R script to read query/table

It is simple :)

The dataset dataframe is made available to the R Transform by Power Query.

I'll see if I can break down further by walking through - here's my query after I connect to a table in my database (supplying SQL in the connection dialog will produce something similar if it runs successfully):

SQL Results

I create a folder called test in the root directory of my hard disk, e.g.:

Empty 'test' folder

In Power Query, I select Transform from the ribbon and then Run R script, e.g.:

Invoking the 'Run R script' transform

I'm now prompted to provide my code. The pre-filled comment in the text box tells me that dataset holds the input data (results of the previous step, i.e. my table), e.g.:

Empty dialog weith pre-filled comment

I want to save the output from my SQL query as results.csv in the test subfolder I created earlier, so I add the code to do this. Because Power Query tells me I can use dataset for this, I can add this to my R code, e.g.:

Utilising the 'dataset' dataframe that Power Query has informed me about

When I click OK, my code will run. Here's what my query looks like now:

I can then navigate to my folder to check I have a file:

results.csv present in my folder

I can verify this is correct by opening it, e.g.:exported .csv in VS Code

Now I know this works, I can refresh my data in Power BI Desktop any time I like and the file will be overwritten in the target location, e.g.:File after refreshing my data, with updated timestamp

I'm hoping that this clarifies things end-to-end.

Regards,

Daniel