PHASE_8B_COMPLETED.md

Phase 8b: Enhanced Filtering & Key Optimization (Completed)

Status: Completed (2025-12-22)

This phase delivered advanced filtering capabilities and database optimizations for the Go/Bbolt target.

Delivered Features

1. Secondary Indexes

• Declaration: :- index(predicate/arity, field).
• Write Path: Automatically creates index_Pred_Field buckets and maintains Value:PrimaryKey entries.
• Read Path: Uses cursor.Seek() and bytes.HasPrefix() for optimized range scans when filters match indexed fields.

2. String Operations

• Case-Insensitive Equality: Field =@= "Value" maps to strings.EqualFold().
• Substring Match: contains(Field, "Sub") maps to strings.Contains().

3. List Membership

• Syntax: member(Field, [Val1, Val2]).
• Implementation: Generates efficient Go loops/slices to check membership.

4. Key Optimization

• Direct Lookup: Uses bucket.Get() for exact Primary Key matches.
• Prefix Scan: Uses cursor.Seek() for composite Primary Key prefix matches.
• Index Scan: Uses cursor.Seek() on Secondary Index buckets for indexed field matches.
• Fallback: Gracefully falls back to full bucket scan if no index/key optimization is possible.

Verification

• tests/test_go_index.pl: Verified index creation and write logic.
• tests/test_go_index_read.pl: Verified optimized read logic (Index Scan).
• tests/test_go_phase_8b.pl: Verified string ops and membership.