Forum Discussion
incremental refresh with Web.Contents not working
Exactly, it's just a warning, not an error message. If you know that your data source honors the RangeStart/RangeEnd parameters (in the appropriate format conversion ) then incremental refresh will work. The only sure way to validate incremental refresh is to look at the partition statistics in the XMLA endpoint. If you see only one partition then incremental refresh likely doesn't work. If you see multiple partitions then it works. I have a blog entry on that subject if you are interested.
Hi jlammens ,
Query folding is the root of incremental refresh. It's important the partition filters are pushed to the source system when queries are submitted for refresh operations. To push filtering down means the datasource should support query folding. Most data sources that support SQL queries support query folding. However, data sources like flat files, blobs, and web feeds typically do not. In cases where the filter is not supported by the datasource back-end, it cannot be pushed down. In such cases, the mashup engine compensates and applies the filter locally, which may require retrieving the full dataset from the data source. This can cause incremental refresh to be very slow, and the process can run out of resources either in the Power BI service or in the on-premises data gateway if used.
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.
Best Regards,
Dedmon Dai
Thank you for your help. This particular web API does in fact support query folding, as evident from the RangeStart and RangeEnd parameters being passed as query parameters. This works fine and produces the expected results in PBI desktop or service without incremental refresh turned on, but it fails in the service once incremental refresh is turned on.