Managing a Master Dataset and Date Column Management

[irnm8dn]

I have a master dataset of approximately 2.5MM rows.   

There are a number of columns that contain various date columnsrepresenting Start/End dates.  Not all these date columns apply to every row.

When there is a date field that is blank or N/A, upon import PowerBI defaults a date  of 12/30/1899.  I believe this is the way that PBI tries to handle a null value (or possibly a non-date data).

That being the case, I am looking for suggestion about how to have PBI  categorize the column as a date, but manage the null values where they do not apply.  When they do not apply, and are otherwise "blank" or N/A - the ideal solution would be that they are not populated.

All suggestions are welcome.

[mow700]

You may be able to use the "Replace Values" command in the "Transform" section of the "Home" ribbon of your query in edit mode to handle more complicated categorization.  Remember to select the column you want to handle to enable the command.

[irnm8dn]

Replace values won't work, as it is looking to preserve the date format and requires the replacement to be a legitimate date.

[mow700]

What is the specified data type for this column in the query?  I just created a simple manual table with a data sample, and I'm not seeing the default behavior you mentioned.  When my source data is NULL, weather I specify Date or Text data type, NULLS persist and are not replaced with 12/30/1899 as you described:

When I verify the results in my model, I see the same:

Where are you seeing the default 12/30/1899 values?