Compositional Acset Comparison

Compositional ACSet Comparison Skill

Trit: 0 (ERGODIC - Coordinator) Color: #26D826 (Green) Domain: Compositional algorithm/data analysis via algebraic databases

Homoiconic Insight

In self-hosted Lisps, the boundary between data structures and algorithms dissolves:

• Code is data, data is code (homoiconicity)
• Evaluation time is phase-scoped (RED/BLUE/GREEN gadgets)
• Entanglement avoided by leaving phases open until explicitly closed
• Compositional structure preserved across algorithm ↔ data boundary

Overview

Compare data structures and their properties (density/sparsity, dynamic/static, versioning strategies) using the richness afforded by ACSets. Uses Gay.jl-aided superrandom walks for deterministic exploration of comparison dimensions.

Canonical Triads

schema-validation (-1) ⊗ compositional-acset-comparison (0) ⊗ gay-mcp (+1) = 0 ✓  [Property Analysis]
three-match (-1) ⊗ compositional-acset-comparison (0) ⊗ koopman-generator (+1) = 0 ✓  [Dynamic Traversal]
temporal-coalgebra (-1) ⊗ compositional-acset-comparison (0) ⊗ oapply-colimit (+1) = 0 ✓  [Versioning]
polyglot-spi (-1) ⊗ compositional-acset-comparison (0) ⊗ gay-mcp (+1) = 0 ✓  [Homoiconic Interop]

Golden Thread Walk Dimensions

Each dimension is explored via φ-angle (137.508°) golden spiral for maximal dispersion:

Comparison Matrix: DuckDB vs LanceDB

Dimension 1: Storage Hierarchy (#EE2B2B)

DuckDB                          LanceDB
──────                          ───────
Table                           Database
  └─RowGroup (122K rows)          └─Table
      └─Column                        └─Manifest (version)
          └─Segment                       └─Fragment
              └─Block                         └─Column
                                                  └─VectorColumn

ACSet Morphism Depth:

• DuckDB: 4 levels (Table→RowGroup→Column→Segment)
• LanceDB: 5 levels (Database→Table→Manifest→Fragment→Column)

Dimension 2: Density/Sparsity (#2BEE64)

Density Formula:

density(acset, obj) = nparts(acset, obj) / theoretical_max(acset, obj)
# DuckDB Segment: ~2048 rows per vector batch
# LanceDB Fragment: variable, optimized for vector search

Dimension 3: Dynamic/Static (#9D2BEE)

State Machine:

DuckDB Segment: TRANSIENT ⟷ PERSISTENT (bidirectional)
LanceDB Manifest: V1 → V2 → V3 → ... (append-only chain)

Dimension 4: Versioning Strategy (#EED52B) ⭐ Lance SDK 1.0.0

Critical Update (December 15, 2025): Lance SDK adopts SemVer 1.0.0

Key Insight: Breaking SDK changes will NOT invalidate existing Lance data.

# ACSet representation of versioning strategies
@present SchVersioning(FreeSchema) begin
  SDKVersion::Ob      # SemVer (1.0.0)
  FileFormat::Ob      # Binary compat (2.1)
  TableFormat::Ob     # Feature flags
  NamespaceSpec::Ob   # Per-operation
  
  # Morphisms: SDK ≠ Format
  sdk_file::Hom(SDKVersion, FileFormat)      # Many-to-one
  file_table::Hom(FileFormat, TableFormat)   # Independent
  table_ns::Hom(TableFormat, NamespaceSpec)  # Independent
end

DuckDB Versioning:

• Temporal tables via VERSION AT
• Extension versioning separate from core

Dimension 5: Traversal Patterns (#2BCDEE)

ACSet Incident Queries:

# DuckDB: Find all segments in a column
incident(duckdb_acset, col_id, :column)

# LanceDB: Find all centroids for an index
incident(lancedb_acset, idx_id, :partition_index) |>
  flatmap(p -> incident(lancedb_acset, p, :centroid_partition))

Dimension 6: Index Structures (#EE2B94)

ACSet Index Representation:

# LanceDB vector index hierarchy
VectorIndex → Partition → Centroid
    ↓
index_column → VectorColumn → Column

Dimension 7: Compression (#5BEE2B)

Dimension 8: Query Model (#332BEE)

Dimension 9: Embedding Support (#EE6C2B)

Dimension 10: Interoperability (#2BEEA5)

Cross-Language (from ACSets Intertypes):

# Generate interoperable types
generate_module(DuckDBACSet, [PydanticTarget, JacksonTarget])
generate_module(LanceDBACSet, [PydanticTarget, JacksonTarget])

Dimension 11: Concurrency (#DE2BEE)

Dimension 12: Memory Model (#C5EE2B)

Interleaved 3-Stream Comparison

Using GF(3) conservation for balanced parallel analysis:

Stream 1 (Blue, -1): Validation/Constraints
  #31945E → #B3DA86 → #8810F2 → #2F5194 → #2452AA → #245FB4

Stream 2 (Green, 0): Coordination/Transport
  #6D59D2 → #9E2981 → #72E24F → #31C5B4 → #C04DDD → #1C8EEE

Stream 3 (Red, +1): Generation/Composition
  #E22FA7 → #E812C8 → #6F68E6 → #25D840 → #DA387F → #A82358

Crystal Family Analogy

Data structures map to crystal symmetry:

Hierarchical Control Palette

Powers PCT cascade for harmonious comparison:

Level 5 (Program): "Compare DuckDB vs LanceDB"
    ↓ sets reference for
Level 4 (Transition): Dimension sequence [30° steps]
    ↓ sets reference for
Level 3 (Configuration): Property relationships
    ↓ sets reference for
Level 2 (Sensation): Individual metrics
    ↓ sets reference for
Level 1 (Intensity): Numeric values

Colors: #B322C0 → #D5268C → #DC3946 → #DF884A → #E0D551 → #A3E04E

XY Model Phenomenology

At τ=0.5 (ordered phase, τ < τ_c=0.893):

• Smooth field, defects bound in pairs
• High valence, disentangled
• Antivortex at (4,3): #C33567

Interpretation: Both DuckDB and LanceDB are in "ordered phase" - mature, production-ready systems with well-defined structures.

Usage

using ACSets, Catlab

# Load both schemas
include("DuckDBACSet.jl")
include("LanceDBACSet.jl")

# Compare morphism structures
compare_schemas(SchDuckDB, SchLanceDB)

# Analyze density
density_analysis = map([SchDuckDB, SchLanceDB]) do sch
  Dict(ob => sparsity_metric(sch, ob) for ob in obs(sch))
end

# Traverse with Gay.jl colors
for (i, dimension) in enumerate(DIMENSIONS)
  color = gay_color_at(1000000, i)
  analyze_dimension(dimension, color)
end

Skill Files

Ghrist Persistent Homology Integration

Based on de Silva & Ghrist "Coverage in Sensor Networks via Persistent Homology":

AM Radio Coverage Analogy:

• Radio stations = Schema objects (Table, Column, etc.)
• Coverage radius = Morphism composability range
• Signal overlap = Translatable concepts between schemas
• Dead zones = Irreversible information loss

Betti Numbers for Schemas:

• β₀: Connected components (isolated subsystems)
• β₁: Coverage holes (information flow gaps)
• β₂: Enclosed voids (unreachable regions)

Persistent Holes (never die):

• 🔴 parent_manifest: Temporal irreversibility (version chain)
• 🔴 source_column: Semantic irreversibility (embedding loss)

Geometric Morphism Analysis

For presheaf topoi PSh(SchDuckDB) and PSh(SchLanceDB):

Essential Image (lossless translation):

• Table ↔ Table ✓
• Column ↔ Column ✓

Partial Coverage (lossy translation):

• RowGroup ~ Fragment
• VectorColumn → Column (loses vector semantics)

Dead Zones (no translation):

• Segment → ??? (DuckDB-only)
• Manifest ← ??? (LanceDB-only)
• VectorIndex ← ??? (LanceDB-only)

References

• de Silva & Ghrist, Coverage via Persistent Homology
• Lance SDK 1.0.0 Announcement (December 15, 2025)
• DuckDB Architecture
• ACSets.jl Documentation
• StructuredDecompositions.jl
• Gay.jl Deterministic Colors