This does help to clear things up. But at the same time it leaves a lot of questions.

I am not trying to insert anything into the database. Where would I put the placeholder in a plain old select statement? || Can you direct me to a node with the answer?

Does foreach my $var (@list); cause $var to be in list context? || Can you direct me to a node with a good explanation of the differences in context?

Does @l_sqlparams = ($var); put $var back into an array from list context? || Can you direct me to a node with an explanation?