aliasing the NULL of a BIT column returns TRUE in the export

[EibertVantHof]

Thanks for making and sharing this extension, we have used it for a while.
Now we did stumble apon a bug.

Context
I am using ExportAll in multiple dashboards.
This error already exists in Tableau Desktop and also transfers to Tableau Server.

We have a bit column whether a real estate object includes a parking space.
This can thus be

• True
• False
• NULL

We have given the NULL value an alias, to make it easier understandible to our end users.

Observations
When exporting this table:

• TRUE and FALSE are shown correctly
• NULL (with alias) is shown as TRUE in the export

When I clear the alias

• TRUE and FALSE are shown correctly
• NULL is correctly shown as NULL

Hence, the issue only arises when you have an alias, which is handled as TRUE.