Introduction
M is the query language for Power BI and Excel transforming data.
Read more →Welcome to M Query Guide - Your Path to SQL Proficiency!
Unlock the world of SQL with free tutorials and resources at M Query Guide. Perfect for beginners and intermediates looking to enhance their coding skills.
Basics
Setup
M setup uses Power Query Editor in Power BI or Excel.
Read more →Syntax
M syntax uses let expressions and => for data transformations.
Read more →Variables
M variables use let to define reusable data steps.
Read more →Data Types
M data types include text number and date with type inference.
Read more →Type Conversion
M type conversion uses functions like Number.FromText.
Read more →Operators
M operators include arithmetic and comparison for query logic.
Read more →If Else
M if-else statements control data flow with then and else.
Read more →Comments
M comments use // or /* */ for query annotations.
Read more →Errors
M errors use try-otherwise for robust data transformations.
Read more →Debugging
M debugging uses Query Editor steps and error messages.
Read more →Best Practices
M best practices include modular steps, clear naming.
Read more →Security Basics
M security ensures safe data handling in Power Query.
Read more →Expressions
Let Expressions
M let expressions structure queries with reusable steps.
Read more →Each Expressions
M each expressions iterate rows for transformations.
Read more →In Clause
M in clause finalizes let expressions with output.
Read more →Functions
Functions
M functions use (param) => for reusable logic.
Read more →Anonymous Functions
M anonymous functions use (x) => for inline transformations.
Read more →Recursive Functions
M recursive functions use @ for self-referential logic.
Read more →Optional Parameters
M optional parameters use optional keyword for flexibility.
Read more →Function Invocation
M function invocation uses () with parameter passing.
Read more →Text Functions
M text functions like Text.Combine manipulate strings.
Read more →Number Functions
M number functions like Number.Round process numeric data.
Read more →Date Functions
M date functions like Date.AddDays handle temporal data.
Read more →Time Functions
M time functions like Time.Hour extract time components.
Read more →Duration Functions
M duration functions like Duration.Days compute intervals.
Read more →Record Functions
M record functions like Record.Field access field values.
Read more →List Functions
M list functions like List.Sum aggregate collections.
Read more →Table Functions
M table functions like Table.AddColumn modify tables.
Read more →Data Structures
Lists
M lists use { } for ordered collections in queries.
Read more →Records
M records use [ ] for key-value pairs in data.
Read more →Tables
M tables represent tabular data with rows and columns.
Read more →Data Sources
Source Data
M source data loads from Excel CSV or databases.
Read more →Excel Source
M Excel source uses Excel.Workbook for table imports.
Read more →CSV Source
M CSV source uses Csv.Document for delimited files.
Read more →Database Source
M database source uses Sql.Database for SQL queries.
Read more →Web Source
M web source uses Web.Contents for API or HTML data.
Read more →JSON Source
M JSON source uses Json.Document for structured data.
Read more →XML Source
M XML source uses Xml.Tables for hierarchical data.
Read more →Folder Source
M folder source uses Folder.Files for batch imports.
Read more →Transformations
Filtering Rows
M filtering rows uses Table.SelectRows with conditions.
Read more →Removing Columns
M removing columns uses Table.RemoveColumns for cleanup.
Read more →Adding Columns
M adding columns uses Table.AddColumn for calculations.
Read more →Sorting Rows
M sorting rows uses Table.Sort with column orders.
Read more →Grouping Rows
M grouping rows uses Table.Group for aggregations.
Read more →Pivoting Columns
M pivoting columns uses Table.Pivot for reshaping data.
Read more →Unpivoting Columns
M unpivoting columns uses Table.Unpivot for normalization.
Read more →Merging Tables
M merging tables uses Table.Join for combining datasets.
Read more →Splitting Columns
M splitting columns uses Table.SplitColumn for text parsing.
Read more →Replacing Values
M replacing values uses Table.ReplaceValue for data cleaning.
Read more →Transposing Tables
M transposing tables uses Table.Transpose for row-column swap.
Read more →Combining Tables
M combining tables uses Table.Combine for appending data.
Read more →Custom Columns
M custom columns use Table.AddColumn with expressions.
Read more →Conditional Columns
M conditional columns use Table.AddColumn with if logic.
Read more →Joins
Table Joins
M table joins use Table.Join with inner or left outer types.
Read more →Inner Join
M inner join combines matching rows with Table.Join.
Read more →Left Outer Join
M left outer join keeps all left table rows.
Read more →Right Outer Join
M right outer join keeps all right table rows.
Read more →Full Outer Join
M full outer join combines all rows from both tables.
Read more →Parameters
Parameters
M parameters use let expressions for dynamic inputs.
Read more →Dynamic Sources
M dynamic sources use parameters for flexible imports.
Read more →Performance
Query Folding
M query folding optimizes transformations for database performance.
Read more →Step Optimization
M step optimization minimizes transformations for speed.
Read more →Buffering
M buffering with Table.Buffer improves query performance.
Read more →Error Handling
Error Handling
M error handling uses try-otherwise with custom messages.
Read more →Custom Errors
M custom errors use error function for specific failures.
Read more →Query Management
Query Dependencies
M query dependencies ensure correct step execution order.
Read more →Query References
M query references reuse existing queries for modularity.
Read more →Query Steps
M query steps organize transformations in Power Query Editor.
Read more →Patterns
Data Cleaning
M data cleaning removes nulls and duplicates with Table functions.
Read more →Data Aggregation
M data aggregation uses Table.Group for sums and counts.
Read more →Data Shaping
M data shaping pivots and unpivots for reporting formats.
Read more →Dynamic Filtering
M dynamic filtering uses parameters for flexible row selection.
Read more →Bulk Import
M bulk import uses Folder.Files for batch processing.
Read more →Data Validation
M data validation checks types and ranges with conditions.
Read more →Examples
Excel Import
M Excel import query loads tables with Excel.Workbook.
Read more →CSV Import
M CSV import query parses files with Csv.Document.
Read more →Web API Query
M web API query fetches JSON with Web.Contents.
Read more →Database Query
M database query uses Sql.Database for SQL Server data.
Read more →Data Cleaning Query
M data cleaning query removes nulls and formats text.
Read more →Aggregation Query
M aggregation query groups sales by region with sums.
Read more →Pivot Query
M pivot query reshapes sales data by month with Table.Pivot.
Read more →Join Query
M join query merges customer and order tables with Table.Join.
Read more →Dynamic Filter Query
M dynamic filter query uses parameters for date ranges.
Read more →Custom Column Query
M custom column query calculates profit with expressions.
Read more →Explore Our Tools
M Query Code Commenter
This page provides the M Query Code Commenter tool. Utilize it for your tasks.
Go to tool →M Query Data Type Analyzer
This page provides the M Query Data Type Analyzer tool. Utilize it for your tasks.
Go to tool →M Query Error Explainer
This page provides the M Query Error Explainer tool. Utilize it for your tasks.
Go to tool →M Query Formatter
This page provides the M Query Formatter tool. Utilize it for your tasks.
Go to tool →M Query Function Reference
This page provides the M Query Function Reference tool. Utilize it for your tasks.
Go to tool →M Query Step Explainer
This page provides the M Query Step Explainer tool. Utilize it for your tasks.
Go to tool →M Query to DAX Converter Preview
This page provides the M Query to DAX Converter Preview tool. Utilize it for your tasks.
Go to tool →M Query Transformation Generator
This page provides the M Query Transformation Generator tool. Utilize it for your tasks.
Go to tool →