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
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
use std::marker::PhantomData;

use super::Query;
use crate::backend::Backend;
use crate::connection::Connection;
use crate::query_builder::{AstPass, QueryFragment, QueryId};
use crate::query_dsl::RunQueryDsl;
use crate::result::QueryResult;
use crate::serialize::ToSql;
use crate::sql_types::{HasSqlType, Untyped};

#[derive(Debug, Clone)]
#[must_use = "Queries are only executed when calling `load`, `get_result` or similar."]
/// The return value of `sql_query`.
///
/// Unlike most queries in Diesel, `SqlQuery` loads its data by column name,
/// rather than by index. This means that you cannot deserialize this query into
/// a tuple, and any structs used must implement `QueryableByName`.
///
/// See [`sql_query`](crate::sql_query()) for examples.
pub struct SqlQuery<Inner = ()> {
    inner: Inner,
    query: String,
}

impl<Inner> SqlQuery<Inner> {
    pub(crate) fn new(inner: Inner, query: String) -> Self {
        SqlQuery { inner, query }
    }

    /// Bind a value for use with this SQL query. The given query should have
    /// placeholders that vary based on the database type,
    /// like [SQLite Parameter](https://sqlite.org/lang_expr.html#varparam) syntax,
    /// [PostgreSQL PREPARE syntax](https://www.postgresql.org/docs/current/sql-prepare.html),
    /// or [MySQL bind syntax](https://dev.mysql.com/doc/refman/8.0/en/mysql-stmt-bind-param.html).
    ///
    /// # Safety
    ///
    /// This function should be used with care, as Diesel cannot validate that
    /// the value is of the right type nor can it validate that you have passed
    /// the correct number of parameters.
    ///
    /// # Example
    ///
    /// ```
    /// # include!("../doctest_setup.rs");
    /// #
    /// # use schema::users;
    /// #
    /// # #[derive(QueryableByName, Debug, PartialEq)]
    /// # #[table_name="users"]
    /// # struct User {
    /// #     id: i32,
    /// #     name: String,
    /// # }
    /// #
    /// # fn main() {
    /// #     use diesel::sql_query;
    /// #     use diesel::sql_types::{Integer, Text};
    /// #
    /// #     let connection = &mut establish_connection();
    /// #     diesel::insert_into(users::table)
    /// #         .values(users::name.eq("Jim"))
    /// #         .execute(connection).unwrap();
    /// # #[cfg(feature = "postgres")]
    /// # let users = sql_query("SELECT * FROM users WHERE id > $1 AND name != $2");
    /// # #[cfg(not(feature = "postgres"))]
    /// let users = sql_query("SELECT * FROM users WHERE id > ? AND name <> ?")
    /// # ;
    /// # let users = users
    ///     .bind::<Integer, _>(1)
    ///     .bind::<Text, _>("Tess")
    ///     .get_results(connection);
    /// let expected_users = vec![
    ///     User { id: 3, name: "Jim".into() },
    /// ];
    /// assert_eq!(Ok(expected_users), users);
    /// # }
    /// ```
    pub fn bind<ST, Value>(self, value: Value) -> UncheckedBind<Self, Value, ST> {
        UncheckedBind::new(self, value)
    }

    /// Internally boxes future calls on `bind` and `sql` so that they don't
    /// change the type.
    ///
    /// This allows doing things you otherwise couldn't do, e.g. `bind`ing in a
    /// loop.
    pub fn into_boxed<'f, DB: Backend>(self) -> BoxedSqlQuery<'f, DB, Self> {
        BoxedSqlQuery::new(self)
    }

    /// Appends a piece of SQL code at the end.
    pub fn sql<T: AsRef<str>>(mut self, sql: T) -> Self {
        self.query += sql.as_ref();
        self
    }
}

impl<DB, Inner> QueryFragment<DB> for SqlQuery<Inner>
where
    DB: Backend,
    Inner: QueryFragment<DB>,
{
    fn walk_ast(&self, mut out: AstPass<DB>) -> QueryResult<()> {
        out.unsafe_to_cache_prepared();
        self.inner.walk_ast(out.reborrow())?;
        out.push_sql(&self.query);
        Ok(())
    }
}

impl<Inner> QueryId for SqlQuery<Inner> {
    type QueryId = ();

    const HAS_STATIC_QUERY_ID: bool = false;
}

impl<Inner> Query for SqlQuery<Inner> {
    type SqlType = Untyped;
}

impl<Inner, Conn> RunQueryDsl<Conn> for SqlQuery<Inner> {}

#[derive(Debug, Clone, Copy)]
#[must_use = "Queries are only executed when calling `load`, `get_result` or similar."]
/// Returned by the [`SqlQuery::bind()`] method when binding a value to a fragment of SQL.
///
pub struct UncheckedBind<Query, Value, ST> {
    query: Query,
    value: Value,
    _marker: PhantomData<ST>,
}

impl<Query, Value, ST> UncheckedBind<Query, Value, ST> {
    pub fn new(query: Query, value: Value) -> Self {
        UncheckedBind {
            query,
            value,
            _marker: PhantomData,
        }
    }

    pub fn bind<ST2, Value2>(self, value: Value2) -> UncheckedBind<Self, Value2, ST2> {
        UncheckedBind::new(self, value)
    }

    pub fn into_boxed<'f, DB: Backend>(self) -> BoxedSqlQuery<'f, DB, Self> {
        BoxedSqlQuery::new(self)
    }

    /// Construct a full SQL query using raw SQL.
    ///
    /// This function exists for cases where a query needs to be written that is not
    /// supported by the query builder. Unlike most queries in Diesel, `sql_query`
    /// will deserialize its data by name, not by index. That means that you cannot
    /// deserialize into a tuple, and structs which you deserialize from this
    /// function will need to have `#[derive(QueryableByName)]`.
    ///
    /// This function is intended for use when you want to write the entire query
    /// using raw SQL. If you only need a small bit of raw SQL in your query, use
    /// [`sql`](dsl::sql()) instead.
    ///
    /// Query parameters can be bound into the raw query using [`SqlQuery::bind()`].
    ///
    /// # Safety
    ///
    /// The implementation of `QueryableByName` will assume that columns with a
    /// given name will have a certain type. The compiler will be unable to verify
    /// that the given type is correct. If your query returns a column of an
    /// unexpected type, the result may have the wrong value, or return an error.
    ///
    /// # Examples
    ///
    /// ```rust
    /// # include!("../doctest_setup.rs");
    /// #
    /// # use schema::users;
    /// #
    /// # #[derive(QueryableByName, Debug, PartialEq)]
    /// # #[table_name="users"]
    /// # struct User {
    /// #     id: i32,
    /// #     name: String,
    /// # }
    /// #
    /// # fn main() {
    /// #     use diesel::sql_query;
    /// #     use diesel::sql_types::{Integer, Text};
    /// #
    /// #     let connection = &mut establish_connection();
    /// #     diesel::insert_into(users::table)
    /// #         .values(users::name.eq("Jim"))
    /// #         .execute(connection).unwrap();
    /// # #[cfg(feature = "postgres")]
    /// # let users = sql_query("SELECT * FROM users WHERE id > $1 AND name != $2");
    /// # #[cfg(not(feature = "postgres"))]
    /// let users = sql_query("SELECT * FROM users WHERE id > ? AND name <> ?")
    /// # ;
    /// # let users = users
    ///     .bind::<Integer, _>(1)
    ///     .bind::<Text, _>("Tess")
    ///     .get_results(connection);
    /// let expected_users = vec![
    ///     User { id: 3, name: "Jim".into() },
    /// ];
    /// assert_eq!(Ok(expected_users), users);
    /// # }
    /// ```
    /// [`SqlQuery::bind()`]: query_builder::SqlQuery::bind()
    pub fn sql<T: Into<String>>(self, sql: T) -> SqlQuery<Self> {
        SqlQuery::new(self, sql.into())
    }
}

impl<Query, Value, ST> QueryId for UncheckedBind<Query, Value, ST>
where
    Query: QueryId,
    ST: QueryId,
{
    type QueryId = UncheckedBind<Query::QueryId, (), ST::QueryId>;

    const HAS_STATIC_QUERY_ID: bool = Query::HAS_STATIC_QUERY_ID && ST::HAS_STATIC_QUERY_ID;
}

impl<Query, Value, ST, DB> QueryFragment<DB> for UncheckedBind<Query, Value, ST>
where
    DB: Backend + HasSqlType<ST>,
    Query: QueryFragment<DB>,
    Value: ToSql<ST, DB>,
{
    fn walk_ast(&self, mut out: AstPass<DB>) -> QueryResult<()> {
        self.query.walk_ast(out.reborrow())?;
        out.push_bind_param_value_only(&self.value)?;
        Ok(())
    }
}

impl<Q, Value, ST> Query for UncheckedBind<Q, Value, ST> {
    type SqlType = Untyped;
}

impl<Conn, Query, Value, ST> RunQueryDsl<Conn> for UncheckedBind<Query, Value, ST> {}

#[must_use = "Queries are only executed when calling `load`, `get_result`, or similar."]
/// See [`SqlQuery::into_boxed`].
///
/// [`SqlQuery::into_boxed`]: SqlQuery::into_boxed()
#[allow(missing_debug_implementations)]
pub struct BoxedSqlQuery<'f, DB: Backend, Query> {
    query: Query,
    sql: String,
    binds: Vec<Box<dyn Fn(AstPass<DB>) -> QueryResult<()> + 'f>>,
}

impl<'f, DB: Backend, Query> BoxedSqlQuery<'f, DB, Query> {
    pub(crate) fn new(query: Query) -> Self {
        BoxedSqlQuery {
            query,
            sql: "".to_string(),
            binds: vec![],
        }
    }

    /// See [`SqlQuery::bind`].
    ///
    /// [`SqlQuery::bind`]: SqlQuery::bind()
    pub fn bind<BindSt, Value>(mut self, b: Value) -> Self
    where
        DB: HasSqlType<BindSt>,
        Value: ToSql<BindSt, DB> + 'f,
    {
        self.binds
            .push(Box::new(move |mut out| out.push_bind_param_value_only(&b)));
        self
    }

    /// See [`SqlQuery::sql`].
    ///
    /// [`SqlQuery::sql`]: SqlQuery::sql()
    pub fn sql<T: AsRef<str>>(mut self, sql: T) -> Self {
        self.sql += sql.as_ref();
        self
    }
}

impl<DB, Query> QueryFragment<DB> for BoxedSqlQuery<'_, DB, Query>
where
    DB: Backend,
    Query: QueryFragment<DB>,
{
    fn walk_ast(&self, mut out: AstPass<DB>) -> QueryResult<()> {
        out.unsafe_to_cache_prepared();
        self.query.walk_ast(out.reborrow())?;
        out.push_sql(&self.sql);

        for b in &self.binds {
            b(out.reborrow())?;
        }
        Ok(())
    }
}

impl<DB: Backend, Query> QueryId for BoxedSqlQuery<'_, DB, Query> {
    type QueryId = ();

    const HAS_STATIC_QUERY_ID: bool = false;
}

impl<DB, Q> Query for BoxedSqlQuery<'_, DB, Q>
where
    DB: Backend,
{
    type SqlType = Untyped;
}

impl<Conn: Connection, Query> RunQueryDsl<Conn> for BoxedSqlQuery<'_, Conn::Backend, Query> {}