1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
use crate::ast::{Column, ConditionTree, Expression, Query, Table};
type Type<'a> = Column<'a>;
/// A builder for an `UPDATE` statement.
#[derive(Debug, PartialEq, Clone)]
pub struct Update<'a> {
pub(crate) table: Table<'a>,
pub(crate) columns: Vec<Column<'a>>,
pub(crate) values: Vec<Expression<'a>>,
pub(crate) conditions: Option<ConditionTree<'a>>,
pub(crate) returning: Option<Vec<Type<'a>>>,
}
impl<'a> From<Update<'a>> for Query<'a> {
fn from(update: Update<'a>) -> Self {
Query::Update(Box::new(update))
}
}
impl<'a> Update<'a> {
/// Creates the basis for an `UPDATE` statement to the given table.
pub fn table<T>(table: T) -> Self
where
T: Into<Table<'a>>,
{
Self {
table: table.into(),
columns: Vec::new(),
values: Vec::new(),
conditions: None,
returning: None,
}
}
/// Add another column value assignment to the query
///
/// ```rust
/// # use grafbase_sql_ast::{ast::*, renderer::{Renderer, self}};
/// # fn main() {
/// let mut query = Update::table("users");
/// query.set("foo", 10);
/// query.set("bar", false);
///
/// let (sql, params) = renderer::Postgres::build(query);
/// assert_eq!(r#"UPDATE "users" SET "foo" = $1, "bar" = $2"#, sql);
///
/// assert_eq!(
/// vec![
/// Value::from(10),
/// Value::from(false),
/// ],
/// params,
/// );
/// # }
/// ```
pub fn set<K, V>(&mut self, column: K, value: V)
where
K: Into<Column<'a>>,
V: Into<Expression<'a>>,
{
self.columns.push(column.into());
self.values.push(value.into());
}
/// Adds `WHERE` conditions to the query. See
/// [Comparable](trait.Comparable.html#required-methods) for more examples.
///
/// ```rust
/// # use grafbase_sql_ast::{ast::*, renderer::{Renderer, self}};
/// # fn main() {
/// let mut query = Update::table("users");
/// query.set("foo", 1);
/// query.so_that("bar".equals(false));
///
/// let (sql, params) = renderer::Postgres::build(query);
///
/// assert_eq!(r#"UPDATE "users" SET "foo" = $1 WHERE "bar" = $2"#, sql);
///
/// assert_eq!(
/// vec![
/// Value::from(1),
/// Value::from(false),
/// ],
/// params,
/// );
/// # }
/// ```
///
/// We can also use a nested `SELECT` in the conditions.
///
/// ```rust
/// # use grafbase_sql_ast::{ast::*, renderer::{Renderer, self}};
/// # fn main() {
/// let mut select = Select::from_table("bars");
/// select.column("id");
/// select.so_that("uniq_val".equals(3));
///
/// let mut query = Update::table("users");
/// query.set("foo", 1);
/// query.so_that("bar".equals(select));
///
/// let (sql, params) = renderer::Postgres::build(query);
///
/// assert_eq!(
/// r#"UPDATE "users" SET "foo" = $1 WHERE "bar" = (SELECT "id" FROM "bars" WHERE "uniq_val" = $2)"#,
/// sql
/// );
///
/// assert_eq!(
/// vec![
/// Value::from(1),
/// Value::from(3),
/// ],
/// params,
/// );
/// # }
/// ```
pub fn so_that<T>(&mut self, conditions: T)
where
T: Into<ConditionTree<'a>>,
{
self.conditions = Some(conditions.into());
}
/// Sets the returned columns.
///
/// ```rust
/// # use grafbase_sql_ast::{ast::*, renderer::{Renderer, self}};
/// # fn main() {
/// let mut update = Update::table("users");
/// update.set("foo", 10);
/// update.returning(vec!["id"]);
///
/// let (sql, _) = renderer::Postgres::build(update);
///
/// assert_eq!(r#"UPDATE "users" SET "foo" = $1 RETURNING "id""#, sql);
/// # }
/// ```
#[cfg(feature = "postgresql")]
pub fn returning<K, I>(&mut self, columns: I)
where
K: Into<Column<'a>>,
I: IntoIterator<Item = K>,
{
self.returning = Some(columns.into_iter().map(|k| k.into()).collect());
}
}