Diesel:添加子查询的结果

use diesel::prelude::*;
use diesel::dsl::sql;

// 定义数据库表的结构体
table! {
    users {
        id -> Integer,
        name -> Text,
        age -> Integer,
    }
}

fn main() {
    use self::users::dsl::*;

    let connection = establish_connection();

    // 添加子查询的结果
    let subquery = users.select(name).filter(age.gt(18));

    // 主查询
    let results = users.filter(sql("name IN (").bind::<Text, _>(subquery).sql(")"))
        .load::<(i32, String, i32)>(&connection)
        .expect("Error loading users");

    for (id, name, age) in results {
        println!("ID: {}, Name: {}, Age: {}", id, name, age);
    }
}

fn establish_connection() -> PgConnection {
    // 连接数据库的代码
}