Function diesel::dsl::insert_into
source · [−]pub fn insert_into<T: Table>(target: T) -> IncompleteInsertStatement<T>
Expand description
Creates an INSERT
statement for the target table.
You may add data by calling values()
or default_values()
as shown in the examples.
Backends that support the RETURNING
clause, such as PostgreSQL,
can return the inserted rows by calling .get_results
instead of .execute
.
Examples
let rows_inserted = diesel::insert_into(users)
.values(&name.eq("Sean"))
.execute(connection);
assert_eq!(Ok(1), rows_inserted);
let new_users = vec![
name.eq("Tess"),
name.eq("Jim"),
];
let rows_inserted = diesel::insert_into(users)
.values(&new_users)
.execute(connection);
assert_eq!(Ok(2), rows_inserted);
Using a tuple for values
let new_user = (id.eq(1), name.eq("Sean"));
let rows_inserted = diesel::insert_into(users)
.values(&new_user)
.execute(connection);
assert_eq!(Ok(1), rows_inserted);
let new_users = vec![
(id.eq(2), name.eq("Tess")),
(id.eq(3), name.eq("Jim")),
];
let rows_inserted = diesel::insert_into(users)
.values(&new_users)
.execute(connection);
assert_eq!(Ok(2), rows_inserted);
Using struct for values
#[derive(Insertable)]
#[diesel(table_name = users)]
struct NewUser<'a> {
name: &'a str,
}
// Insert one record at a time
let new_user = NewUser { name: "Ruby Rhod" };
diesel::insert_into(users)
.values(&new_user)
.execute(connection)
.unwrap();
// Insert many records
let new_users = vec![
NewUser { name: "Leeloo Multipass" },
NewUser { name: "Korben Dallas" },
];
let inserted_names = diesel::insert_into(users)
.values(&new_users)
.execute(connection)
.unwrap();
Inserting default value for a column
You can use Option<T>
to allow a column to be set to the default value when needed.
When the field is set to None
, diesel inserts the default value on supported databases.
When the field is set to Some(..)
, diesel inserts the given value.
The column color
in brands
table is NOT NULL DEFAULT 'Green'
.
#[derive(Insertable)]
#[diesel(table_name = brands)]
struct NewBrand {
color: Option<String>,
}
// Insert `Red`
let new_brand = NewBrand { color: Some("Red".into()) };
diesel::insert_into(brands)
.values(&new_brand)
.execute(connection)
.unwrap();
// Insert the default color
let new_brand = NewBrand { color: None };
diesel::insert_into(brands)
.values(&new_brand)
.execute(connection)
.unwrap();
Inserting default value for a nullable column
The column accent
in brands
table is DEFAULT 'Green'
. It is a nullable column.
You can use Option<Option<T>>
in this case.
When the field is set to None
, diesel inserts the default value on supported databases.
When the field is set to Some(None)
, diesel inserts NULL
.
When the field is set to Some(Some(..))
diesel inserts the given value.
#[derive(Insertable)]
#[diesel(table_name = brands)]
struct NewBrand {
accent: Option<Option<String>>,
}
// Insert `Red`
let new_brand = NewBrand { accent: Some(Some("Red".into())) };
diesel::insert_into(brands)
.values(&new_brand)
.execute(connection)
.unwrap();
// Insert the default accent
let new_brand = NewBrand { accent: None };
diesel::insert_into(brands)
.values(&new_brand)
.execute(connection)
.unwrap();
// Insert `NULL`
let new_brand = NewBrand { accent: Some(None) };
diesel::insert_into(brands)
.values(&new_brand)
.execute(connection)
.unwrap();
Insert from select
When inserting from a select statement,
the column list can be specified with .into_columns
.
(See also SelectStatement::insert_into
, which generally
reads better for select statements)
let new_posts = users::table
.select((
users::name.concat("'s First Post"),
users::id,
));
diesel::insert_into(posts::table)
.values(new_posts)
.into_columns((posts::title, posts::user_id))
.execute(conn)?;
let inserted_posts = posts::table
.select(posts::title)
.load::<String>(conn)?;
let expected = vec!["Sean's First Post", "Tess's First Post"];
assert_eq!(expected, inserted_posts);
With return value
let inserted_names = diesel::insert_into(users)
.values(&vec![
name.eq("Diva Plavalaguna"),
name.eq("Father Vito Cornelius"),
])
.returning(name)
.get_results(connection);
assert_eq!(Ok(vec!["Diva Plavalaguna".to_string(), "Father Vito Cornelius".to_string()]), inserted_names);