Does Power BI have some sort of Query Process Manager?

[MarCat]

Have 6 datasets retrieved from the web.  Each dataset needs various clean-up actions and various changes are made to headers etc.  When the 6 datasets are 'clean' they're appended with eachother as one new dataset.  The new dataset has the majority of changes, including many new added custom columns.  Everything works fine within the query editor.  However when I try to apply and save I get bombarded with errors.  Pretty sure this is because the queries are not processed in any particular order, and hence the append query will fail as the other 'smaller' queries haven't finished doing their tasks as yet.  Does Power BI have some sort of Query Process Manager where one can set the mandatory order in which the queries must process, and the next query can only process if the current one being processed has fully finished without errors?  It seems a logical component when working with databases and datasets.

[BA_Pete · Accepted solution]

Hi @MarCat ,

As far as I'm aware, when PQ sets out the query plan for a refresh it will 'work backwards' like pretty much any other query handler i.e. it will scan your final query, see that it relies on previous queries for its source, and so prioritise the previous queries before attempting the final query.

You can manage/test this by adjusting the following values in File > Options & Settings:

For all PBIX files globally:

For current file only:

My gut feeling is that the issue you are experiencing has nothing to do with the actual evaluation of the queries by the handler, so you may get more value by listing the errors you are receiving here and we can look to address them specifically.

Pete