pub fn with_arg(mut self, name: &'static str, value: &'a ThreadSafeDebug) -> Self {
        self.data.args.inner.push((name, value));
        self
    }
Adds a traced query argument. The argument will be logged (using `Debug`) if the query executes too slow
or finishes with an error.
core/lib/db_connection/src/instrument.rs