rusqlite/types/
mod.rs

1//! Traits dealing with SQLite data types.
2//!
3//! SQLite uses a [dynamic type system](https://www.sqlite.org/datatype3.html). Implementations of
4//! the [`ToSql`] and [`FromSql`] traits are provided for the basic types that
5//! SQLite provides methods for:
6//!
7//! * Strings (`String` and `&str`)
8//! * Blobs (`Vec<u8>` and `&[u8]`)
9//! * Numbers
10//!
11//! The number situation is a little complicated due to the fact that all
12//! numbers in SQLite are stored as `INTEGER` (`i64`) or `REAL` (`f64`).
13//!
14//! [`ToSql`] and [`FromSql`] are implemented for all primitive number types.
15//! [`FromSql`] has different behaviour depending on the SQL and Rust types, and
16//! the value.
17//!
18//! * `INTEGER` to integer: returns an
19//!   [`Error::IntegralValueOutOfRange`](crate::Error::IntegralValueOutOfRange)
20//!   error if the value does not fit in the Rust type.
21//! * `REAL` to integer: always returns an
22//!   [`Error::InvalidColumnType`](crate::Error::InvalidColumnType) error.
23//! * `INTEGER` to float: casts using `as` operator. Never fails.
24//! * `REAL` to float: casts using `as` operator. Never fails.
25//!
26//! [`ToSql`] always succeeds except when storing a `u64` or `usize` value that
27//! cannot fit in an `INTEGER` (`i64`). Also note that SQLite ignores column
28//! types, so if you store an `i64` in a column with type `REAL` it will be
29//! stored as an `INTEGER`, not a `REAL`.
30//!
31//! If the `time` feature is enabled, implementations are
32//! provided for `time::OffsetDateTime` that use the RFC 3339 date/time format,
33//! `"%Y-%m-%dT%H:%M:%S.%fZ"`, to store time values as strings.  These values
34//! can be parsed by SQLite's builtin
35//! [datetime](https://www.sqlite.org/lang_datefunc.html) functions.  If you
36//! want different storage for datetimes, you can use a newtype.
37#![cfg_attr(
38    feature = "time",
39    doc = r##"
40For example, to store datetimes as `i64`s counting the number of seconds since
41the Unix epoch:
42
43```
44use rusqlite::types::{FromSql, FromSqlError, FromSqlResult, ToSql, ToSqlOutput, ValueRef};
45use rusqlite::Result;
46
47pub struct DateTimeSql(pub time::OffsetDateTime);
48
49impl FromSql for DateTimeSql {
50    fn column_result(value: ValueRef) -> FromSqlResult<Self> {
51        i64::column_result(value).and_then(|as_i64| {
52            time::OffsetDateTime::from_unix_timestamp(as_i64)
53            .map(|odt| DateTimeSql(odt))
54            .map_err(|err| FromSqlError::Other(Box::new(err)))
55        })
56    }
57}
58
59impl ToSql for DateTimeSql {
60    fn to_sql(&self) -> Result<ToSqlOutput> {
61        Ok(self.0.unix_timestamp().into())
62    }
63}
64```
65
66"##
67)]
68//! [`ToSql`] and [`FromSql`] are also implemented for `Option<T>` where `T`
69//! implements [`ToSql`] or [`FromSql`] for the cases where you want to know if
70//! a value was NULL (which gets translated to `None`).
71
72pub use self::from_sql::{FromSql, FromSqlError, FromSqlResult};
73pub use self::to_sql::{ToSql, ToSqlOutput};
74pub use self::value::Value;
75pub use self::value_ref::ValueRef;
76
77use std::fmt;
78
79#[cfg(feature = "chrono")]
80#[cfg_attr(docsrs, doc(cfg(feature = "chrono")))]
81mod chrono;
82mod from_sql;
83#[cfg(feature = "serde_json")]
84#[cfg_attr(docsrs, doc(cfg(feature = "serde_json")))]
85mod serde_json;
86#[cfg(feature = "time")]
87#[cfg_attr(docsrs, doc(cfg(feature = "time")))]
88mod time;
89mod to_sql;
90#[cfg(feature = "url")]
91#[cfg_attr(docsrs, doc(cfg(feature = "url")))]
92mod url;
93mod value;
94mod value_ref;
95
96/// Empty struct that can be used to fill in a query parameter as `NULL`.
97///
98/// ## Example
99///
100/// ```rust,no_run
101/// # use rusqlite::{Connection, Result};
102/// # use rusqlite::types::{Null};
103///
104/// fn insert_null(conn: &Connection) -> Result<usize> {
105///     conn.execute("INSERT INTO people (name) VALUES (?1)", [Null])
106/// }
107/// ```
108#[derive(Copy, Clone)]
109pub struct Null;
110
111/// SQLite data types.
112/// See [Fundamental Datatypes](https://sqlite.org/c3ref/c_blob.html).
113#[derive(Clone, Debug, PartialEq, Eq)]
114pub enum Type {
115    /// NULL
116    Null,
117    /// 64-bit signed integer
118    Integer,
119    /// 64-bit IEEE floating point number
120    Real,
121    /// String
122    Text,
123    /// BLOB
124    Blob,
125}
126
127impl fmt::Display for Type {
128    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
129        match *self {
130            Type::Null => f.pad("Null"),
131            Type::Integer => f.pad("Integer"),
132            Type::Real => f.pad("Real"),
133            Type::Text => f.pad("Text"),
134            Type::Blob => f.pad("Blob"),
135        }
136    }
137}
138
139#[cfg(test)]
140mod test {
141    use super::Value;
142    use crate::{params, Connection, Error, Result, Statement};
143    use std::os::raw::{c_double, c_int};
144
145    fn checked_memory_handle() -> Result<Connection> {
146        let db = Connection::open_in_memory()?;
147        db.execute_batch("CREATE TABLE foo (b BLOB, t TEXT, i INTEGER, f FLOAT, n)")?;
148        Ok(db)
149    }
150
151    #[test]
152    fn test_blob() -> Result<()> {
153        let db = checked_memory_handle()?;
154
155        let v1234 = vec![1u8, 2, 3, 4];
156        db.execute("INSERT INTO foo(b) VALUES (?1)", [&v1234])?;
157
158        let v: Vec<u8> = db.one_column("SELECT b FROM foo")?;
159        assert_eq!(v, v1234);
160        Ok(())
161    }
162
163    #[test]
164    fn test_empty_blob() -> Result<()> {
165        let db = checked_memory_handle()?;
166
167        let empty = vec![];
168        db.execute("INSERT INTO foo(b) VALUES (?1)", [&empty])?;
169
170        let v: Vec<u8> = db.one_column("SELECT b FROM foo")?;
171        assert_eq!(v, empty);
172        Ok(())
173    }
174
175    #[test]
176    fn test_str() -> Result<()> {
177        let db = checked_memory_handle()?;
178
179        let s = "hello, world!";
180        db.execute("INSERT INTO foo(t) VALUES (?1)", [&s])?;
181
182        let from: String = db.one_column("SELECT t FROM foo")?;
183        assert_eq!(from, s);
184        Ok(())
185    }
186
187    #[test]
188    fn test_string() -> Result<()> {
189        let db = checked_memory_handle()?;
190
191        let s = "hello, world!";
192        db.execute("INSERT INTO foo(t) VALUES (?1)", [s.to_owned()])?;
193
194        let from: String = db.one_column("SELECT t FROM foo")?;
195        assert_eq!(from, s);
196        Ok(())
197    }
198
199    #[test]
200    fn test_value() -> Result<()> {
201        let db = checked_memory_handle()?;
202
203        db.execute("INSERT INTO foo(i) VALUES (?1)", [Value::Integer(10)])?;
204
205        assert_eq!(10i64, db.one_column::<i64>("SELECT i FROM foo")?);
206        Ok(())
207    }
208
209    #[test]
210    fn test_option() -> Result<()> {
211        let db = checked_memory_handle()?;
212
213        let s = Some("hello, world!");
214        let b = Some(vec![1u8, 2, 3, 4]);
215
216        db.execute("INSERT INTO foo(t) VALUES (?1)", [&s])?;
217        db.execute("INSERT INTO foo(b) VALUES (?1)", [&b])?;
218
219        let mut stmt = db.prepare("SELECT t, b FROM foo ORDER BY ROWID ASC")?;
220        let mut rows = stmt.query([])?;
221
222        {
223            let row1 = rows.next()?.unwrap();
224            let s1: Option<String> = row1.get_unwrap(0);
225            let b1: Option<Vec<u8>> = row1.get_unwrap(1);
226            assert_eq!(s.unwrap(), s1.unwrap());
227            assert!(b1.is_none());
228        }
229
230        {
231            let row2 = rows.next()?.unwrap();
232            let s2: Option<String> = row2.get_unwrap(0);
233            let b2: Option<Vec<u8>> = row2.get_unwrap(1);
234            assert!(s2.is_none());
235            assert_eq!(b, b2);
236        }
237        Ok(())
238    }
239
240    #[test]
241    #[allow(clippy::cognitive_complexity)]
242    fn test_mismatched_types() -> Result<()> {
243        fn is_invalid_column_type(err: Error) -> bool {
244            matches!(err, Error::InvalidColumnType(..))
245        }
246
247        let db = checked_memory_handle()?;
248
249        db.execute(
250            "INSERT INTO foo(b, t, i, f) VALUES (X'0102', 'text', 1, 1.5)",
251            [],
252        )?;
253
254        let mut stmt = db.prepare("SELECT b, t, i, f, n FROM foo")?;
255        let mut rows = stmt.query([])?;
256
257        let row = rows.next()?.unwrap();
258
259        // check the correct types come back as expected
260        assert_eq!(vec![1, 2], row.get::<_, Vec<u8>>(0)?);
261        assert_eq!("text", row.get::<_, String>(1)?);
262        assert_eq!(1, row.get::<_, c_int>(2)?);
263        assert!((1.5 - row.get::<_, c_double>(3)?).abs() < f64::EPSILON);
264        assert_eq!(row.get::<_, Option<c_int>>(4)?, None);
265        assert_eq!(row.get::<_, Option<c_double>>(4)?, None);
266        assert_eq!(row.get::<_, Option<String>>(4)?, None);
267
268        // check some invalid types
269
270        // 0 is actually a blob (Vec<u8>)
271        assert!(is_invalid_column_type(row.get::<_, c_int>(0).unwrap_err()));
272        assert!(is_invalid_column_type(row.get::<_, c_int>(0).unwrap_err()));
273        assert!(is_invalid_column_type(row.get::<_, i64>(0).err().unwrap()));
274        assert!(is_invalid_column_type(
275            row.get::<_, c_double>(0).unwrap_err()
276        ));
277        assert!(is_invalid_column_type(row.get::<_, String>(0).unwrap_err()));
278        #[cfg(feature = "time")]
279        assert!(is_invalid_column_type(
280            row.get::<_, time::OffsetDateTime>(0).unwrap_err()
281        ));
282        assert!(is_invalid_column_type(
283            row.get::<_, Option<c_int>>(0).unwrap_err()
284        ));
285
286        // 1 is actually a text (String)
287        assert!(is_invalid_column_type(row.get::<_, c_int>(1).unwrap_err()));
288        assert!(is_invalid_column_type(row.get::<_, i64>(1).err().unwrap()));
289        assert!(is_invalid_column_type(
290            row.get::<_, c_double>(1).unwrap_err()
291        ));
292        assert!(is_invalid_column_type(
293            row.get::<_, Vec<u8>>(1).unwrap_err()
294        ));
295        assert!(is_invalid_column_type(
296            row.get::<_, Option<c_int>>(1).unwrap_err()
297        ));
298
299        // 2 is actually an integer
300        assert!(is_invalid_column_type(row.get::<_, String>(2).unwrap_err()));
301        assert!(is_invalid_column_type(
302            row.get::<_, Vec<u8>>(2).unwrap_err()
303        ));
304        assert!(is_invalid_column_type(
305            row.get::<_, Option<String>>(2).unwrap_err()
306        ));
307
308        // 3 is actually a float (c_double)
309        assert!(is_invalid_column_type(row.get::<_, c_int>(3).unwrap_err()));
310        assert!(is_invalid_column_type(row.get::<_, i64>(3).err().unwrap()));
311        assert!(is_invalid_column_type(row.get::<_, String>(3).unwrap_err()));
312        assert!(is_invalid_column_type(
313            row.get::<_, Vec<u8>>(3).unwrap_err()
314        ));
315        assert!(is_invalid_column_type(
316            row.get::<_, Option<c_int>>(3).unwrap_err()
317        ));
318
319        // 4 is actually NULL
320        assert!(is_invalid_column_type(row.get::<_, c_int>(4).unwrap_err()));
321        assert!(is_invalid_column_type(row.get::<_, i64>(4).err().unwrap()));
322        assert!(is_invalid_column_type(
323            row.get::<_, c_double>(4).unwrap_err()
324        ));
325        assert!(is_invalid_column_type(row.get::<_, String>(4).unwrap_err()));
326        assert!(is_invalid_column_type(
327            row.get::<_, Vec<u8>>(4).unwrap_err()
328        ));
329        #[cfg(feature = "time")]
330        assert!(is_invalid_column_type(
331            row.get::<_, time::OffsetDateTime>(4).unwrap_err()
332        ));
333        Ok(())
334    }
335
336    #[test]
337    fn test_dynamic_type() -> Result<()> {
338        use super::Value;
339        let db = checked_memory_handle()?;
340
341        db.execute(
342            "INSERT INTO foo(b, t, i, f) VALUES (X'0102', 'text', 1, 1.5)",
343            [],
344        )?;
345
346        let mut stmt = db.prepare("SELECT b, t, i, f, n FROM foo")?;
347        let mut rows = stmt.query([])?;
348
349        let row = rows.next()?.unwrap();
350        assert_eq!(Value::Blob(vec![1, 2]), row.get::<_, Value>(0)?);
351        assert_eq!(Value::Text(String::from("text")), row.get::<_, Value>(1)?);
352        assert_eq!(Value::Integer(1), row.get::<_, Value>(2)?);
353        match row.get::<_, Value>(3)? {
354            Value::Real(val) => assert!((1.5 - val).abs() < f64::EPSILON),
355            x => panic!("Invalid Value {:?}", x),
356        }
357        assert_eq!(Value::Null, row.get::<_, Value>(4)?);
358        Ok(())
359    }
360
361    macro_rules! test_conversion {
362        ($db_etc:ident, $insert_value:expr, $get_type:ty,expect $expected_value:expr) => {
363            $db_etc.insert_statement.execute(params![$insert_value])?;
364            let res = $db_etc
365                .query_statement
366                .query_row([], |row| row.get::<_, $get_type>(0));
367            assert_eq!(res?, $expected_value);
368            $db_etc.delete_statement.execute([])?;
369        };
370        ($db_etc:ident, $insert_value:expr, $get_type:ty,expect_from_sql_error) => {
371            $db_etc.insert_statement.execute(params![$insert_value])?;
372            let res = $db_etc
373                .query_statement
374                .query_row([], |row| row.get::<_, $get_type>(0));
375            res.unwrap_err();
376            $db_etc.delete_statement.execute([])?;
377        };
378        ($db_etc:ident, $insert_value:expr, $get_type:ty,expect_to_sql_error) => {
379            $db_etc
380                .insert_statement
381                .execute(params![$insert_value])
382                .unwrap_err();
383        };
384    }
385
386    #[test]
387    fn test_numeric_conversions() -> Result<()> {
388        #![allow(clippy::float_cmp)]
389
390        // Test what happens when we store an f32 and retrieve an i32 etc.
391        let db = Connection::open_in_memory()?;
392        db.execute_batch("CREATE TABLE foo (x)")?;
393
394        // SQLite actually ignores the column types, so we just need to test
395        // different numeric values.
396
397        struct DbEtc<'conn> {
398            insert_statement: Statement<'conn>,
399            query_statement: Statement<'conn>,
400            delete_statement: Statement<'conn>,
401        }
402
403        let mut db_etc = DbEtc {
404            insert_statement: db.prepare("INSERT INTO foo VALUES (?1)")?,
405            query_statement: db.prepare("SELECT x FROM foo")?,
406            delete_statement: db.prepare("DELETE FROM foo")?,
407        };
408
409        // Basic non-converting test.
410        test_conversion!(db_etc, 0u8, u8, expect 0u8);
411
412        // In-range integral conversions.
413        test_conversion!(db_etc, 100u8, i8, expect 100i8);
414        test_conversion!(db_etc, 200u8, u8, expect 200u8);
415        test_conversion!(db_etc, 100u16, i8, expect 100i8);
416        test_conversion!(db_etc, 200u16, u8, expect 200u8);
417        test_conversion!(db_etc, u32::MAX, u64, expect u32::MAX as u64);
418        test_conversion!(db_etc, i64::MIN, i64, expect i64::MIN);
419        test_conversion!(db_etc, i64::MAX, i64, expect i64::MAX);
420        test_conversion!(db_etc, i64::MAX, u64, expect i64::MAX as u64);
421        test_conversion!(db_etc, 100usize, usize, expect 100usize);
422        test_conversion!(db_etc, 100u64, u64, expect 100u64);
423        test_conversion!(db_etc, i64::MAX as u64, u64, expect i64::MAX as u64);
424
425        // Out-of-range integral conversions.
426        test_conversion!(db_etc, 200u8, i8, expect_from_sql_error);
427        test_conversion!(db_etc, 400u16, i8, expect_from_sql_error);
428        test_conversion!(db_etc, 400u16, u8, expect_from_sql_error);
429        test_conversion!(db_etc, -1i8, u8, expect_from_sql_error);
430        test_conversion!(db_etc, i64::MIN, u64, expect_from_sql_error);
431        test_conversion!(db_etc, u64::MAX, i64, expect_to_sql_error);
432        test_conversion!(db_etc, u64::MAX, u64, expect_to_sql_error);
433        test_conversion!(db_etc, i64::MAX as u64 + 1, u64, expect_to_sql_error);
434
435        // FromSql integer to float, always works.
436        test_conversion!(db_etc, i64::MIN, f32, expect i64::MIN as f32);
437        test_conversion!(db_etc, i64::MAX, f32, expect i64::MAX as f32);
438        test_conversion!(db_etc, i64::MIN, f64, expect i64::MIN as f64);
439        test_conversion!(db_etc, i64::MAX, f64, expect i64::MAX as f64);
440
441        // FromSql float to int conversion, never works even if the actual value
442        // is an integer.
443        test_conversion!(db_etc, 0f64, i64, expect_from_sql_error);
444        Ok(())
445    }
446}
rusqlite/types/mod.rs

rusqlite/types/
mod.rs
