Microsoft Power BI Data Analyst Practice Question

The correct process involves creating dimension tables from the main query and then using those dimensions to prepare the final fact table. First, you should create new queries that reference the original 'SalesData' query for each dimension you want to create (e.g., 'DimCustomer', 'DimProduct'). Using 'Reference' is efficient as it creates a dependency on the source query without duplicating the data in memory. In each of these new dimension queries, you isolate the relevant columns (e.g., 'CustomerName' for 'DimCustomer'), remove all other columns, and then remove duplicate rows to create a unique list of dimension members. It is a best practice to add a unique index column (surrogate key) to each dimension table. After the dimensions are created, you return to the 'SalesData' query, which will serve as your fact table. You merge this query with each new dimension table to bring in their surrogate keys. Finally, you remove the original, now-redundant descriptive columns (e.g., 'CustomerName', 'ProductCategory') from the fact table, leaving only the foreign keys and the numeric measures.