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Data cleaning and transformation

Data cleaning and transformation are crucial steps in the data preparation process for creating accurate and insightful Power BI reports. Power BI provides a robust set of tools for these tasks through Power Query Editor. Here’s an in-depth guide to data cleaning and transformation using a sample dataset.


Filtering

Data filtering in Power BI is a powerful feature that allows users to focus on specific subsets of data within their reports and dashboards. Filters can be applied at various levels, including visual, page, and report levels. Here's a detailed overview of data filtering in Power BI along with an example to illustrate how it works.


Sorting

Sorting in Power BI allows you to organize your data in a meaningful order within visuals and reports. Sorting can be applied to different types of visuals like tables, matrices, and charts to enhance the clarity and analysis of data.


Merging

Merging datasets in Power BI allows you to combine two or more tables into a single table based on a common field. This is useful for enriching your data with additional information or for performing complex data analysis. The merging process in Power BI is similar to SQL joins (like INNER JOIN, LEFT JOIN, etc.).


Appending

Appending datasets in Power BI allows you to combine rows from two or more tables into a single table. This is useful when you have similar data stored in multiple tables and want to consolidate them into one. Appending can be thought of as a union operation in SQL.


Pivoting

Pivoting in Power BI, often referred to as "unpivoting" in the context of reshaping data, allows you to transform your data table so that rows become columns or vice versa. This is particularly useful when dealing with datasets that have columns representing different values over time or categories that you want to analyze more effectively.



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