqlTxn    BEGIN/COMMIT/ROLLBACK
   ├── TSqlExpr         AST nodes + expression evaluation
   └── TSqlFunc         60+ scalar functions

Build & Test

export PATH="/path/to/harbour-core/bin/linux/gcc:$PATH"
export HB_INSTALL_PREFIX="/path/to/harbour-core"

make          # Build all tests
make test     # Run all 157 tests
make bench    # Parser benchmark
make clean    # Clean

SQL Standard Coverage

Standard Features Tests
SQL:1992 SELECT, JOIN, GROUP BY, HAVING, Subquery, CASE, CAST 43
SQL:1999 CTE, Recursive CTE, Window Functions, MERGE 10
SQL:2003 SIMILAR TO, GROUPING SETS, LATERAL, Window frames 64
SQL:2008 FETCH/OFFSET, FOR UPDATE, Extended MERGE (incl.)
SQL:2016 JSON functions, LISTAGG (incl.)
SQL:2023 ANY_VALUE, GREATEST/LEAST, BOOL_AND/OR (incl.)
Challenge LeetCode-level complex queries 15
Extreme Production analytics stress tests 15

Adding New Operators

Edit TSqlParser2.prg, method InitInfixTables():

::hInfixTT[ TK_MYOP ] := { "<=>", 40, 41, ND_BIN }

One line. No structural changes needed.

Copyright (c) 2025-2026 Charles KWON (Charles KWON OhJun) Email: charleskwonohjun@gmail.com All rights reserved.