Function diesel::pg::upsert::do_update

pub fn do_update() -> IncompleteDoUpdate

Used to create a query in the form ON CONFLICT (...) DO UPDATE ...

Call .set on the result of this function with the changes you want to apply. The argument to set can be anything that implements AsChangeset (e.g. anything you could pass to set on a normal update statement).

Note: When inserting more than one row at a time, this query can still fail if the rows being inserted conflict with each other.

Examples

Set specific value on conflict

use self::diesel::pg::upsert::*;

let user = User { id: 1, name: "Pascal" };
let user2 = User { id: 1, name: "Sean" };

assert_eq!(Ok(1), diesel::insert(&user).into(users).execute(&conn));

let insert_count = diesel::insert(
    &user2.on_conflict(id, do_update().set(name.eq("I DONT KNOW ANYMORE")))
).into(users).execute(&conn);
assert_eq!(Ok(1), insert_count);

let users_in_db = users.load(&conn);
assert_eq!(Ok(vec![(1, "I DONT KNOW ANYMORE".to_string())]), users_in_db);

Set AsChangeset struct on conflict

use self::diesel::pg::upsert::*;

let user = User { id: 1, name: "Pascal" };
let user2 = User { id: 1, name: "Sean" };

assert_eq!(Ok(1), diesel::insert(&user).into(users).execute(&conn));

let insert_count = diesel::insert(
    &user2.on_conflict(id, do_update().set(&user2))
).into(users).execute(&conn);
assert_eq!(Ok(1), insert_count);

let users_in_db = users.load(&conn);
assert_eq!(Ok(vec![(1, "Sean".to_string())]), users_in_db);

Use excluded to get the rejected value

use self::diesel::pg::upsert::*;

let user = User { id: 1, name: "Pascal" };
let user2 = User { id: 1, name: "Sean" };
let user3 = User { id: 2, name: "Tess" };

assert_eq!(Ok(1), diesel::insert(&user).into(users).execute(&conn));

let insert_count = diesel::insert(&vec![user2, user3]
    .on_conflict(id, do_update().set(name.eq(excluded(name))))
).into(users).execute(&conn);
assert_eq!(Ok(2), insert_count);

let users_in_db = users.load(&conn);
assert_eq!(Ok(vec![(1, "Sean".to_string()), (2, "Tess".to_string())]), users_in_db);