#[derive(flatten)] doesn't work with query_as! macro

[miquels]

Bug Description

#[derive(flatten)] doesn't work with the query_as! macro. It fails to compile. The example code in the provided github repo does compile when the sqlx::query_as function is used.

$ cargo run
   Compiling sqlx-flatten-fails-with-query_as-macro v0.1.0 (/usr/home/miquels/rust/sqlx-flatten-fails-with-query_as-macro)
error[E0560]: struct `AccountKeyword` has no field named `name`
  --> src/main.rs:46:19
   |
46 |       let account = sqlx::query_as!(
   |  ___________________^
47 | |         AccountKeyword,
48 | |         "SELECT 1 as id, 'foo' as name, 'bar' as surname"
49 | |     )
   | |_____^ `AccountKeyword` does not have this field
   |
   = note: available fields are: `id`, `info`, `default`
   = note: this error originates in the macro `$crate::sqlx_macros::expand_query` which comes from the expansion of the macro `sqlx::query_as` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0560]: struct `AccountKeyword` has no field named `surname`
  --> src/main.rs:46:19
   |
46 |       let account = sqlx::query_as!(
   |  ___________________^
47 | |         AccountKeyword,
48 | |         "SELECT 1 as id, 'foo' as name, 'bar' as surname"
49 | |     )
   | |_____^ `AccountKeyword` does not have this field
   |
   = note: available fields are: `id`, `info`, `default`
   = note: this error originates in the macro `$crate::sqlx_macros::expand_query` which comes from the expansion of the macro `sqlx::query_as` (in Nightly builds, run with -Z macro-backtrace for more info)

For more information about this error, try `rustc --explain E0560`.
error: could not compile `sqlx-flatten-fails-with-query_as-macro` due to 2 previous errors

Minimal Reproduction

repo: https://github.com/miquels/sqlx-flatten-fails-with-query_as-macro
code is in src/main.rs
reproduce: just do cargo run

Info

• SQLx version: 0.6.2
• SQLx features enabled: ["runtime-tokio-rustls", "sqlite" ] }
• Database server and version: SQLite
• Operating system: FreeBSD 13.1
• rustc --version: rustc 1.64.0 (a55dd71d5 2022-09-19)

[CosmicHorrorDev]

The query_as!() macro doesn't use FromRow. It just directly constructs the struct

I thought I remembered seeing that mentioned in the docs somewhere, but I can't find it now

[CosmicHorrorDev]

Poked around some more and found that this is detailed in the docs for query_as!() (Don't know how I missed that before)

This macro does not use FromRow; in fact, no trait implementations are required at all, though this may change in future versions.

Along with providing a lot more details as to why (in short this allows for enforcing more checks at compile time)

[miquels]

I see, thanks for replying. I love the compile-time checks sqlx does, and I hoped it was just an oversight/bug that it could not be used with flatten. Feel free to close this issue, or maybe relabel it as 'feature request' or 'improvement'?

[abonander]

Long-standing feature request: #514

Closing as duplicate.

[caioluis]

How did you avoid this problem? I'm facing the same issue