M Code in Power BI

M code, also known as Power Query M Language, is a functional programming language used in Power Query, a data connectivity and preparation tool available in Microsoft Excel, Power BI, and other Microsoft products. M code is used for data transformation tasks, such as cleaning, shaping, and combining data from various sources before loading it into the target data model.

Here's why M code is used and its key features:

1. Data Transformation: M code is used to perform a wide range of data transformation tasks, including filtering rows, removing duplicates, splitting columns, merging tables, and creating custom calculations. It allows users to manipulate data in a flexible and customizable manner.

2. Data Source Connectivity: M code provides connectivity to a variety of data sources, including databases, files, web services, and APIs. Users can use M code to retrieve data from these sources, apply transformations, and load it into their data model.

3. Repeatability and Automation: M code enables users to create reusable data transformation processes that can be applied to multiple datasets. By writing M code scripts, users can automate data preparation tasks, ensuring consistency and repeatability in their data workflows.

4. Customization and Extensibility: M code offers extensive customization and extensibility options. Users can write custom functions, create reusable modules, and define complex data transformation logic tailored to their specific requirements.

5. Integration with Power Query: M code is integrated with the Power Query user interface, allowing users to interactively build and edit data transformation steps using a visual interface. Users can switch between the graphical interface and M code view to see the underlying M code generated by their actions.

6. Error Handling and Debugging: M code provides robust error handling and debugging capabilities. Users can catch and handle errors, log diagnostic information, and troubleshoot data transformation issues using built-in functions and features.

Overall, M code is a powerful tool for data preparation and transformation, offering flexibility, repeatability, and extensibility in data workflows. It enables users to connect to various data sources, apply complex transformations, and automate data preparation tasks efficiently