Instruction: Describe a detailed workflow where data from multiple sources needs to be imported, cleaned, and transformed using Power Query. Include the types of data transformations you would apply.
Context: This question evaluates the candidate's proficiency with Excel’s Power Query tool, focusing on their ability to automate repetitive data preparation tasks. It reflects on their understanding of integrating and optimizing data from diverse sources, which is crucial for effective data analysis and decision-making in tech roles.
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Let's consider a scenario relevant to a Data Analyst role, where our objective is to analyze the performance metrics of social media marketing campaigns across multiple platforms such as Facebook, Twitter, and Instagram. Each platform provides campaign performance data in different formats and structures. Our goal is to import this data into Excel, clean it, and transform it into a unified format for analysis. This scenario perfectly illustrates the necessity for Power Query in streamlining the process and ensuring data integrity.
Firstly, I would start by importing the data from each social media platform. Power Query allows us to connect to various data sources, including web pages, text files, and cloud-based storage. Assuming each platform exports their data as CSV files, I would use the 'From Text/CSV' option in Power Query to import these files into Excel. It's crucial to establish a consistent folder structure where these files...