We have two options to combine the files.
- Combine and Transform
- Combine and Load
In this article, we will see how to use ‘Combine and Transform’. Have a look at the files.
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See below the structure of each file, Employee1
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Employee2
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Employee3
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Follow the below steps to combine and transform the data. Step 1 To import data, go to ‘Home’ tab click on ‘Get data’ select the ‘Folder’ source then click ‘Connect’.
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Paste the path of the folder and click ok
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After clicking on ‘Ok’ you will see what is located in this folder. You can see the meta data of the files like name, type, when it last modified etc.
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Click on highlighted text i.e. ‘Combine and Transform’. Step 2
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Choose the first file to combine and click on ‘Ok’. Now Power query editor will be opened and you can see that all three tables are combined.
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Here you can see that Power BI added one additional column that specifies from which file is the specific row in the table.
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This column is very important, and we can use it like every other column to slice data based on its values (In this case its OFC_LOC). But in this case, we already have a Country in OFC_LOC column, therefore we do not need it and we will remove it. By having the column selected, we click Remove Columns.
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Step 3 Now go to file tab and click on ‘Close & Apply’. You can perform multiple tasks in power query editor and apply changes.
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Your changes will be saved and shown on Power BI desktop window.
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Step 4 Now you can create a report from this table. Here I am using Pie chart and two columns i.e. ‘Ofc_loc’ and ‘Salary’.
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Second report is showing the total Salary of all countries. To do so I am using card visualization with Sum of salary.
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Summary
Try these above steps, you will be able to create a combine table by using power query. You can transform the data as per your need in power query editor. I will write a separate article on Power Query Editor so continue with me. Thanks for reading.
Ref: https://www.c-sharpcorner.com/article/combine-and-transform-data-of-multiple-files-located-in-a-folder-in-power-bi/