Incremental refresh in Power BI very briefly

By default, Power BI uses full refresh of tables. Which means that before any refresh, all data from previous load are deleted.

But you can also use the incremental refresh. To keep some of original data (or all) and change (or add) just new values. Obviously, this load can be much quicker when you don´t load everything again and again.

How to do it? You have to do three steps:pří

• Create parameters
• Setup filter
• Setup the incremental refresh itself

Parameters

Create two parameters. Their names have to be RangeStart and RangeEnd. The datatype has to be Date Time (the same asi the date column in table).

Default value of RangeStart has to be lower then oldest date in table and RangeEnd has to be higher then potential newest date.

Filter setup

Set the custom filter on the date column, defining, that data has to be between parameters. 

Incremental refresh

Close the Power Query editor. Click on three dots at table and select Incremental refresh. 

Switch on the incremental refresh and fill in the two fields.

In the first one define the length of period, that has to be kept. Everything older will be delete. In second parameter define the length of period, which has to be refreshed / added.

The incremental refresh works after upload to Powerbi.com.