Scheduled refresh is running queries twice

[Anonymous]

Hi all,

we have scheduled refresh that is pretty big and has a lot of temp tables, it's running daily and every query it contais is ran twice - both start within few seconds.

The queries take double the time to load - spending our database resources and we had to postpone all other processes since it takes around 90 minutes to load - instead of 45 min.

Database is Amazon Redshift and we're using ODBC connector, source is written in custom SQL.

I saw some older posts, I'm wondering if anyone has found a workaround for this issue?

Thank you!

[v-chenwuz-msft · Accepted solution]

Hi @Anonymous 

I was searching and found some results about your refreshing twice, you can refer to them.

why Power BI query twice 

Power BI wants to know the schema of the table before the query actually runs, so it asks Power Query to return the top 0 rows. Unfortunately, in this case query folding can’t take place and the top 0 filter can’t be pushed back to the database, so the entire query gets run once to get the schema and once to get the data.

Maybe you can try the solution this blog has mentionedis using the Table.View M function to hard-code the schema returned by the query and implement query folding manually.

Best Regards

Community Support Team _ chenwu zhu

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

[Anonymous]

Hi Stefano,
I'm not using dataflows yet - I've have dataset and report 1:1 connection, dataset is connected to database through gateway.

Lineage:

We have full refresh every day, scheduled from Dataset settings -> Scheduled Refresh.

Thanks!

[StefanoGrimaldi]

by any chance you using dataflows connect to a data model dataset? can you share some more details on how the linages its set up and your refreshing configurations set up too.