The Semantic Layer Explosion: Why Everyone Is Building One and Why Most Do Not Solve the Problem

Every data tool now claims semantic layer capabilities. But most implementations create new silos rather than solving the consistency problem. Learn what separates effective semantic layers from marketing checkboxes.

7 min read·

Five years ago, semantic layers were a niche concept familiar mainly to data architects. Today, every data warehouse, BI tool, and analytics platform claims semantic layer capabilities. This proliferation should be good news - finally, the industry recognizes that business context matters for analytics accuracy.

But the reality is more complicated. Most of these semantic layers create new silos rather than solving the consistency problem they claim to address.

The Semantic Layer Moment

Why Now

Several forces converged to make semantic layers urgent:

AI requirements: Generative AI needs business context to produce accurate answers. Without semantic layers, AI hallucinates.

Self-service failures: Years of self-service BI produced inconsistent metrics and eroded trust. Organizations need controlled consistency.

Data mesh influence: Data mesh concepts elevated semantic clarity as essential for decentralized data ownership.

Cloud data growth: As data moved to cloud warehouses, the need for business abstraction became acute.

The market recognized that raw data is not enough - meaning must be captured.

The Vendor Response

Every category of vendor has responded:

Data warehouses: Snowflake, Databricks, BigQuery all added semantic capabilities BI tools: Looker, Tableau, Power BI enhanced their modeling features Metrics platforms: dbt, Metriql, Cube emerged as dedicated solutions AI platforms: Every AI analytics vendor claims semantic foundations

The checkbox is checked everywhere. But checking a box is not the same as solving the problem.

The Fragmentation Problem

The Scenario

Consider a typical enterprise:

  • Snowflake with its semantic layer capabilities
  • Looker with LookML
  • Power BI with its data model
  • AI analytics platform with its own metric definitions

Each has a "semantic layer." But do they share definitions?

Usually not.

Why Fragmentation Happens

Tool-centric design: Each vendor builds for their tool, not for enterprise consistency

Different philosophies: Vendors disagree on where semantic logic belongs

Lock-in incentives: Portable definitions reduce switching costs for customers

Technical barriers: Making semantic layers interoperate is genuinely hard

The result: multiple semantic layers that do not talk to each other.

The Ironic Outcome

Organizations adopting multiple semantic layers end up with:

  • Revenue defined one way in the warehouse semantic layer
  • Revenue defined differently in the BI semantic layer
  • Revenue defined yet another way in the AI analytics layer

This is exactly the problem semantic layers were supposed to solve - now with more complexity.

Evaluating Semantic Layers

The Unity Test

The fundamental question: Does this semantic layer unify or fragment?

Signs of unity:

  • Can serve multiple consumption tools
  • Becomes the single source of metric definitions
  • Definitions are portable, not locked in
  • Designed for organization-wide use

Signs of fragmentation:

  • Only serves one tool
  • Creates another definition silo
  • Proprietary format with no portability
  • Designed for tool adoption, not organizational consistency

Unity is the value proposition. Fragmentation is the failure mode.

Categories of Semantic Layers

Different types serve different purposes:

Universal semantic layers: Designed to serve all downstream tools

  • Pros: True consistency, vendor independence
  • Cons: Additional layer to manage, integration complexity
  • Examples: Cube, AtScale, certain custom implementations

Platform semantic layers: Embedded in data platforms

  • Pros: Close to data, potentially simpler
  • Cons: May not reach all tools, platform lock-in
  • Examples: Snowflake views, Databricks Unity Catalog

BI tool semantic layers: Native to visualization tools

  • Pros: Tight tool integration, familiar to users
  • Cons: Limited to that tool, creates silos
  • Examples: LookML, Power BI Data Model

AI-native semantic layers: Built for AI analytics

  • Pros: Optimized for AI context needs
  • Cons: May not serve traditional BI
  • Examples: Various AI analytics platforms

The Right Choice

The right semantic layer depends on your situation:

If you have one BI tool: Its native semantic layer may suffice If you have multiple tools: A universal layer is likely needed If AI analytics is priority: Ensure the layer serves AI context needs If you have complex governance: Look for strong governance integration

No single answer fits all situations.

The Architecture Question

Where Should Semantic Logic Live?

Vendors disagree fundamentally:

In the warehouse: Close to data, enforced at source

  • Argument: Single source of truth at the data level
  • Counter: Warehouses are not designed for rich business context

In a dedicated layer: Separate semantic platform

  • Argument: Purpose-built for semantic concerns
  • Counter: Another layer to manage and integrate

In BI tools: Where users work

  • Argument: Familiar, integrated experience
  • Counter: Creates tool silos

In AI platforms: Where context is consumed

  • Argument: Optimized for AI needs
  • Counter: Does not serve traditional BI

The honest answer: there is no industry consensus. The best architecture depends on your specific tools, teams, and requirements.

Codd AI's Approach

Codd AI takes a pragmatic position:

Context-first design: Built from the ground up for the rich context AI needs

Integration philosophy: Works with your existing semantic investments rather than replacing them

Governance integration: Respects and extends your governance models

Practical focus: Solves the actual problem of accurate AI analytics

Rather than claiming to be the universal semantic layer for all purposes, Codd AI focuses on being excellent for AI analytics while integrating with broader semantic infrastructure.

Making Progress Despite Fragmentation

Strategic Principles

Start with the problem, not the tool: Define what consistency you need before selecting solutions

Accept imperfection: Perfect semantic unity may not be achievable; aim for "good enough"

Prioritize high-value metrics: Ensure critical metrics are consistent everywhere they appear

Plan for evolution: The landscape is changing; design for adaptability

Practical Steps

1. Inventory current state

  • What semantic capabilities exist?
  • Where are definitions inconsistent?
  • Which inconsistencies matter most?

2. Define target architecture

  • Which tools need consistent definitions?
  • Where will the authoritative definitions live?
  • How will definitions flow to consumption points?

3. Implement incrementally

  • Start with highest-value metrics
  • Prove value before expanding
  • Build organizational support through success

4. Establish governance

  • Who owns metric definitions?
  • How are changes approved?
  • How is consistency enforced?

What to Avoid

The checkbox trap: Adopting semantic features because they exist, not because they solve your problem

The perfect architecture pursuit: Waiting for the perfect solution while inconsistency persists

The vendor lock-in slide: Building deeply on proprietary semantic formats without exit strategies

The governance vacuum: Deploying semantic layers without processes to maintain them

The Future of Semantic Layers

Standardization pressure: Organizations will demand portability, pushing vendors toward interoperability

AI as the forcing function: AI accuracy requirements will drive semantic investment

Governance convergence: Semantic layers will integrate more deeply with data governance

Consolidation: The crowded vendor landscape will consolidate

Implications

For organizations, these trends suggest:

Invest in foundations: Regardless of which tools win, semantic foundations will matter Maintain flexibility: Avoid deep lock-in to any single semantic approach Build skills: Semantic modeling skills will remain valuable Watch the market: The landscape is evolving rapidly

Conclusion

The semantic layer explosion is both opportunity and risk. The opportunity is that the industry finally recognizes the importance of business context for analytics accuracy. The risk is that fragmented implementation recreates the consistency problems semantic layers are meant to solve.

Organizations that approach semantic layers strategically - focusing on unity over checkboxes, solving real problems over adopting features - will capture the benefits while avoiding the pitfalls.

The question is not whether you need semantic capabilities. The question is whether your semantic approach actually delivers consistent, governed, accessible business context - or just adds another layer of complexity.

Questions

AI analytics requires business context to be accurate, and semantic layers provide that context. Every vendor recognizes this need. However, most build semantic layers to serve their own tools rather than to unify definitions across the organization.

Related