While developing I run PostgreSQL in a way that logs everything I sent to it via DBI. This has the advantage of letting me see the complete SQL sent to the server.

However, taking a wild guess I would think that your SQL, which without adding actual values looks a bit like this:

insert into foo (source, name,date, status) values (?,?)
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has the wrong number of question marks. You are inserting source, name, date, status but you only have two question marks. Just a thought.