diesel-selectable-macro
When inserting, Diesel allows you to derive the Insertable trait, which
inserts keys by name:
use diesel::prelude::*;
#[derive(Insertable)]
#[diesel(table_name = users)]
struct User {
email: String,
password_hash: String,
// There's another field, `phone`, but we are not writing it.
}
// later on...
fn write(user: User) -> QueryResult<usize> {
diesel::insert_into(users::table).values(user).execute(conn)
}This crate offers a similar derive trait for reading data. Diesel's
Queryable trait reads by position rather than field name, but sometimes field
name is more convenient:
use diesel::prelude::*;
use diesel_selectable_macro::Selectable;
#[derive(Queryable, Selectable)]
#[diesel(table_name = users)]
struct User {
email: String,
password_hash: String,
// There's another field, `phone`, but we do not need to read it.
}
// later on...
fn read(email: String) -> QueryResult<User> {
User::select().filter(crate::schema::users::email.eq(&email)).get_result(conn)
}The automatically derived select method provides the explicit fields to
Diesel, corresponding to the struct fields.