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/// Defines a structure to perform a SELECT operation on two Models
39#[derive(Clone, Debug)]
40pub struct SelectThree<E, F, G>
41where
42    E: EntityTrait,
43    F: EntityTrait,
44    G: EntityTrait,
45{
46    pub(crate) query: SelectStatement,
47    pub(crate) entity: PhantomData<(E, F, G)>,
48}
49
50/// Performs a conversion to [SimpleExpr]
51pub trait IntoSimpleExpr {
52    /// Method to perform the conversion
53    fn into_simple_expr(self) -> SimpleExpr;
54}
55
56macro_rules! impl_query_trait {
57    ( $trait: ident ) => {
58        impl<E> $trait for Select<E>
59        where
60            E: 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 SelectTwo<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        impl<E, F> $trait for SelectTwoMany<E, F>
82        where
83            E: EntityTrait,
84            F: EntityTrait,
85        {
86            type QueryStatement = SelectStatement;
87
88            fn query(&mut self) -> &mut SelectStatement {
89                &mut self.query
90            }
91        }
92
93        impl<E, F, G> $trait for SelectThree<E, F, G>
94        where
95            E: EntityTrait,
96            F: EntityTrait,
97            G: EntityTrait,
98        {
99            type QueryStatement = SelectStatement;
100
101            fn query(&mut self) -> &mut SelectStatement {
102                &mut self.query
103            }
104        }
105    };
106}
107
108impl_query_trait!(QuerySelect);
109impl_query_trait!(QueryFilter);
110impl_query_trait!(QueryOrder);
111
112impl<C> IntoSimpleExpr for C
113where
114    C: ColumnTrait,
115{
116    fn into_simple_expr(self) -> SimpleExpr {
117        SimpleExpr::Column(self.as_column_ref().into_column_ref())
118    }
119}
120
121impl IntoSimpleExpr for Expr {
122    fn into_simple_expr(self) -> SimpleExpr {
123        self.into()
124    }
125}
126
127impl IntoSimpleExpr for SimpleExpr {
128    fn into_simple_expr(self) -> SimpleExpr {
129        self
130    }
131}
132
133impl<E> Select<E>
134where
135    E: EntityTrait,
136{
137    pub(crate) fn new() -> Self {
138        Self {
139            query: SelectStatement::new(),
140            entity: PhantomData,
141        }
142        .prepare_select()
143        .prepare_from()
144    }
145
146    fn prepare_select(mut self) -> Self {
147        self.query.exprs(self.column_list());
148        self
149    }
150
151    fn column_list(&self) -> Vec<SimpleExpr> {
152        E::Column::iter()
153            .map(|col| col.select_as(col.into_expr()))
154            .collect()
155    }
156
157    fn prepare_from(mut self) -> Self {
158        self.query.from(E::default().table_ref());
159        self
160    }
161}
162
163impl<E> QueryTrait for Select<E>
164where
165    E: EntityTrait,
166{
167    type QueryStatement = SelectStatement;
168    fn query(&mut self) -> &mut SelectStatement {
169        &mut self.query
170    }
171    fn as_query(&self) -> &SelectStatement {
172        &self.query
173    }
174    fn into_query(self) -> SelectStatement {
175        self.query
176    }
177}
178
179macro_rules! select_two {
180    ( $selector: ident ) => {
181        impl<E, F> QueryTrait for $selector<E, F>
182        where
183            E: EntityTrait,
184            F: EntityTrait,
185        {
186            type QueryStatement = SelectStatement;
187            fn query(&mut self) -> &mut SelectStatement {
188                &mut self.query
189            }
190            fn as_query(&self) -> &SelectStatement {
191                &self.query
192            }
193            fn into_query(self) -> SelectStatement {
194                self.query
195            }
196        }
197    };
198}
199
200select_two!(SelectTwo);
201select_two!(SelectTwoMany);
202
203impl<E, F, G> QueryTrait for SelectThree<E, F, G>
204where
205    E: EntityTrait,
206    F: EntityTrait,
207    G: EntityTrait,
208{
209    type QueryStatement = SelectStatement;
210    fn query(&mut self) -> &mut SelectStatement {
211        &mut self.query
212    }
213    fn as_query(&self) -> &SelectStatement {
214        &self.query
215    }
216    fn into_query(self) -> SelectStatement {
217        self.query
218    }
219}
sea_orm/query/select.rs

sea_orm/query/
select.rs
