Struct diesel::pg::upsert::IncompleteOnConflict

source · [−]
pub struct IncompleteOnConflict<Stmt, Target> { /* private fields */ }
Expand description

A partially constructed ON CONFLICT clause.

Implementations

Creates a query with ON CONFLICT (target) DO NOTHING

If you want to do nothing when any constraint conflicts, use on_conflict_do_nothing instead. See on_conflict for usage examples.

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

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

let insert_count = diesel::insert_into(users)
    .values(&user2)
    .on_conflict(id)
    .do_update()
    .set(name.eq("I DONT KNOW ANYMORE"))
    .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
let user = User { id: 1, name: "Pascal" };
let user2 = User { id: 1, name: "Sean" };

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

let insert_count = diesel::insert_into(users)
    .values(&user2)
    .on_conflict(id)
    .do_update()
    .set(&user2)
    .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 diesel::pg::upsert::excluded;

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_into(users).values(&user).execute(&conn));

let insert_count = diesel::insert_into(users)
    .values(&vec![user2, user3])
    .on_conflict(id)
    .do_update()
    .set(name.eq(excluded(name)))
    .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);

Trait Implementations

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Convert self to an expression for Diesel’s query builder. Read more

Convert &self to an expression for Diesel’s query builder. Read more

The resulting type after obtaining ownership.

Creates owned data from borrowed data, usually by cloning. Read more

🔬 This is a nightly-only experimental API. (toowned_clone_into)

Uses borrowed data to replace owned data, usually by cloning. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.