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::{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
56/// Extending [IntoSimpleExpr] to support casting ActiveEnum as TEXT in select expression
57pub trait ColumnAsExpr: IntoSimpleExpr {
58    /// Casting ActiveEnum as TEXT in select expression,
59    /// otherwise same as [IntoSimpleExpr::into_simple_expr]
60    fn into_column_as_expr(self) -> SimpleExpr;
61}
62
63macro_rules! impl_query_trait {
64    ( $trait: ident ) => {
65        impl<E> $trait for Select<E>
66        where
67            E: EntityTrait,
68        {
69            type QueryStatement = SelectStatement;
70
71            fn query(&mut self) -> &mut SelectStatement {
72                &mut self.query
73            }
74        }
75
76        impl<E, F> $trait for SelectTwo<E, F>
77        where
78            E: EntityTrait,
79            F: EntityTrait,
80        {
81            type QueryStatement = SelectStatement;
82
83            fn query(&mut self) -> &mut SelectStatement {
84                &mut self.query
85            }
86        }
87
88        impl<E, F> $trait for SelectTwoMany<E, F>
89        where
90            E: EntityTrait,
91            F: EntityTrait,
92        {
93            type QueryStatement = SelectStatement;
94
95            fn query(&mut self) -> &mut SelectStatement {
96                &mut self.query
97            }
98        }
99
100        impl<E, F, G> $trait for SelectThree<E, F, G>
101        where
102            E: EntityTrait,
103            F: EntityTrait,
104            G: EntityTrait,
105        {
106            type QueryStatement = SelectStatement;
107
108            fn query(&mut self) -> &mut SelectStatement {
109                &mut self.query
110            }
111        }
112    };
113}
114
115impl_query_trait!(QuerySelect);
116impl_query_trait!(QueryFilter);
117impl_query_trait!(QueryOrder);
118
119impl<C> ColumnAsExpr for C
120where
121    C: ColumnTrait,
122{
123    fn into_column_as_expr(self) -> SimpleExpr {
124        self.select_as(self.as_column_ref().into_column_ref().into())
125    }
126}
127
128impl ColumnAsExpr for SimpleExpr {
129    fn into_column_as_expr(self) -> SimpleExpr {
130        self.into_simple_expr()
131    }
132}
133
134impl<C> IntoSimpleExpr for C
135where
136    C: ColumnTrait,
137{
138    fn into_simple_expr(self) -> SimpleExpr {
139        SimpleExpr::Column(self.as_column_ref().into_column_ref())
140    }
141}
142
143impl IntoSimpleExpr for SimpleExpr {
144    fn into_simple_expr(self) -> SimpleExpr {
145        self
146    }
147}
148
149impl<E> Select<E>
150where
151    E: EntityTrait,
152{
153    pub(crate) fn new() -> Self {
154        Self {
155            query: SelectStatement::new(),
156            entity: PhantomData,
157        }
158        .prepare_select()
159        .prepare_from()
160    }
161
162    fn prepare_select(mut self) -> Self {
163        self.query.exprs(self.column_list());
164        self
165    }
166
167    fn column_list(&self) -> Vec<SimpleExpr> {
168        E::Column::iter()
169            .map(|col| col.select_as(col.into_expr()))
170            .collect()
171    }
172
173    fn prepare_from(mut self) -> Self {
174        self.query.from(E::default().table_ref());
175        self
176    }
177}
178
179impl<E> QueryTrait for Select<E>
180where
181    E: EntityTrait,
182{
183    type QueryStatement = SelectStatement;
184    fn query(&mut self) -> &mut SelectStatement {
185        &mut self.query
186    }
187    fn as_query(&self) -> &SelectStatement {
188        &self.query
189    }
190    fn into_query(self) -> SelectStatement {
191        self.query
192    }
193}
194
195macro_rules! select_two {
196    ( $selector: ident ) => {
197        impl<E, F> QueryTrait for $selector<E, F>
198        where
199            E: EntityTrait,
200            F: EntityTrait,
201        {
202            type QueryStatement = SelectStatement;
203            fn query(&mut self) -> &mut SelectStatement {
204                &mut self.query
205            }
206            fn as_query(&self) -> &SelectStatement {
207                &self.query
208            }
209            fn into_query(self) -> SelectStatement {
210                self.query
211            }
212        }
213    };
214}
215
216select_two!(SelectTwo);
217select_two!(SelectTwoMany);
218
219impl<E, F, G> QueryTrait for SelectThree<E, F, G>
220where
221    E: EntityTrait,
222    F: EntityTrait,
223    G: EntityTrait,
224{
225    type QueryStatement = SelectStatement;
226    fn query(&mut self) -> &mut SelectStatement {
227        &mut self.query
228    }
229    fn as_query(&self) -> &SelectStatement {
230        &self.query
231    }
232    fn into_query(self) -> SelectStatement {
233        self.query
234    }
235}
sea_orm/query/select.rs

sea_orm/query/
select.rs
