Power BI - CRUD analysis how? - powerbi

Question

I have 2 data sources - Source 1 ( SharePoint List ) & Source 2 ( Cloud Source ). I bring both into Power BI. They each have a key to identify a unique instance of a record.
In Power BI I have been asked to identify the New Inserts / Deletes and Updated Records.
So is there an easy way of doing this?
Table 1
Key Column 1 Column 2 Column 3
Table 2
Key Column 1 Column 2 Column 3

Answer 1

You can use Merge queries transformation in Power Query Editor to do that. Left Anti and Right Anti join kinds will give you the rows that exists only in the first or second data source. Inner will give you the rows that exists in both (based on their key value) and later you can compare the other columns to decide are they modified or not.
Lets assume there are two data sources, as follows:
Source 1
Key
Column 1
Column 2
Column 3
1
initial value
initial value
initial value
2
initial value
initial value
initial value
3
initial value
initial value
initial value
Source 2
Key
Column 1
Column 2
Column 3
1
initial value
initial value
initial value
2
modified value
initial value
initial value
4
initial value
initial value
initial value
1 exists in both sources and is not modified;
2 exists in both sources but is modified (Column 1 has different values);
3 exists only in Source 1;
4 exists only in Source 2.
In Power Query Editor, in Home tab of the ribbon, in Combine group, click on Merge Queries -> Merge Queries as New, select Source 1 as the first source, Source 2 as the second source, set the join kind to be Left Anti and make sure Key columns in both sources are selected:
This will give you the rows, that exists only in Source 1, i.e. only 3 (and remove the columns from Source 2 there, because they are not needed):
Do the same merge again, but swap the sources:
to get the rows, that exists only in Source 2, i.e. 4:
And then do it again, but this time set the join kind to be Inner:
Click on the button in the header of Source 2 column and add all the columns except Key and add a conditional column (Add Column -> General -> Conditional Column) as follows (note, that the screenshot is incorrect - the third comparison should be between Column 3 and Source 2.Column 3):
It will tell you is this row modified (2) or not (1):
If you want you can click the button in the header of the custom column and filter the result to show only the rows, where the value is Modified, which will leave only 2 in the result: