couldn't connect to MySQL 5.7 with AnyPool

[LebranceBW]

The Problem I met

When I try to use AnyPool as connection pool for MySQL connections, It paniced at first connect. the stack is:

2021-11-16T08:22:51.269164Z INFO sqlx::query: SET sql_mode=(SELECT CONCAT(@@sql_mode, ',PIPES_AS_CONCAT,NO_ENGINE_SUBSTITUTION')),time_zone='+00:00',NAMES …; rows: 0, elapsed: 6.555ms

SET
sql_mode =(
SELECT
CONCAT(
@ @sql_mode,
',PIPES_AS_CONCAT,NO_ENGINE_SUBSTITUTION'
)
),
time_zone = '+00:00',
NAMES utf8mb4 COLLATE utf8mb4_unicode_ci;

thread 'main' panicked at 'Failed to initialize application: cannot initialize pool with mysql://zetta-server-doc.pek01.rack.zhihu.com:4001/search_doc

Caused by:
0: error returned from database: 1105 (HY000): UnknownType: *ast.SelectField
1: 1105 (HY000): UnknownType: *ast.SelectField', colos-rs-server/src/main.rs:19:10
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

code related:

        let pool = AnyPoolOptions::new()
            .idle_timeout(Duration::from_millis(300))
            .connect_timeout(Duration::from_secs(1))
            .max_connections(100)
            .min_connections(3)
            .connect(&url)
            .await
            .with_context(|| format!("cannot initialize pool with {}", url))?;

version info

• mysql: 5.7.25
• sqlx: sqlx = { version = "0.5.9", features = ["runtime-tokio-rustls", "mysql", "sqlite", "any", "chrono"] }
• rust: nightly-2021-11-01
• tokio: tokio = {version = "1.12.0", features = ["full"]}

The cause I guess

After the panic, I tried to connect to another MySQL database with version 8.0.26 and it worked. So I guess the key point is Mysql version.

[xieyicai]

I encountered the same problem.