MSSQL: TinyInt Decodes/Encodes to wrong datatype

[zibebe]

Bug Description

According to Microsofts definition a TinyInt is a value between 0..255 so it must be a u8. Current implementation uses i8 for this.
https://docs.microsoft.com/de-de/sql/t-sql/data-types/int-bigint-smallint-and-tinyint-transact-sql?view=sql-server-ver15

Minimal Reproduction

Does not Work because 133 does not fit into an i8

#[derive(sqlx::Type)]
#[repr(i8)]
pub enum Quality {
    Good = 0,
    Bad = 1,
    Doubtful = 16,
    InitialValue = 133,
}

Must be:

#[derive(sqlx::Type)]
#[repr(u8)]
pub enum Quality {
    Good = 0,
    Bad = 1,
    Doubtful = 16,
    InitialValue = 133,
}

But Produces:

the trait bound `u8: sqlx::Decode<'_, _>` is not satisfied
the following other types implement trait `sqlx::Decode<'r, DB>`:
  f32
  f64
  i16
  i32
  i64
  i8

Info

• SQLx version: v0.6.1
• SQLx features enabled: "mssql", "runtime-tokio-rusttls"
• Database server and version: Microsoft SQL Server 15.0.2000
• Operating system: macOS 12.5.1
• rustc --version: rustc 1.63.0 (4b91a6ea7 2022-08-08)

[abonander]

Yeah, simple mixup. MySQL's TINYINT type is signed and all the rest of MSSQL's integer types are signed, so it's an easy mistake to make.

[abonander]

Closed by #2074