Solved Greyed out checkbox on report

[mafhobb]

I have a report with a query as source. This query contains a checkbox field from a table (on the table it is set up as Yes/No, default=No). In the query results, the checkboxes show up correctly (either marked or unmarked). On the report I also have a checkbox to show the results of this query, however the checkbox is greyed out. Why?
I do not have any intention to enter data through the report, I just want to show on the report the value that the field has in the table with this checkbox. My expectations were to have a marked or unmarked checkbox, the same as on the query results.
Why is it displaying greyed out?

 

[mafhobb]

I have figured out why/when this happens, but I still need a solution.
The checkboxes on the report show up in the report when there are no query results at all. When there are results, then the checkboxes appear correctly.
So, how do I hide the boex when there are no query reults?

 

[ebs17]

Greyed out checkbox

That's probably because it's the third state of a boolean field.

Modern SQL: Three-Valued Logic (3VL) — Purpose, Benefits and Special Cases

Making decision despite missing SQL data (NULL): How to avoid OR…IS NULL in the WHERE clause.

modern-sql.com

In the query, try something like the following:

Nz(BooleanField, False)

This replaces the unknown content (NULL) with false.

 

[mafhobb]

Many thanks!