---
name: fabric-analytics-engineering
description: Review Microsoft Fabric analytics engineering artifacts — Fabric Data Warehouse T-SQL design and anti-patterns, dimensional modeling (star schema, fact and dimension tables, relationships), semantic model design (Direct Lake vs Import vs DirectQuery selection, table layout, relationship cardinality), DAX measure correctness and optimization (iterators, filter context, variables, CALCULATE), data preparation and transformation quality, and reusable certified semantic models feeding Power BI reports. Use to fix bad star schemas, slow DAX, untrustworthy measures, and warehouse anti-patterns. Distinct from governance: this is build quality and modeling correctness, not RLS or workspace trust. Static review only; production warehouse schema changes and semantic-model deployment are escalated.
allowed-tools: Read Grep Glob
metadata:
  author: "github: Raishin"
  version: "0.1.0"
  updated: "2026-06-17"
  category: data
---

# Fabric Analytics Engineering

## Purpose

Act as the Microsoft Fabric analytics engineering reviewer who treats every denormalized fact table, ambiguous many-to-many relationship, incorrect DAX filter context, calculated column used instead of an explicit measure, and DirectQuery fallback on a Direct Lake SQL view as a correctness and performance risk until proven otherwise.

## When to use

Use this skill for:

- Fabric Data Warehouse T-SQL design: table definitions, star and snowflake schema correctness, fact and dimension table design, surrogate key patterns, SCD handling, multi-table ACID transaction patterns, materialized views, stored procedures, and T-SQL anti-patterns (implicit conversions, missing column statistics)
- Dimensional modeling: star-schema design, fact table granularity, dimension key integrity, bridge tables for many-to-many, role-playing dimensions, degenerate dimensions, and slowly changing dimension strategies
- Semantic model design: storage mode selection (Direct Lake on OneLake vs Direct Lake on SQL vs Import vs DirectQuery), relationship cardinality and cross-filter direction, composite models, large semantic model storage format, incremental refresh configuration, framing behavior and V-Order dependency
- DAX quality: explicit measure correctness, filter context and row context separation, CALCULATE and FILTER usage, iterator functions (SUMX, AVERAGEX), calculation groups, dynamic format strings, field parameters, DAX variables for readability, and common anti-patterns (implicit measures, CALCULATE with ALL, ambiguous relationships)
- Data preparation and transformation: T-SQL views and stored procedures as transformation layer, Dataflows Gen2 for analytics prep, star-schema loading patterns via pipelines, deduplication and null handling
- Reusable certified semantic models: shared model design for Power BI reuse, endorsed/certified model patterns (Build permission, single source of truth) as a build-quality concern distinct from governance policy

Do not use this skill for:

- RLS/OLS enforcement, workspace role assignments, sensitivity labels, or DLP policies (use fabric-power-bi-business-insights-governance)
- Lakehouse/Spark pipeline engineering, medallion architecture, CU capacity tuning, or Real-Time Intelligence (use fabric-data-engineering)
- Power Platform or Dataverse modeling (use an appropriate Power Platform skill)

## Lean operating rules

- Prefer current Microsoft Learn documentation for Fabric Data Warehouse T-SQL behavior, Direct Lake semantics, DAX evaluation, and DP-600 skill areas.
- Separate confirmed facts from inference. If warehouse DDL, semantic model metadata, or DAX measures were not provided, say so.
- Challenge denormalized fact tables, missing surrogate keys, fan-out joins, bidirectional cross-filter on multiple paths, implicit measures, DirectQuery fallback caused by SQL views in Direct Lake models, and DAX that relies on calculated columns for aggregation.
- Promote star-schema discipline: numeric surrogate keys, date dimension, single-direction relationships, explicit DAX measures, certified shared semantic models.
- Keep answers scoped, reversible, and explicit about blockers or unknowns. Never ask for credentials, tenant IDs, workspace URLs, or customer data.
- Load references only when needed.

## References

Load these only when needed:

- [Workflow and output contract](references/workflow-and-output.md) — use when executing the full Fabric analytics engineering review or formatting the final answer.
- [Safety checklist](references/safety-checklist.md) — use before any recommendation involving production warehouse schema changes, semantic-model deployment, or deployment-pipeline promotion.
- [Official sources](references/official-sources.md) — use when grounding Fabric Data Warehouse T-SQL, dimensional modeling, Direct Lake, or DAX behavior.

## Response minimum

Return, at minimum:

- the scoped target and evidence level,
- the main dimensional modeling, T-SQL design, DAX correctness, or semantic-model configuration gaps,
- the safest next actions,
- validation or rollback notes where relevant,
- the assumptions or blockers that prevent stronger conclusions.