# Queries
When using Atmosphere, you have two options for writing queries. Once you
annotate your entities with `table`, it gives you the ability to use querying
traits that Atmosphere comes with. However, you can at any point reach down
and write your queries in raw SQL, the way you would if you used `sqlx`
directly.
## Using Atmosphere Traits
Given the Schema from the section before, here is some examples that show how
Atmosphere creates traits that allow for simple operations on the tables.
```rust
# extern crate atmosphere;
# extern crate sqlx;
# extern crate tokio;
# use atmosphere::prelude::*;
# #[derive(Debug, PartialEq)]
# #[table(schema = "public", name = "user")]
# struct User {
# #[sql(pk)]
# id: i32,
# name: String,
# #[sql(unique)]
# email: String,
# }
# #[derive(Debug, PartialEq)]
# #[table(schema = "public", name = "post")]
# struct Post {
# #[sql(pk)]
# id: i32,
# #[sql(fk -> User, rename = "author_id")]
# author: i32,
# #[sql(unique)]
# title: String,
# }
# async fn test() -> std::result::Result<(), Box<dyn std::error::Error>> {
let database = std::env::var("DATABASE_URL").unwrap();
let pool = atmosphere::Pool::connect(&database).await?;
let mut user = User {
id: 0,
name: "demo".to_owned(),
email: "some@email.com".to_owned(),
};
user.save(&pool).await?;
user.delete(&pool).await?;
user.create(&pool).await?;
assert_eq!(
User::read(&pool, &0).await?,
User::find_by_email(&pool, &"some@email.com".to_string()).await?.unwrap()
);
let mut post = Post {
id: 0,
author: 0,
title: "test".to_owned()
};
post.save(&pool).await?;
Post::find_by_author(&pool, &0).await?;
// Inter-Table Operations
Post { id: 1, author: 0, title: "test1".to_owned() }
.author(&pool).await?;
user.posts(&pool).await?;
user.delete_posts(&pool).await?;
# Ok(())
# }
# fn main() {}
```
## Using raw SQL
As previously explained, it is always possible to reach down and perform raw SQL
queries on an Atmosphere pool, since it is just an alias for an `sqlx` one.
```rust
# extern crate atmosphere;
# extern crate sqlx;
# extern crate tokio;
# use atmosphere::prelude::*;
# async fn test() -> std::result::Result<(), Box<dyn std::error::Error>> {
let database = std::env::var("DATABASE_URL").unwrap();
let pool = atmosphere::Pool::connect(&database).await?;
sqlx::query("DROP TABLE foo;")
.execute(&pool).await?;
# Ok(())
# }
# fn main() {}
```