The CURRENT FILE options must be set per the Power BI Desktop file and are particularly important when creating a new dataset:
- Disable the automatic column type and header detection for unstructured sources
- Disable all relationship options, including the import of relationships from data sources and the detection of new relationships after data is loaded
- Assuming a date dimension table is available to the dataset, disable the Auto Date/Time option
- For larger import datasets with many queries, disable the parallel loading of tables
- Click the OK button in the bottom-right corner of the Options dialog to apply these settings:
Power BI Desktop Options – CURRENT FILE Data Load
The dataset designer should explicitly apply the appropriate data types within the M queries, accessing any unstructured sources, such as Excel files. Likewise, the dataset designer should have access to data source documentation or subject matter experts regarding table relationships. Furthermore, the columns and hierarchies of the dataset's date dimension table can be used instead of the automatic internal date tables associated with the Auto Date/Time option.
Large Power BI datasets with multiple fact tables can contain many queries which, if executed in parallel, can overwhelm the resources of the source system resulting in a data refresh failure. Disabling the parallel loading of tables, therefore, improves the availability of the dataset and reduces the impact of the refresh process on the source server.
When Power BI Desktop is being used for report development rather than dataset development, the Query reduction in CURRENT FILE options can benefit the user experience. These options, including the disabling of cross-highlighting by default and the use of an Apply button for slicer and filter selections, result in fewer report queries being generated. Particularly for large and DirectQuery datasets, these options can contribute to more efficient and responsive self-service experiences with reports.