I had been getting a unique key violation on an insert that I was
unable to understand.

I solved one part by removing the unique constraint on this string
field that didn't really belong.

But now I can also understand a bit more of why the violation was
occuring:

no matter what I pass to the query's param for the insert, what
gets posted is the value that was inserted on the first execution
of this insert query.

I can read the data from the variable that is passed to the param
and it is ok.

I can read what appears to be in the param just prior to ExecSQL
and it still appears to be ok.

But what actually gets posted - for this field only - is the value
that was posted on the component's first execution of the program
cycle.

I hope that there is just something about preparing or unpreparing
or something like that which I need to understand.