Questions from Rust newbies

[Vjze]

When there are more than 12 query items, an error will be reported, but within 12 items, it can run normally. Why is this?

20231206_222621.mp4

[blackbeam]

Hi.
12 is a usual maximum arity for tuples that implements traits. Consider using something like this:

conn.query_map("...", |row: mysql_async::Row| {
    // do something with mysql_async::Row
});