Weird error with the f32 type, is real on postgre but my model doesn't work

[freinn]

Hi! I have this working struct for a model:

#[derive(Queryable)]
pub struct EntradaBlog {
    pub id_entrada_blog: i32,
    pub titulo: String,
    pub fecha_publicacion: NaiveDateTime,
    pub contenido: String,
    pub tiempo_de_lectura: i16, // SmallInt
}

It runs fine and I can query my postgresql table, but I'm having problems with the last field of this struct:

#[derive(Queryable)]
pub struct Cuadro {
    pub id_cuadro: i32,
    pub titulo: String,
    pub autor: String,
    pub descripcion: String,
    pub fecha_realizacion: Option<NaiveDateTime>,
    pub id_tecnica: i32,
    pub ancho: i16,
    pub alto: i16,
    pub precio: f32,
}

The field precio is a real on postgresql:

id_cuadro         | integer                     | not null default nextval('cuadros_id_cuadro_seq'::regclass)  | plain    |              | 
 titulo            | character varying(200)      | not null                                                     | extended |              | 
 autor             | character varying(200)      | not null                                                     | extended |              | 
 descripcion       | text                        | not null                                                     | extended |              | 
 fecha_realizacion | timestamp without time zone |                                                              | plain    |              | 
 id_tecnica        | integer                     | not null default nextval('cuadros_id_tecnica_seq'::regclass) | plain    |              | 
 ancho             | smallint                    | not null                                                     | plain    |              | 
 alto              | smallint                    | not null                                                     | plain    |              | 
 precio            | real                        | not null                                                     | plain    |              | 
Indexes:
    "cuadros_pkey" PRIMARY KEY, btree (id_cuadro)
Foreign-key constraints:
    "cuadros_id_tecnica_fkey" FOREIGN KEY (id_tecnica) REFERENCES tecnicas(id_tecnica)

And when I try to do a simple query (equivalent to select * from cuadros) I get a compiler error:

error[E0277]: the trait bound `Cuadro: diesel::Queryable<(diesel::types::Integer, diesel::types::Text, diesel::types::Text, diesel::types::Text, diesel::types::Nullable<diesel::types::Timestamp>, diesel::types::Integer, diesel::types::SmallInt, diesel::types::SmallInt, diesel::types::Float), _>` is not satisfied
   --> src/main.rs:111:10
    |
111 |         .load::<Cuadro>(&connection)
    |          ^^^^ the trait `diesel::Queryable<(diesel::types::Integer, diesel::types::Text, diesel::types::Text, diesel::types::Text, diesel::types::Nullable<diesel::types::Timestamp>, diesel::types::Integer, diesel::types::SmallInt, diesel::types::SmallInt, diesel::types::Float), _>` is not implemented for `Cuadro`

What I'm doing wrong?

[sgrif]

You're certain that column is the issue? Nothing looks out of place to me. The only thing that jumps out to me that could be the issue is a mismatch between chrono versions. Are you using Chrono 0.2.x and Diesel 0.10.x?

[sgrif]

(Also this isn't related to your bug, but, you probably shouldn't use floats for currency. precio_en_centavos as an integer would be the standard way to do it 😉)

[sgrif]

I attempted to reproduce your issue and was unable to do so. The code that I used to try to reproduce is at https://gist.github.com/sgrif/6a1a7af32274b19f43cad5c83131e811. This code compiled successfully. Can you please provide additional information that I can use to reproduce, preferably in the same form as that gist?

[freinn]

Thanks for the caring in your answer, and your consideration. I've uploaded my private git repo to github so you can test it easily, here. My code organization is poor. I have to split it into modules but I prefer to have all working before.

[sgrif]

You have multiple structs called Cuadro. The failure here is because Cuadro is referring to the struct here, which does not implement Queryable, not the one here which does.