power-bi-agent-skills: Skill for Claude Code

Power Query Skill

This skill helps write Power Query (M language) for data transformation in Power BI semantic models.

When to Use This Skill

• Connecting to data sources (SQL, Excel, APIs, etc.)
• Transforming data (filtering, merging, pivoting)
• Creating parameters for dynamic queries
• Optimizing query performance (query folding)
• Setting up incremental refresh
• Error handling in data loads

M Language Fundamentals

Basic Structure

Every M query follows this pattern:

let
    // Step 1: Connect to source
    Source = ...,

    // Step 2: Transform
    Transformed = ...,

    // Step 3: More transformations
    Final = ...
in
    Final

Key Concepts

Concept	Description
let...in	Defines a query with steps
Step names	Descriptive, PascalCase
#"Name"	Names with spaces/special chars
each	Shorthand for (_) => _
_	Current row/value in each

Data Types

// Primitive types
type text
type number
type date
type datetime
type datetimezone
type time
type duration
type logical
type null
type binary

// Complex types
type list
type record
type table
type function

// Nullable types
type nullable text

Type Conversion

// Convert to types
Text.From(123)                    // "123"
Number.From("123")                // 123
Date.From("2024-01-15")           // #date(2024, 1, 15)
DateTime.From("2024-01-15 10:30") // #datetime(2024, 1, 15, 10, 30, 0)
Logical.From(1)                   // true

// Parse with format
Date.FromText("15/01/2024", [Format="dd/MM/yyyy"])

Data Source Connections

SQL Server

let
    Source = Sql.Database("server.database.windows.net", "DatabaseName"),
    Schema = Source{[Schema="dbo", Item="TableName"]}[Data]
in
    Schema

SQL Server with Query

let
    Source = Sql.Database("server.database.windows.net", "DatabaseName", [
        Query = "SELECT * FROM dbo.Sales WHERE Year >= 2023"
    ])
in
    Source