sea_orm/query/
select.rs

1use crate::{ColumnTrait, EntityTrait, Iterable, QueryFilter, QueryOrder, QuerySelect, QueryTrait};
2use core::fmt::Debug;
3use core::marker::PhantomData;
4use sea_query::{Expr, IntoColumnRef, SelectStatement, SimpleExpr};
5
6/// Defines a structure to perform select operations
7#[derive(Clone, Debug)]
8pub struct Select<E>
9where
10    E: EntityTrait,
11{
12    pub(crate) query: SelectStatement,
13    pub(crate) entity: PhantomData<E>,
14}
15
16/// Defines a structure to perform a SELECT operation on two Models
17#[derive(Clone, Debug)]
18pub struct SelectTwo<E, F>
19where
20    E: EntityTrait,
21    F: EntityTrait,
22{
23    pub(crate) query: SelectStatement,
24    pub(crate) entity: PhantomData<(E, F)>,
25}
26
27/// Defines a structure to perform a SELECT operation on many Models
28#[derive(Clone, Debug)]
29pub struct SelectTwoMany<E, F>
30where
31    E: EntityTrait,
32    F: EntityTrait,
33{
34    pub(crate) query: SelectStatement,
35    pub(crate) entity: PhantomData<(E, F)>,
36}
37
38/// Performs a conversion to [SimpleExpr]
39pub trait IntoSimpleExpr {
40    /// Method to perform the conversion
41    fn into_simple_expr(self) -> SimpleExpr;
42}
43
44macro_rules! impl_trait {
45    ( $trait: ident ) => {
46        impl<E> $trait for Select<E>
47        where
48            E: EntityTrait,
49        {
50            type QueryStatement = SelectStatement;
51
52            fn query(&mut self) -> &mut SelectStatement {
53                &mut self.query
54            }
55        }
56
57        impl<E, F> $trait for SelectTwo<E, F>
58        where
59            E: EntityTrait,
60            F: EntityTrait,
61        {
62            type QueryStatement = SelectStatement;
63
64            fn query(&mut self) -> &mut SelectStatement {
65                &mut self.query
66            }
67        }
68
69        impl<E, F> $trait for SelectTwoMany<E, F>
70        where
71            E: EntityTrait,
72            F: EntityTrait,
73        {
74            type QueryStatement = SelectStatement;
75
76            fn query(&mut self) -> &mut SelectStatement {
77                &mut self.query
78            }
79        }
80    };
81}
82
83impl_trait!(QuerySelect);
84impl_trait!(QueryFilter);
85impl_trait!(QueryOrder);
86
87impl<C> IntoSimpleExpr for C
88where
89    C: ColumnTrait,
90{
91    fn into_simple_expr(self) -> SimpleExpr {
92        SimpleExpr::Column(self.as_column_ref().into_column_ref())
93    }
94}
95
96impl IntoSimpleExpr for Expr {
97    fn into_simple_expr(self) -> SimpleExpr {
98        self.into()
99    }
100}
101
102impl IntoSimpleExpr for SimpleExpr {
103    fn into_simple_expr(self) -> SimpleExpr {
104        self
105    }
106}
107
108impl<E> Select<E>
109where
110    E: EntityTrait,
111{
112    pub(crate) fn new() -> Self {
113        Self {
114            query: SelectStatement::new(),
115            entity: PhantomData,
116        }
117        .prepare_select()
118        .prepare_from()
119    }
120
121    fn prepare_select(mut self) -> Self {
122        self.query.exprs(self.column_list());
123        self
124    }
125
126    fn column_list(&self) -> Vec<SimpleExpr> {
127        E::Column::iter()
128            .map(|col| col.select_as(col.into_expr()))
129            .collect()
130    }
131
132    fn prepare_from(mut self) -> Self {
133        self.query.from(E::default().table_ref());
134        self
135    }
136}
137
138impl<E> QueryTrait for Select<E>
139where
140    E: EntityTrait,
141{
142    type QueryStatement = SelectStatement;
143    fn query(&mut self) -> &mut SelectStatement {
144        &mut self.query
145    }
146    fn as_query(&self) -> &SelectStatement {
147        &self.query
148    }
149    fn into_query(self) -> SelectStatement {
150        self.query
151    }
152}
153
154macro_rules! select_two {
155    ( $selector: ident ) => {
156        impl<E, F> QueryTrait for $selector<E, F>
157        where
158            E: EntityTrait,
159            F: EntityTrait,
160        {
161            type QueryStatement = SelectStatement;
162            fn query(&mut self) -> &mut SelectStatement {
163                &mut self.query
164            }
165            fn as_query(&self) -> &SelectStatement {
166                &self.query
167            }
168            fn into_query(self) -> SelectStatement {
169                self.query
170            }
171        }
172    };
173}
174
175select_two!(SelectTwo);
176select_two!(SelectTwoMany);
sea_orm/query/select.rs

sea_orm/query/
select.rs
