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Having been reminded of this request just now by @dbaum tagging me and linking to this in his other thread here, I must say that I no longer believe this is an appropriate request. At the time the request was made, I was very familiar with programming languages, but not very familiar with database concepts. Having learned more about databases since then, I've come to understand one point in particular:
A NULL value is its own special case, and is not equivalent to anything else, even itself.
To explain that further, a NULL value means that the value is unknown. This is much different than the confirmed absence of a value. A text value can be NULL, or it can be a blank string "", and these 2 things are very different and not equivalent. Similarly, a Boolean value can be NULL, or it can be FALSE, and these 2 things are also not equivalent.
As Appsheet generally follows database concepts, instead of programming language concepts, I no longer feel that NOT( [column] ) should equal TRUE, when [column] is a Yes/No type without a value.
For more reading on the subject, I recommend a Google search as such:
FWIW, I've found it handy to manage some boolean columns as having 3 possible values from the AppSheet perspective: true, false, or blank. The main use case is to distinguish between:
rows for which the column hasn't yet been populated (i.e., I leave the initial value property empty) because the row hasn't reached the pertinent stage in the typical lifecycle for that table's rows
rows for which something has occurred that led to populating the column as either true of false
As long as I'm aware of scenarios where I need to distinguish between NOT([Boolean Column]) and the more explicit [Boolean Column] = false, I think the approach is working out.
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