SQLX Mysql Enum decode error

[amitavaghosh1]

 ColumnDecode { index: "\"template_type\"", source: "mismatched types; Rust type `template::app::model::TemplateType` (as SQL type `ENUM`) is not compatible with SQL type `ENUM`" }

#[derive(Serialize, Deserialize, Clone, Debug, EnumString, ToString, Type)]
// #[sqlx(rename="template_type", rename_all = "snake_case")] 
pub enum TemplateType {
    Email,
    Pns
}


#[derive(Serialize, Deserialize, Clone, Debug)]
pub struct Template {
    pub tname: String,
    pub template_type: TemplateType,
    pub created_at: DateTime::<Utc>
}

[amitavaghosh1]

One way to solve this is to overwrite the FromRow trait as such.

impl <'r>FromRow<'r, MySqlRow> for Template {
    fn from_row(row: &'r MySqlRow) -> Result<Self, MysqlError> {
        let tt: String = row.try_get("template_type")?;

        let template_type = match TemplateType::from_str(&tt) {
                Ok(t) => t,
                Err(_) => TemplateType::Email,
        };

        return Ok(Template{
            tname: row.try_get("tname")?,
            template_type: template_type,
            created_at: row.try_get("created_at")?
        });
    }
}

The to_string and from_str are methods from strum package, which converts enums to string and vice versa.

[bin]

I am experiencing the same issue; I've added #[repr(u8)] to my enums and represent them as TINYINTs instead in MariaDB as a temporary fix.

[ultimaweapon]

Just stumble upon this issue with 0.8.2. It seems like this should be fixed by #3371, which included in the 0.8.2 but somehow it does not work for me.

[ultimaweapon]

After digging into this found out https://github.com/launchbadge/sqlx/blob/main/sqlx-mysql/src/type_info.rs#L109 is a problem. It works if the column is nullable and have a default value otherwise it will fails.