MySQL: time and chrono type tests are broken by MySQL server 8.0.28

[abonander]

I've figured out why CI is failing for MySQL.

For some reason, in the newest version of MySQL (8.0.28), for SELECT ? when a TIME, DATE, DATETIME or TIMESTAMP type is bound,
the Binary Resultset packet reports that the column has a type of MYSQL_TYPE_VAR_STRING.

They mention some changes to date/time type handling in their changelog which I strongly believe is relevant: https://dev.mysql.com/doc/relnotes/mysql/8.0/en/news-8-0-28.html#mysqld-8-0-28-data-types

(And coincidentally acknowledge the breakage from 8.0.27 I previously had to fix here:

sqlx/sqlx-test/src/lib.rs

Lines 200 to 201 in 2182925

	// MySQL 8.0.27 changed `<=>` to return an unsigned integer
	"SELECT CAST({0} <=> ? AS SIGNED INTEGER), {0}, ?"

)

Question is, do we just fix this in the type tests or report this as a database bug, or both?

[abonander]

Submitted MySQL bug: https://bugs.mysql.com/bug.php?id=106352

[abonander]

Update: fix coming in 8.0.29! (See conversation in link above)

[abonander]

I've fixed CI for now by pinning the version at 8.0.27:

sqlx/tests/docker-compose.yml

Lines 10 to 11 in 7fd324d

	# FIXME: 8.0.28 introduced a regression in our type tests: https://github.com/launchbadge/sqlx/issues/1664
	# The MySQL devs agreed that it was a regression and that it will be fixed in 8.0.29

[hollow-owl]

This also happens on mariadb Ver 15.1 Distriib 10.7.3-MariaDB

[grooverdan]

@hollow-owl did the MariaDB get resolved? Its not merged from MySQL and I couldn't find a MariaDB bug. We'll see with #2739 I guess.

[grooverdan]

On MariaDB we ported MySQL's test case and we aren't affected (MariaDB/server#2752).

Also when a TIMESTAMP is bound a TIMESTAMP is returned.