In mysql database query, the JOIN query involves multiple tables. How to merge the existing structure to meet the result of the join query

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1

There is a requirement: in mysql database query, single table query uses a structure, JOIN table query (JOIN) involves multiple tables, need to combine multiple single table structures together, because the single table structure has been written, so at this time only want to combine multiple structures to meet, golang, my approach is:

type A struct {...}
type B struct {...}
type C struct {
  A
  B
}

Pass the C structure to the associative table query on the line, but in rust, how to achieve, look at the following code: How can the CompanyAccount struct be written to fit your needs, not foolishly rewriting the Company and Account struct fields in CompanyAccount

use mysql::{
    prelude::{FromRow, Queryable},
    PooledConn,
};

#[derive(Debug, FromRow)]
struct Company {
    id: i64,
    name: String,
    status: i16,
    err_info: Option<String>,
    account_id: i64,
    create_at: i64,
    update_at: i64,
}

#[derive(Debug, FromRow)]
struct Account {
    id: i64,
    username: i64,
    password: String,
    salt: String,
    phone: String,
    email: String,
    client: i16,
    status: i16,
    system_id: i64,
    create_at: i64,
    last_login_at: i64,
    err_info: Option<String>,
}

#[derive(Debug, FromRow)]
struct CompanyAccount {...}

fn get_info<T: FromRow + Debug>(
    conn: &mut PooledConn,
    sql: String,
) -> Result<Option<T>, Box<dyn std::error::Error + Send + Sync + 'static>> {
    let s = conn.query_first(sql)?;
    Ok(s)
}

fn main() {
    let mut cli = get_client();
    let s: Company = get_info(&mut cli, "select * from company").unwrap().unwrap();
    println!("----------{:#?}", s);

    let s1: CompanyAccount = get_info(&mut cli, "select company.*, account.*  from company left join account on company.account_id = account.id").unwrap().unwrap();
    println!("----------{:#?}", s1);
}
2

Do you have any advice from a bigwig

3

You would need to write a procedural macro in order to generate the code for CompanyAccount, but to be honest it's easier to write them by hand (unless you have tens of structs).

4

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