Two SQLite-style optimizations for RDD and SQL workloads:
1. FieldPos() O(1) column binding cache
Before: FieldPos(name) linear scan — O(n) per call with string
comparison. In SQL engines that call FieldPos per row per
column, this is hundreds of thousands of calls.
After: DBFArea builds a map[UPPER(name)]→pos on first lookup.
All subsequent lookups are O(1) hash. SQLite calls this
"column affinity binding" — positions resolved at prepare,
not per row.
Implementation:
- hbrdd/dbf/dbf.go: DBFArea.FieldPosCache(name) method
- hbrtl/procinfo.go: FieldPos RTL uses fieldPosCacher interface
- Lazy init: only pays for tables that get queried
2. hbrdd import auto-detection for function-call style PRGs
Before: compiler only added hbrdd import when PRG used xBase commands
(USE, SKIP, INDEX...). Pure function-call style like
`dbUseArea(.T.,,"t")`, `FieldPut(1, val)` was missed —
generated Go failed to compile ("undefined: hbrdd").
After: scanStmtsForXBase walks ExprStmt bodies too, detecting
CallExpr to any of the ~40 xBase RTL function names.
FIELD->NAME alias expressions also trigger the import.
Resolves: small PRGs that use only dbUseArea/FieldGet/FieldPut.
Benchmark notes (50k records):
Raw RDD scan: 7 ms (baseline)
FiveSql2 SELECT WHERE: 157 ms (unchanged — bottleneck is
not FieldPos, it's PRG-level
expression tree walk per row)
compat_harbour 51/51: PASS
FiveSql2 43/43: 100%
The FieldPos cache helps heavy field-name-based code paths but the
primary FiveSql2 bottleneck is the PRG interpreter walking expression
ASTs per row (needs bytecode compilation to close the gap).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
1. SOFTSEEK: use idx.CurRecNo() for positioning (was checking recNo > 0)
- SEEK with SET SOFTSEEK ON now positions at next higher key
- SEEK command reads SET SOFTSEEK at runtime (was compile-time only)
- rtlDbSeek defaults to GetSetSoftSeek() when no explicit param
2. SET DELETED ON + INDEX: SkipIndexed skips deleted records
- GoTopIndexed: skip deleted record at top position
- SkipIndexed: inner loop continues past deleted records
3. Compound key (CITY+NAME): field name TrimSpace before lookup
- evalKeyExprInner: TrimSpace on fieldName after FIELD-> strip
- Fixed "CITY " != "CITY" mismatch from + operator splitting
4. SET INDEX TO filename: treated as string, not variable
- gengo uses exprToString for SET INDEX TO (was emitExpr)
- Prevents identifier being resolved as local variable
5. hasXBaseCommands: recursive scan into nested blocks
- BEGIN SEQUENCE, IF, FOR, DO WHILE, SWITCH bodies now scanned
- Fixes missing hbrdd import for DB commands inside blocks
Thorough test: 77 items (14 sections) covering exact/partial/soft seek,
SET DELETED, duplicate keys, numeric keys, compound keys, empty/single
table, state consistency, order switching, full traversal — all identical.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
