use crate::backend::Backend;
use crate::expression::{Expression, NonAggregate, SelectableExpression};
use crate::insertable::*;
use crate::query_builder::*;
use crate::query_source::Table;
#[derive(Debug, Clone, Copy, QueryId)]
pub struct InsertFromSelect<Select, Columns> {
pub(in crate::query_builder) query: Select,
pub(in crate::query_builder) columns: Columns,
}
impl<Select, Columns> InsertFromSelect<Select, Columns> {
pub fn new<T>(query: Select) -> Self
where
T: Table<AllColumns = Columns>,
Columns: SelectableExpression<T> + NonAggregate,
{
Self {
query,
columns: T::all_columns(),
}
}
pub fn with_columns<C>(self, columns: C) -> InsertFromSelect<Select, C> {
InsertFromSelect {
query: self.query,
columns,
}
}
}
impl<DB, Select, Columns> CanInsertInSingleQuery<DB> for InsertFromSelect<Select, Columns>
where
DB: Backend,
{
fn rows_to_insert(&self) -> Option<usize> {
None
}
}
impl<DB, Select, Columns> QueryFragment<DB> for InsertFromSelect<Select, Columns>
where
DB: Backend,
Columns: ColumnList + Expression,
Select: Query<SqlType = Columns::SqlType> + QueryFragment<DB>,
{
fn walk_ast<'b>(&'b self, mut out: AstPass<'_, 'b, DB>) -> QueryResult<()> {
out.push_sql("(");
self.columns.walk_ast(out.reborrow())?;
out.push_sql(") ");
self.query.walk_ast(out.reborrow())?;
Ok(())
}
}
impl<Select, Columns> UndecoratedInsertRecord<Columns::Table> for InsertFromSelect<Select, Columns>
where
Columns: ColumnList + Expression,
Select: Query<SqlType = Columns::SqlType>,
{
}