rusqlite/
statement.rs

1use std::os::raw::{c_int, c_void};
2#[cfg(feature = "array")]
3use std::rc::Rc;
4use std::slice::from_raw_parts;
5use std::{fmt, mem, ptr, str};
6
7use super::ffi;
8use super::{len_as_c_int, str_for_sqlite};
9use super::{
10    AndThenRows, Connection, Error, MappedRows, Params, RawStatement, Result, Row, Rows, ValueRef,
11};
12use crate::types::{ToSql, ToSqlOutput};
13#[cfg(feature = "array")]
14use crate::vtab::array::{free_array, ARRAY_TYPE};
15
16/// A prepared statement.
17pub struct Statement<'conn> {
18    conn: &'conn Connection,
19    pub(crate) stmt: RawStatement,
20}
21
22impl Statement<'_> {
23    /// Execute the prepared statement.
24    ///
25    /// On success, returns the number of rows that were changed or inserted or
26    /// deleted (via `sqlite3_changes`).
27    ///
28    /// ## Example
29    ///
30    /// ### Use with positional parameters
31    ///
32    /// ```rust,no_run
33    /// # use rusqlite::{Connection, Result, params};
34    /// fn update_rows(conn: &Connection) -> Result<()> {
35    ///     let mut stmt = conn.prepare("UPDATE foo SET bar = ?1 WHERE qux = ?2")?;
36    ///     // For a single parameter, or a parameter where all the values have
37    ///     // the same type, just passing an array is simplest.
38    ///     stmt.execute([2i32])?;
39    ///     // The `rusqlite::params!` macro is mostly useful when the parameters do not
40    ///     // all have the same type, or if there are more than 32 parameters
41    ///     // at once, but it can be used in other cases.
42    ///     stmt.execute(params![1i32])?;
43    ///     // However, it's not required, many cases are fine as:
44    ///     stmt.execute(&[&2i32])?;
45    ///     // Or even:
46    ///     stmt.execute([2i32])?;
47    ///     // If you really want to, this is an option as well.
48    ///     stmt.execute((2i32,))?;
49    ///     Ok(())
50    /// }
51    /// ```
52    ///
53    /// #### Heterogeneous positional parameters
54    ///
55    /// ```
56    /// use rusqlite::{Connection, Result};
57    /// fn store_file(conn: &Connection, path: &str, data: &[u8]) -> Result<()> {
58    ///     # // no need to do it for real.
59    ///     # fn sha256(_: &[u8]) -> [u8; 32] { [0; 32] }
60    ///     let query = "INSERT OR REPLACE INTO files(path, hash, data) VALUES (?1, ?2, ?3)";
61    ///     let mut stmt = conn.prepare_cached(query)?;
62    ///     let hash: [u8; 32] = sha256(data);
63    ///     // The easiest way to pass positional parameters of have several
64    ///     // different types is by using a tuple.
65    ///     stmt.execute((path, hash, data))?;
66    ///     // Using the `params!` macro also works, and supports longer parameter lists:
67    ///     stmt.execute(rusqlite::params![path, hash, data])?;
68    ///     Ok(())
69    /// }
70    /// # let c = Connection::open_in_memory().unwrap();
71    /// # c.execute_batch("CREATE TABLE files(path TEXT PRIMARY KEY, hash BLOB, data BLOB)").unwrap();
72    /// # store_file(&c, "foo/bar.txt", b"bibble").unwrap();
73    /// # store_file(&c, "foo/baz.txt", b"bobble").unwrap();
74    /// ```
75    ///
76    /// ### Use with named parameters
77    ///
78    /// ```rust,no_run
79    /// # use rusqlite::{Connection, Result, named_params};
80    /// fn insert(conn: &Connection) -> Result<()> {
81    ///     let mut stmt = conn.prepare("INSERT INTO test (key, value) VALUES (:key, :value)")?;
82    ///     // The `rusqlite::named_params!` macro (like `params!`) is useful for heterogeneous
83    ///     // sets of parameters (where all parameters are not the same type), or for queries
84    ///     // with many (more than 32) statically known parameters.
85    ///     stmt.execute(named_params! { ":key": "one", ":val": 2 })?;
86    ///     // However, named parameters can also be passed like:
87    ///     stmt.execute(&[(":key", "three"), (":val", "four")])?;
88    ///     // Or even: (note that a &T is required for the value type, currently)
89    ///     stmt.execute(&[(":key", &100), (":val", &200)])?;
90    ///     Ok(())
91    /// }
92    /// ```
93    ///
94    /// ### Use without parameters
95    ///
96    /// ```rust,no_run
97    /// # use rusqlite::{Connection, Result, params};
98    /// fn delete_all(conn: &Connection) -> Result<()> {
99    ///     let mut stmt = conn.prepare("DELETE FROM users")?;
100    ///     stmt.execute([])?;
101    ///     Ok(())
102    /// }
103    /// ```
104    ///
105    /// # Failure
106    ///
107    /// Will return `Err` if binding parameters fails, the executed statement
108    /// returns rows (in which case `query` should be used instead), or the
109    /// underlying SQLite call fails.
110    #[inline]
111    pub fn execute<P: Params>(&mut self, params: P) -> Result<usize> {
112        params.__bind_in(self)?;
113        self.execute_with_bound_parameters()
114    }
115
116    /// Execute an INSERT and return the ROWID.
117    ///
118    /// # Note
119    ///
120    /// This function is a convenience wrapper around
121    /// [`execute()`](Statement::execute) intended for queries that insert a
122    /// single item. It is possible to misuse this function in a way that it
123    /// cannot detect, such as by calling it on a statement which _updates_
124    /// a single item rather than inserting one. Please don't do that.
125    ///
126    /// # Failure
127    ///
128    /// Will return `Err` if no row is inserted or many rows are inserted.
129    #[inline]
130    pub fn insert<P: Params>(&mut self, params: P) -> Result<i64> {
131        let changes = self.execute(params)?;
132        match changes {
133            1 => Ok(self.conn.last_insert_rowid()),
134            _ => Err(Error::StatementChangedRows(changes)),
135        }
136    }
137
138    /// Execute the prepared statement, returning a handle to the resulting
139    /// rows.
140    ///
141    /// Due to lifetime restrictions, the rows handle returned by `query` does
142    /// not implement the `Iterator` trait. Consider using
143    /// [`query_map`](Statement::query_map) or
144    /// [`query_and_then`](Statement::query_and_then) instead, which do.
145    ///
146    /// ## Example
147    ///
148    /// ### Use without parameters
149    ///
150    /// ```rust,no_run
151    /// # use rusqlite::{Connection, Result};
152    /// fn get_names(conn: &Connection) -> Result<Vec<String>> {
153    ///     let mut stmt = conn.prepare("SELECT name FROM people")?;
154    ///     let mut rows = stmt.query([])?;
155    ///
156    ///     let mut names = Vec::new();
157    ///     while let Some(row) = rows.next()? {
158    ///         names.push(row.get(0)?);
159    ///     }
160    ///
161    ///     Ok(names)
162    /// }
163    /// ```
164    ///
165    /// ### Use with positional parameters
166    ///
167    /// ```rust,no_run
168    /// # use rusqlite::{Connection, Result};
169    /// fn query(conn: &Connection, name: &str) -> Result<()> {
170    ///     let mut stmt = conn.prepare("SELECT * FROM test where name = ?1")?;
171    ///     let mut rows = stmt.query(rusqlite::params![name])?;
172    ///     while let Some(row) = rows.next()? {
173    ///         // ...
174    ///     }
175    ///     Ok(())
176    /// }
177    /// ```
178    ///
179    /// Or, equivalently (but without the [`crate::params!`] macro).
180    ///
181    /// ```rust,no_run
182    /// # use rusqlite::{Connection, Result};
183    /// fn query(conn: &Connection, name: &str) -> Result<()> {
184    ///     let mut stmt = conn.prepare("SELECT * FROM test where name = ?1")?;
185    ///     let mut rows = stmt.query([name])?;
186    ///     while let Some(row) = rows.next()? {
187    ///         // ...
188    ///     }
189    ///     Ok(())
190    /// }
191    /// ```
192    ///
193    /// ### Use with named parameters
194    ///
195    /// ```rust,no_run
196    /// # use rusqlite::{Connection, Result};
197    /// fn query(conn: &Connection) -> Result<()> {
198    ///     let mut stmt = conn.prepare("SELECT * FROM test where name = :name")?;
199    ///     let mut rows = stmt.query(&[(":name", "one")])?;
200    ///     while let Some(row) = rows.next()? {
201    ///         // ...
202    ///     }
203    ///     Ok(())
204    /// }
205    /// ```
206    ///
207    /// Note, the `named_params!` macro is provided for syntactic convenience,
208    /// and so the above example could also be written as:
209    ///
210    /// ```rust,no_run
211    /// # use rusqlite::{Connection, Result, named_params};
212    /// fn query(conn: &Connection) -> Result<()> {
213    ///     let mut stmt = conn.prepare("SELECT * FROM test where name = :name")?;
214    ///     let mut rows = stmt.query(named_params! { ":name": "one" })?;
215    ///     while let Some(row) = rows.next()? {
216    ///         // ...
217    ///     }
218    ///     Ok(())
219    /// }
220    /// ```
221    ///
222    /// ## Failure
223    ///
224    /// Will return `Err` if binding parameters fails.
225    #[inline]
226    pub fn query<P: Params>(&mut self, params: P) -> Result<Rows<'_>> {
227        params.__bind_in(self)?;
228        Ok(Rows::new(self))
229    }
230
231    /// Executes the prepared statement and maps a function over the resulting
232    /// rows, returning an iterator over the mapped function results.
233    ///
234    /// `f` is used to transform the _streaming_ iterator into a _standard_
235    /// iterator.
236    ///
237    /// This is equivalent to `stmt.query(params)?.mapped(f)`.
238    ///
239    /// ## Example
240    ///
241    /// ### Use with positional params
242    ///
243    /// ```rust,no_run
244    /// # use rusqlite::{Connection, Result};
245    /// fn get_names(conn: &Connection) -> Result<Vec<String>> {
246    ///     let mut stmt = conn.prepare("SELECT name FROM people")?;
247    ///     let rows = stmt.query_map([], |row| row.get(0))?;
248    ///
249    ///     let mut names = Vec::new();
250    ///     for name_result in rows {
251    ///         names.push(name_result?);
252    ///     }
253    ///
254    ///     Ok(names)
255    /// }
256    /// ```
257    ///
258    /// ### Use with named params
259    ///
260    /// ```rust,no_run
261    /// # use rusqlite::{Connection, Result};
262    /// fn get_names(conn: &Connection) -> Result<Vec<String>> {
263    ///     let mut stmt = conn.prepare("SELECT name FROM people WHERE id = :id")?;
264    ///     let rows = stmt.query_map(&[(":id", &"one")], |row| row.get(0))?;
265    ///
266    ///     let mut names = Vec::new();
267    ///     for name_result in rows {
268    ///         names.push(name_result?);
269    ///     }
270    ///
271    ///     Ok(names)
272    /// }
273    /// ```
274    /// ## Failure
275    ///
276    /// Will return `Err` if binding parameters fails.
277    pub fn query_map<T, P, F>(&mut self, params: P, f: F) -> Result<MappedRows<'_, F>>
278    where
279        P: Params,
280        F: FnMut(&Row<'_>) -> Result<T>,
281    {
282        self.query(params).map(|rows| rows.mapped(f))
283    }
284
285    /// Executes the prepared statement and maps a function over the resulting
286    /// rows, where the function returns a `Result` with `Error` type
287    /// implementing `std::convert::From<Error>` (so errors can be unified).
288    ///
289    /// This is equivalent to `stmt.query(params)?.and_then(f)`.
290    ///
291    /// ## Example
292    ///
293    /// ### Use with named params
294    ///
295    /// ```rust,no_run
296    /// # use rusqlite::{Connection, Result};
297    /// struct Person {
298    ///     name: String,
299    /// };
300    ///
301    /// fn name_to_person(name: String) -> Result<Person> {
302    ///     // ... check for valid name
303    ///     Ok(Person { name })
304    /// }
305    ///
306    /// fn get_names(conn: &Connection) -> Result<Vec<Person>> {
307    ///     let mut stmt = conn.prepare("SELECT name FROM people WHERE id = :id")?;
308    ///     let rows = stmt.query_and_then(&[(":id", "one")], |row| name_to_person(row.get(0)?))?;
309    ///
310    ///     let mut persons = Vec::new();
311    ///     for person_result in rows {
312    ///         persons.push(person_result?);
313    ///     }
314    ///
315    ///     Ok(persons)
316    /// }
317    /// ```
318    ///
319    /// ### Use with positional params
320    ///
321    /// ```rust,no_run
322    /// # use rusqlite::{Connection, Result};
323    /// fn get_names(conn: &Connection) -> Result<Vec<String>> {
324    ///     let mut stmt = conn.prepare("SELECT name FROM people WHERE id = ?1")?;
325    ///     let rows = stmt.query_and_then(["one"], |row| row.get::<_, String>(0))?;
326    ///
327    ///     let mut persons = Vec::new();
328    ///     for person_result in rows {
329    ///         persons.push(person_result?);
330    ///     }
331    ///
332    ///     Ok(persons)
333    /// }
334    /// ```
335    ///
336    /// # Failure
337    ///
338    /// Will return `Err` if binding parameters fails.
339    #[inline]
340    pub fn query_and_then<T, E, P, F>(&mut self, params: P, f: F) -> Result<AndThenRows<'_, F>>
341    where
342        P: Params,
343        E: From<Error>,
344        F: FnMut(&Row<'_>) -> Result<T, E>,
345    {
346        self.query(params).map(|rows| rows.and_then(f))
347    }
348
349    /// Return `true` if a query in the SQL statement it executes returns one
350    /// or more rows and `false` if the SQL returns an empty set.
351    #[inline]
352    pub fn exists<P: Params>(&mut self, params: P) -> Result<bool> {
353        let mut rows = self.query(params)?;
354        let exists = rows.next()?.is_some();
355        Ok(exists)
356    }
357
358    /// Convenience method to execute a query that is expected to return a
359    /// single row.
360    ///
361    /// If the query returns more than one row, all rows except the first are
362    /// ignored.
363    ///
364    /// Returns `Err(QueryReturnedNoRows)` if no results are returned. If the
365    /// query truly is optional, you can call
366    /// [`.optional()`](crate::OptionalExtension::optional) on the result of
367    /// this to get a `Result<Option<T>>` (requires that the trait
368    /// `rusqlite::OptionalExtension` is imported).
369    ///
370    /// # Failure
371    ///
372    /// Will return `Err` if the underlying SQLite call fails.
373    pub fn query_row<T, P, F>(&mut self, params: P, f: F) -> Result<T>
374    where
375        P: Params,
376        F: FnOnce(&Row<'_>) -> Result<T>,
377    {
378        let mut rows = self.query(params)?;
379
380        rows.get_expected_row().and_then(f)
381    }
382
383    /// Consumes the statement.
384    ///
385    /// Functionally equivalent to the `Drop` implementation, but allows
386    /// callers to see any errors that occur.
387    ///
388    /// # Failure
389    ///
390    /// Will return `Err` if the underlying SQLite call fails.
391    #[inline]
392    pub fn finalize(mut self) -> Result<()> {
393        self.finalize_()
394    }
395
396    /// Return the (one-based) index of an SQL parameter given its name.
397    ///
398    /// Note that the initial ":" or "$" or "@" or "?" used to specify the
399    /// parameter is included as part of the name.
400    ///
401    /// ```rust,no_run
402    /// # use rusqlite::{Connection, Result};
403    /// fn example(conn: &Connection) -> Result<()> {
404    ///     let stmt = conn.prepare("SELECT * FROM test WHERE name = :example")?;
405    ///     let index = stmt.parameter_index(":example")?;
406    ///     assert_eq!(index, Some(1));
407    ///     Ok(())
408    /// }
409    /// ```
410    ///
411    /// # Failure
412    ///
413    /// Will return Err if `name` is invalid. Will return Ok(None) if the name
414    /// is valid but not a bound parameter of this statement.
415    #[inline]
416    pub fn parameter_index(&self, name: &str) -> Result<Option<usize>> {
417        Ok(self.stmt.bind_parameter_index(name))
418    }
419
420    /// Return the SQL parameter name given its (one-based) index (the inverse
421    /// of [`Statement::parameter_index`]).
422    ///
423    /// ```rust,no_run
424    /// # use rusqlite::{Connection, Result};
425    /// fn example(conn: &Connection) -> Result<()> {
426    ///     let stmt = conn.prepare("SELECT * FROM test WHERE name = :example")?;
427    ///     let index = stmt.parameter_name(1);
428    ///     assert_eq!(index, Some(":example"));
429    ///     Ok(())
430    /// }
431    /// ```
432    ///
433    /// # Failure
434    ///
435    /// Will return `None` if the column index is out of bounds or if the
436    /// parameter is positional.
437    ///
438    /// # Panics
439    ///
440    /// Panics when parameter name is not valid UTF-8.
441    #[inline]
442    pub fn parameter_name(&self, index: usize) -> Option<&'_ str> {
443        self.stmt.bind_parameter_name(index as i32).map(|name| {
444            name.to_str()
445                .expect("Invalid UTF-8 sequence in parameter name")
446        })
447    }
448
449    #[inline]
450    pub(crate) fn bind_parameters<P>(&mut self, params: P) -> Result<()>
451    where
452        P: IntoIterator,
453        P::Item: ToSql,
454    {
455        let expected = self.stmt.bind_parameter_count();
456        let mut index = 0;
457        for p in params {
458            index += 1; // The leftmost SQL parameter has an index of 1.
459            if index > expected {
460                break;
461            }
462            self.bind_parameter(&p, index)?;
463        }
464        if index != expected {
465            Err(Error::InvalidParameterCount(index, expected))
466        } else {
467            Ok(())
468        }
469    }
470
471    #[inline]
472    pub(crate) fn ensure_parameter_count(&self, n: usize) -> Result<()> {
473        let count = self.parameter_count();
474        if count != n {
475            Err(Error::InvalidParameterCount(n, count))
476        } else {
477            Ok(())
478        }
479    }
480
481    #[inline]
482    pub(crate) fn bind_parameters_named<T: ?Sized + ToSql>(
483        &mut self,
484        params: &[(&str, &T)],
485    ) -> Result<()> {
486        for &(name, value) in params {
487            if let Some(i) = self.parameter_index(name)? {
488                let ts: &dyn ToSql = &value;
489                self.bind_parameter(ts, i)?;
490            } else {
491                return Err(Error::InvalidParameterName(name.into()));
492            }
493        }
494        Ok(())
495    }
496
497    /// Return the number of parameters that can be bound to this statement.
498    #[inline]
499    pub fn parameter_count(&self) -> usize {
500        self.stmt.bind_parameter_count()
501    }
502
503    /// Low level API to directly bind a parameter to a given index.
504    ///
505    /// Note that the index is one-based, that is, the first parameter index is
506    /// 1 and not 0. This is consistent with the SQLite API and the values given
507    /// to parameters bound as `?NNN`.
508    ///
509    /// The valid values for `one_based_col_index` begin at `1`, and end at
510    /// [`Statement::parameter_count`], inclusive.
511    ///
512    /// # Caveats
513    ///
514    /// This should not generally be used, but is available for special cases
515    /// such as:
516    ///
517    /// - binding parameters where a gap exists.
518    /// - binding named and positional parameters in the same query.
519    /// - separating parameter binding from query execution.
520    ///
521    /// In general, statements that have had *any* parameters bound this way
522    /// should have *all* parameters bound this way, and be queried or executed
523    /// by [`Statement::raw_query`] or [`Statement::raw_execute`], other usage
524    /// is unsupported and will likely, probably in surprising ways.
525    ///
526    /// That is: Do not mix the "raw" statement functions with the rest of the
527    /// API, or the results may be surprising, and may even change in future
528    /// versions without comment.
529    ///
530    /// # Example
531    ///
532    /// ```rust,no_run
533    /// # use rusqlite::{Connection, Result};
534    /// fn query(conn: &Connection) -> Result<()> {
535    ///     let mut stmt = conn.prepare("SELECT * FROM test WHERE name = :name AND value > ?2")?;
536    ///     let name_index = stmt.parameter_index(":name")?.expect("No such parameter");
537    ///     stmt.raw_bind_parameter(name_index, "foo")?;
538    ///     stmt.raw_bind_parameter(2, 100)?;
539    ///     let mut rows = stmt.raw_query();
540    ///     while let Some(row) = rows.next()? {
541    ///         // ...
542    ///     }
543    ///     Ok(())
544    /// }
545    /// ```
546    #[inline]
547    pub fn raw_bind_parameter<T: ToSql>(
548        &mut self,
549        one_based_col_index: usize,
550        param: T,
551    ) -> Result<()> {
552        // This is the same as `bind_parameter` but slightly more ergonomic and
553        // correctly takes `&mut self`.
554        self.bind_parameter(&param, one_based_col_index)
555    }
556
557    /// Low level API to execute a statement given that all parameters were
558    /// bound explicitly with the [`Statement::raw_bind_parameter`] API.
559    ///
560    /// # Caveats
561    ///
562    /// Any unbound parameters will have `NULL` as their value.
563    ///
564    /// This should not generally be used outside special cases, and
565    /// functions in the [`Statement::execute`] family should be preferred.
566    ///
567    /// # Failure
568    ///
569    /// Will return `Err` if the executed statement returns rows (in which case
570    /// `query` should be used instead), or the underlying SQLite call fails.
571    #[inline]
572    pub fn raw_execute(&mut self) -> Result<usize> {
573        self.execute_with_bound_parameters()
574    }
575
576    /// Low level API to get `Rows` for this query given that all parameters
577    /// were bound explicitly with the [`Statement::raw_bind_parameter`] API.
578    ///
579    /// # Caveats
580    ///
581    /// Any unbound parameters will have `NULL` as their value.
582    ///
583    /// This should not generally be used outside special cases, and
584    /// functions in the [`Statement::query`] family should be preferred.
585    ///
586    /// Note that if the SQL does not return results, [`Statement::raw_execute`]
587    /// should be used instead.
588    #[inline]
589    pub fn raw_query(&mut self) -> Rows<'_> {
590        Rows::new(self)
591    }
592
593    // generic because many of these branches can constant fold away.
594    fn bind_parameter<P: ?Sized + ToSql>(&self, param: &P, col: usize) -> Result<()> {
595        let value = param.to_sql()?;
596
597        let ptr = unsafe { self.stmt.ptr() };
598        let value = match value {
599            ToSqlOutput::Borrowed(v) => v,
600            ToSqlOutput::Owned(ref v) => ValueRef::from(v),
601
602            #[cfg(feature = "blob")]
603            ToSqlOutput::ZeroBlob(len) => {
604                // TODO sqlite3_bind_zeroblob64 // 3.8.11
605                return self
606                    .conn
607                    .decode_result(unsafe { ffi::sqlite3_bind_zeroblob(ptr, col as c_int, len) });
608            }
609            #[cfg(feature = "functions")]
610            ToSqlOutput::Arg(_) => {
611                return Err(err!(ffi::SQLITE_MISUSE, "Unsupported value \"{value:?}\""));
612            }
613            #[cfg(feature = "array")]
614            ToSqlOutput::Array(a) => {
615                return self.conn.decode_result(unsafe {
616                    ffi::sqlite3_bind_pointer(
617                        ptr,
618                        col as c_int,
619                        Rc::into_raw(a) as *mut c_void,
620                        ARRAY_TYPE,
621                        Some(free_array),
622                    )
623                });
624            }
625        };
626        self.conn.decode_result(match value {
627            ValueRef::Null => unsafe { ffi::sqlite3_bind_null(ptr, col as c_int) },
628            ValueRef::Integer(i) => unsafe { ffi::sqlite3_bind_int64(ptr, col as c_int, i) },
629            ValueRef::Real(r) => unsafe { ffi::sqlite3_bind_double(ptr, col as c_int, r) },
630            ValueRef::Text(s) => unsafe {
631                let (c_str, len, destructor) = str_for_sqlite(s)?;
632                // TODO sqlite3_bind_text64 // 3.8.7
633                ffi::sqlite3_bind_text(ptr, col as c_int, c_str, len, destructor)
634            },
635            ValueRef::Blob(b) => unsafe {
636                let length = len_as_c_int(b.len())?;
637                if length == 0 {
638                    ffi::sqlite3_bind_zeroblob(ptr, col as c_int, 0)
639                } else {
640                    // TODO sqlite3_bind_blob64 // 3.8.7
641                    ffi::sqlite3_bind_blob(
642                        ptr,
643                        col as c_int,
644                        b.as_ptr().cast::<c_void>(),
645                        length,
646                        ffi::SQLITE_TRANSIENT(),
647                    )
648                }
649            },
650        })
651    }
652
653    #[inline]
654    fn execute_with_bound_parameters(&mut self) -> Result<usize> {
655        self.check_update()?;
656        let r = self.stmt.step();
657        let rr = self.stmt.reset();
658        match r {
659            ffi::SQLITE_DONE => match rr {
660                ffi::SQLITE_OK => Ok(self.conn.changes() as usize),
661                _ => Err(self.conn.decode_result(rr).unwrap_err()),
662            },
663            ffi::SQLITE_ROW => Err(Error::ExecuteReturnedResults),
664            _ => Err(self.conn.decode_result(r).unwrap_err()),
665        }
666    }
667
668    #[inline]
669    fn finalize_(&mut self) -> Result<()> {
670        let mut stmt = unsafe { RawStatement::new(ptr::null_mut(), 0) };
671        mem::swap(&mut stmt, &mut self.stmt);
672        self.conn.decode_result(stmt.finalize())
673    }
674
675    #[cfg(feature = "extra_check")]
676    #[inline]
677    fn check_update(&self) -> Result<()> {
678        // sqlite3_column_count works for DML but not for DDL (ie ALTER)
679        if self.column_count() > 0 && self.stmt.readonly() {
680            return Err(Error::ExecuteReturnedResults);
681        }
682        Ok(())
683    }
684
685    #[cfg(not(feature = "extra_check"))]
686    #[inline]
687    #[expect(clippy::unnecessary_wraps)]
688    fn check_update(&self) -> Result<()> {
689        Ok(())
690    }
691
692    /// Returns a string containing the SQL text of prepared statement with
693    /// bound parameters expanded.
694    pub fn expanded_sql(&self) -> Option<String> {
695        self.stmt
696            .expanded_sql()
697            .map(|s| s.to_string_lossy().to_string())
698    }
699
700    /// Get the value for one of the status counters for this statement.
701    #[inline]
702    pub fn get_status(&self, status: StatementStatus) -> i32 {
703        self.stmt.get_status(status, false)
704    }
705
706    /// Reset the value of one of the status counters for this statement,
707    #[inline]
708    /// returning the value it had before resetting.
709    pub fn reset_status(&self, status: StatementStatus) -> i32 {
710        self.stmt.get_status(status, true)
711    }
712
713    /// Returns 1 if the prepared statement is an EXPLAIN statement,
714    /// or 2 if the statement is an EXPLAIN QUERY PLAN,
715    /// or 0 if it is an ordinary statement or a NULL pointer.
716    #[inline]
717    #[cfg(feature = "modern_sqlite")] // 3.28.0
718    #[cfg_attr(docsrs, doc(cfg(feature = "modern_sqlite")))]
719    pub fn is_explain(&self) -> i32 {
720        self.stmt.is_explain()
721    }
722
723    /// Returns true if the statement is read only.
724    #[inline]
725    pub fn readonly(&self) -> bool {
726        self.stmt.readonly()
727    }
728
729    #[cfg(feature = "extra_check")]
730    #[inline]
731    pub(crate) fn check_no_tail(&self) -> Result<()> {
732        if self.stmt.has_tail() {
733            Err(Error::MultipleStatement)
734        } else {
735            Ok(())
736        }
737    }
738
739    #[cfg(not(feature = "extra_check"))]
740    #[inline]
741    #[expect(clippy::unnecessary_wraps)]
742    pub(crate) fn check_no_tail(&self) -> Result<()> {
743        Ok(())
744    }
745
746    /// Safety: This is unsafe, because using `sqlite3_stmt` after the
747    /// connection has closed is illegal, but `RawStatement` does not enforce
748    /// this, as it loses our protective `'conn` lifetime bound.
749    #[inline]
750    pub(crate) unsafe fn into_raw(mut self) -> RawStatement {
751        let mut stmt = RawStatement::new(ptr::null_mut(), 0);
752        mem::swap(&mut stmt, &mut self.stmt);
753        stmt
754    }
755
756    /// Reset all bindings
757    pub fn clear_bindings(&mut self) {
758        self.stmt.clear_bindings();
759    }
760}
761
762impl fmt::Debug for Statement<'_> {
763    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
764        let sql = if self.stmt.is_null() {
765            Ok("")
766        } else {
767            self.stmt.sql().unwrap().to_str()
768        };
769        f.debug_struct("Statement")
770            .field("conn", self.conn)
771            .field("stmt", &self.stmt)
772            .field("sql", &sql)
773            .finish()
774    }
775}
776
777impl Drop for Statement<'_> {
778    #[expect(unused_must_use)]
779    #[inline]
780    fn drop(&mut self) {
781        self.finalize_();
782    }
783}
784
785impl Statement<'_> {
786    #[inline]
787    pub(super) fn new(conn: &Connection, stmt: RawStatement) -> Statement<'_> {
788        Statement { conn, stmt }
789    }
790
791    pub(super) fn value_ref(&self, col: usize) -> ValueRef<'_> {
792        let raw = unsafe { self.stmt.ptr() };
793
794        match self.stmt.column_type(col) {
795            ffi::SQLITE_NULL => ValueRef::Null,
796            ffi::SQLITE_INTEGER => {
797                ValueRef::Integer(unsafe { ffi::sqlite3_column_int64(raw, col as c_int) })
798            }
799            ffi::SQLITE_FLOAT => {
800                ValueRef::Real(unsafe { ffi::sqlite3_column_double(raw, col as c_int) })
801            }
802            ffi::SQLITE_TEXT => {
803                let s = unsafe {
804                    // Quoting from "Using SQLite" book:
805                    // To avoid problems, an application should first extract the desired type using
806                    // a sqlite3_column_xxx() function, and then call the
807                    // appropriate sqlite3_column_bytes() function.
808                    let text = ffi::sqlite3_column_text(raw, col as c_int);
809                    let len = ffi::sqlite3_column_bytes(raw, col as c_int);
810                    assert!(
811                        !text.is_null(),
812                        "unexpected SQLITE_TEXT column type with NULL data"
813                    );
814                    from_raw_parts(text.cast::<u8>(), len as usize)
815                };
816
817                ValueRef::Text(s)
818            }
819            ffi::SQLITE_BLOB => {
820                let (blob, len) = unsafe {
821                    (
822                        ffi::sqlite3_column_blob(raw, col as c_int),
823                        ffi::sqlite3_column_bytes(raw, col as c_int),
824                    )
825                };
826
827                assert!(
828                    len >= 0,
829                    "unexpected negative return from sqlite3_column_bytes"
830                );
831                if len > 0 {
832                    assert!(
833                        !blob.is_null(),
834                        "unexpected SQLITE_BLOB column type with NULL data"
835                    );
836                    ValueRef::Blob(unsafe { from_raw_parts(blob.cast::<u8>(), len as usize) })
837                } else {
838                    // The return value from sqlite3_column_blob() for a zero-length BLOB
839                    // is a NULL pointer.
840                    ValueRef::Blob(&[])
841                }
842            }
843            _ => unreachable!("sqlite3_column_type returned invalid value"),
844        }
845    }
846
847    #[inline]
848    pub(super) fn step(&self) -> Result<bool> {
849        match self.stmt.step() {
850            ffi::SQLITE_ROW => Ok(true),
851            ffi::SQLITE_DONE => Ok(false),
852            code => Err(self.conn.decode_result(code).unwrap_err()),
853        }
854    }
855
856    #[inline]
857    pub(super) fn reset(&self) -> Result<()> {
858        match self.stmt.reset() {
859            ffi::SQLITE_OK => Ok(()),
860            code => Err(self.conn.decode_result(code).unwrap_err()),
861        }
862    }
863}
864
865/// Prepared statement status counters.
866///
867/// See `https://www.sqlite.org/c3ref/c_stmtstatus_counter.html`
868/// for explanations of each.
869///
870/// Note that depending on your version of SQLite, all of these
871/// may not be available.
872#[repr(i32)]
873#[derive(Clone, Copy, PartialEq, Eq)]
874#[non_exhaustive]
875pub enum StatementStatus {
876    /// Equivalent to `SQLITE_STMTSTATUS_FULLSCAN_STEP`
877    FullscanStep = 1,
878    /// Equivalent to `SQLITE_STMTSTATUS_SORT`
879    Sort = 2,
880    /// Equivalent to `SQLITE_STMTSTATUS_AUTOINDEX`
881    AutoIndex = 3,
882    /// Equivalent to `SQLITE_STMTSTATUS_VM_STEP`
883    VmStep = 4,
884    /// Equivalent to `SQLITE_STMTSTATUS_REPREPARE` (3.20.0)
885    RePrepare = 5,
886    /// Equivalent to `SQLITE_STMTSTATUS_RUN` (3.20.0)
887    Run = 6,
888    /// Equivalent to `SQLITE_STMTSTATUS_FILTER_MISS`
889    FilterMiss = 7,
890    /// Equivalent to `SQLITE_STMTSTATUS_FILTER_HIT`
891    FilterHit = 8,
892    /// Equivalent to `SQLITE_STMTSTATUS_MEMUSED` (3.20.0)
893    MemUsed = 99,
894}
895
896#[cfg(test)]
897mod test {
898    use crate::types::ToSql;
899    use crate::{params_from_iter, Connection, Error, Result};
900
901    #[test]
902    fn test_execute_named() -> Result<()> {
903        let db = Connection::open_in_memory()?;
904        db.execute_batch("CREATE TABLE foo(x INTEGER)")?;
905
906        assert_eq!(
907            db.execute("INSERT INTO foo(x) VALUES (:x)", &[(":x", &1i32)])?,
908            1
909        );
910        assert_eq!(
911            db.execute("INSERT INTO foo(x) VALUES (:x)", &[(":x", &2i32)])?,
912            1
913        );
914        assert_eq!(
915            db.execute(
916                "INSERT INTO foo(x) VALUES (:x)",
917                crate::named_params! {":x": 3i32}
918            )?,
919            1
920        );
921
922        assert_eq!(
923            6i32,
924            db.query_row::<i32, _, _>(
925                "SELECT SUM(x) FROM foo WHERE x > :x",
926                &[(":x", &0i32)],
927                |r| r.get(0)
928            )?
929        );
930        assert_eq!(
931            5i32,
932            db.query_row::<i32, _, _>(
933                "SELECT SUM(x) FROM foo WHERE x > :x",
934                &[(":x", &1i32)],
935                |r| r.get(0)
936            )?
937        );
938        Ok(())
939    }
940
941    #[test]
942    fn test_stmt_execute_named() -> Result<()> {
943        let db = Connection::open_in_memory()?;
944        let sql = "CREATE TABLE test (id INTEGER PRIMARY KEY NOT NULL, name TEXT NOT NULL, flag \
945                   INTEGER)";
946        db.execute_batch(sql)?;
947
948        let mut stmt = db.prepare("INSERT INTO test (name) VALUES (:name)")?;
949        stmt.execute(&[(":name", &"one")])?;
950
951        let mut stmt = db.prepare("SELECT COUNT(*) FROM test WHERE name = :name")?;
952        assert_eq!(
953            1i32,
954            stmt.query_row::<i32, _, _>(&[(":name", "one")], |r| r.get(0))?
955        );
956        Ok(())
957    }
958
959    #[test]
960    fn test_query_named() -> Result<()> {
961        let db = Connection::open_in_memory()?;
962        let sql = r#"
963        CREATE TABLE test (id INTEGER PRIMARY KEY NOT NULL, name TEXT NOT NULL, flag INTEGER);
964        INSERT INTO test(id, name) VALUES (1, "one");
965        "#;
966        db.execute_batch(sql)?;
967
968        let mut stmt = db.prepare("SELECT id FROM test where name = :name")?;
969        let mut rows = stmt.query(&[(":name", "one")])?;
970        let id: Result<i32> = rows.next()?.unwrap().get(0);
971        assert_eq!(Ok(1), id);
972        Ok(())
973    }
974
975    #[test]
976    fn test_query_map_named() -> Result<()> {
977        let db = Connection::open_in_memory()?;
978        let sql = r#"
979        CREATE TABLE test (id INTEGER PRIMARY KEY NOT NULL, name TEXT NOT NULL, flag INTEGER);
980        INSERT INTO test(id, name) VALUES (1, "one");
981        "#;
982        db.execute_batch(sql)?;
983
984        let mut stmt = db.prepare("SELECT id FROM test where name = :name")?;
985        let mut rows = stmt.query_map(&[(":name", "one")], |row| {
986            let id: Result<i32> = row.get(0);
987            id.map(|i| 2 * i)
988        })?;
989
990        let doubled_id: i32 = rows.next().unwrap()?;
991        assert_eq!(2, doubled_id);
992        Ok(())
993    }
994
995    #[test]
996    fn test_query_and_then_by_name() -> Result<()> {
997        let db = Connection::open_in_memory()?;
998        let sql = r#"
999        CREATE TABLE test (id INTEGER PRIMARY KEY NOT NULL, name TEXT NOT NULL, flag INTEGER);
1000        INSERT INTO test(id, name) VALUES (1, "one");
1001        INSERT INTO test(id, name) VALUES (2, "one");
1002        "#;
1003        db.execute_batch(sql)?;
1004
1005        let mut stmt = db.prepare("SELECT id FROM test where name = :name ORDER BY id ASC")?;
1006        let mut rows = stmt.query_and_then(&[(":name", "one")], |row| {
1007            let id: i32 = row.get(0)?;
1008            if id == 1 {
1009                Ok(id)
1010            } else {
1011                Err(Error::SqliteSingleThreadedMode)
1012            }
1013        })?;
1014
1015        // first row should be Ok
1016        let doubled_id: i32 = rows.next().unwrap()?;
1017        assert_eq!(1, doubled_id);
1018
1019        // second row should be an `Err`
1020        #[expect(clippy::match_wild_err_arm)]
1021        match rows.next().unwrap() {
1022            Ok(_) => panic!("invalid Ok"),
1023            Err(Error::SqliteSingleThreadedMode) => (),
1024            Err(_) => panic!("invalid Err"),
1025        }
1026        Ok(())
1027    }
1028
1029    #[test]
1030    fn test_unbound_parameters_are_null() -> Result<()> {
1031        let db = Connection::open_in_memory()?;
1032        let sql = "CREATE TABLE test (x TEXT, y TEXT)";
1033        db.execute_batch(sql)?;
1034
1035        let mut stmt = db.prepare("INSERT INTO test (x, y) VALUES (:x, :y)")?;
1036        stmt.execute(&[(":x", &"one")])?;
1037
1038        let result: Option<String> = db.one_column("SELECT y FROM test WHERE x = 'one'")?;
1039        assert!(result.is_none());
1040        Ok(())
1041    }
1042
1043    #[test]
1044    fn test_raw_binding() -> Result<()> {
1045        let db = Connection::open_in_memory()?;
1046        db.execute_batch("CREATE TABLE test (name TEXT, value INTEGER)")?;
1047        {
1048            let mut stmt = db.prepare("INSERT INTO test (name, value) VALUES (:name, ?3)")?;
1049
1050            let name_idx = stmt.parameter_index(":name")?.unwrap();
1051            stmt.raw_bind_parameter(name_idx, "example")?;
1052            stmt.raw_bind_parameter(3, 50i32)?;
1053            let n = stmt.raw_execute()?;
1054            assert_eq!(n, 1);
1055        }
1056
1057        {
1058            let mut stmt = db.prepare("SELECT name, value FROM test WHERE value = ?2")?;
1059            stmt.raw_bind_parameter(2, 50)?;
1060            let mut rows = stmt.raw_query();
1061            {
1062                let row = rows.next()?.unwrap();
1063                let name: String = row.get(0)?;
1064                assert_eq!(name, "example");
1065                let value: i32 = row.get(1)?;
1066                assert_eq!(value, 50);
1067            }
1068            assert!(rows.next()?.is_none());
1069        }
1070
1071        Ok(())
1072    }
1073
1074    #[test]
1075    fn test_unbound_parameters_are_reused() -> Result<()> {
1076        let db = Connection::open_in_memory()?;
1077        let sql = "CREATE TABLE test (x TEXT, y TEXT)";
1078        db.execute_batch(sql)?;
1079
1080        let mut stmt = db.prepare("INSERT INTO test (x, y) VALUES (:x, :y)")?;
1081        stmt.execute(&[(":x", "one")])?;
1082        stmt.execute(&[(":y", "two")])?;
1083
1084        let result: String = db.one_column("SELECT x FROM test WHERE y = 'two'")?;
1085        assert_eq!(result, "one");
1086        Ok(())
1087    }
1088
1089    #[test]
1090    fn test_insert() -> Result<()> {
1091        let db = Connection::open_in_memory()?;
1092        db.execute_batch("CREATE TABLE foo(x INTEGER UNIQUE)")?;
1093        let mut stmt = db.prepare("INSERT OR IGNORE INTO foo (x) VALUES (?1)")?;
1094        assert_eq!(stmt.insert([1i32])?, 1);
1095        assert_eq!(stmt.insert([2i32])?, 2);
1096        match stmt.insert([1i32]).unwrap_err() {
1097            Error::StatementChangedRows(0) => (),
1098            err => panic!("Unexpected error {err}"),
1099        }
1100        let mut multi = db.prepare("INSERT INTO foo (x) SELECT 3 UNION ALL SELECT 4")?;
1101        match multi.insert([]).unwrap_err() {
1102            Error::StatementChangedRows(2) => (),
1103            err => panic!("Unexpected error {err}"),
1104        }
1105        Ok(())
1106    }
1107
1108    #[test]
1109    fn test_insert_different_tables() -> Result<()> {
1110        // Test for https://github.com/rusqlite/rusqlite/issues/171
1111        let db = Connection::open_in_memory()?;
1112        db.execute_batch(
1113            r"
1114            CREATE TABLE foo(x INTEGER);
1115            CREATE TABLE bar(x INTEGER);
1116        ",
1117        )?;
1118
1119        assert_eq!(db.prepare("INSERT INTO foo VALUES (10)")?.insert([])?, 1);
1120        assert_eq!(db.prepare("INSERT INTO bar VALUES (10)")?.insert([])?, 1);
1121        Ok(())
1122    }
1123
1124    #[test]
1125    fn test_exists() -> Result<()> {
1126        let db = Connection::open_in_memory()?;
1127        let sql = "BEGIN;
1128                   CREATE TABLE foo(x INTEGER);
1129                   INSERT INTO foo VALUES(1);
1130                   INSERT INTO foo VALUES(2);
1131                   END;";
1132        db.execute_batch(sql)?;
1133        let mut stmt = db.prepare("SELECT 1 FROM foo WHERE x = ?1")?;
1134        assert!(stmt.exists([1i32])?);
1135        assert!(stmt.exists([2i32])?);
1136        assert!(!stmt.exists([0i32])?);
1137        Ok(())
1138    }
1139    #[test]
1140    fn test_tuple_params() -> Result<()> {
1141        let db = Connection::open_in_memory()?;
1142        let s = db.query_row("SELECT printf('[%s]', ?1)", ("abc",), |r| {
1143            r.get::<_, String>(0)
1144        })?;
1145        assert_eq!(s, "[abc]");
1146        let s = db.query_row(
1147            "SELECT printf('%d %s %d', ?1, ?2, ?3)",
1148            (1i32, "abc", 2i32),
1149            |r| r.get::<_, String>(0),
1150        )?;
1151        assert_eq!(s, "1 abc 2");
1152        let s = db.query_row(
1153            "SELECT printf('%d %s %d %d', ?1, ?2, ?3, ?4)",
1154            (1, "abc", 2i32, 4i64),
1155            |r| r.get::<_, String>(0),
1156        )?;
1157        assert_eq!(s, "1 abc 2 4");
1158        #[rustfmt::skip]
1159        let bigtup = (
1160            0, "a", 1, "b", 2, "c", 3, "d",
1161            4, "e", 5, "f", 6, "g", 7, "h",
1162        );
1163        let query = "SELECT printf(
1164            '%d %s | %d %s | %d %s | %d %s || %d %s | %d %s | %d %s | %d %s',
1165            ?1, ?2, ?3, ?4,
1166            ?5, ?6, ?7, ?8,
1167            ?9, ?10, ?11, ?12,
1168            ?13, ?14, ?15, ?16
1169        )";
1170        let s = db.query_row(query, bigtup, |r| r.get::<_, String>(0))?;
1171        assert_eq!(s, "0 a | 1 b | 2 c | 3 d || 4 e | 5 f | 6 g | 7 h");
1172        Ok(())
1173    }
1174
1175    #[test]
1176    fn test_query_row() -> Result<()> {
1177        let db = Connection::open_in_memory()?;
1178        let sql = "BEGIN;
1179                   CREATE TABLE foo(x INTEGER, y INTEGER);
1180                   INSERT INTO foo VALUES(1, 3);
1181                   INSERT INTO foo VALUES(2, 4);
1182                   END;";
1183        db.execute_batch(sql)?;
1184        let mut stmt = db.prepare("SELECT y FROM foo WHERE x = ?1")?;
1185        let y: Result<i64> = stmt.query_row([1i32], |r| r.get(0));
1186        assert_eq!(3i64, y?);
1187        Ok(())
1188    }
1189
1190    #[test]
1191    fn test_query_by_column_name() -> Result<()> {
1192        let db = Connection::open_in_memory()?;
1193        let sql = "BEGIN;
1194                   CREATE TABLE foo(x INTEGER, y INTEGER);
1195                   INSERT INTO foo VALUES(1, 3);
1196                   END;";
1197        db.execute_batch(sql)?;
1198        let mut stmt = db.prepare("SELECT y FROM foo")?;
1199        let y: Result<i64> = stmt.query_row([], |r| r.get("y"));
1200        assert_eq!(3i64, y?);
1201        Ok(())
1202    }
1203
1204    #[test]
1205    fn test_query_by_column_name_ignore_case() -> Result<()> {
1206        let db = Connection::open_in_memory()?;
1207        let sql = "BEGIN;
1208                   CREATE TABLE foo(x INTEGER, y INTEGER);
1209                   INSERT INTO foo VALUES(1, 3);
1210                   END;";
1211        db.execute_batch(sql)?;
1212        let mut stmt = db.prepare("SELECT y as Y FROM foo")?;
1213        let y: Result<i64> = stmt.query_row([], |r| r.get("y"));
1214        assert_eq!(3i64, y?);
1215        Ok(())
1216    }
1217
1218    #[test]
1219    fn test_expanded_sql() -> Result<()> {
1220        let db = Connection::open_in_memory()?;
1221        let stmt = db.prepare("SELECT ?1")?;
1222        stmt.bind_parameter(&1, 1)?;
1223        assert_eq!(Some("SELECT 1".to_owned()), stmt.expanded_sql());
1224        Ok(())
1225    }
1226
1227    #[test]
1228    fn test_bind_parameters() -> Result<()> {
1229        let db = Connection::open_in_memory()?;
1230        // dynamic slice:
1231        db.query_row(
1232            "SELECT ?1, ?2, ?3",
1233            [&1u8 as &dyn ToSql, &"one", &Some("one")],
1234            |row| row.get::<_, u8>(0),
1235        )?;
1236        // existing collection:
1237        let data = vec![1, 2, 3];
1238        db.query_row("SELECT ?1, ?2, ?3", params_from_iter(&data), |row| {
1239            row.get::<_, u8>(0)
1240        })?;
1241        db.query_row(
1242            "SELECT ?1, ?2, ?3",
1243            params_from_iter(data.as_slice()),
1244            |row| row.get::<_, u8>(0),
1245        )?;
1246        db.query_row("SELECT ?1, ?2, ?3", params_from_iter(data), |row| {
1247            row.get::<_, u8>(0)
1248        })?;
1249
1250        use std::collections::BTreeSet;
1251        let data: BTreeSet<String> = ["one", "two", "three"]
1252            .iter()
1253            .map(|s| (*s).to_string())
1254            .collect();
1255        db.query_row("SELECT ?1, ?2, ?3", params_from_iter(&data), |row| {
1256            row.get::<_, String>(0)
1257        })?;
1258
1259        let data = [0; 3];
1260        db.query_row("SELECT ?1, ?2, ?3", params_from_iter(&data), |row| {
1261            row.get::<_, u8>(0)
1262        })?;
1263        db.query_row("SELECT ?1, ?2, ?3", params_from_iter(data.iter()), |row| {
1264            row.get::<_, u8>(0)
1265        })?;
1266        Ok(())
1267    }
1268
1269    #[test]
1270    fn test_parameter_name() -> Result<()> {
1271        let db = Connection::open_in_memory()?;
1272        db.execute_batch("CREATE TABLE test (name TEXT, value INTEGER)")?;
1273        let stmt = db.prepare("INSERT INTO test (name, value) VALUES (:name, ?3)")?;
1274        assert_eq!(stmt.parameter_name(0), None);
1275        assert_eq!(stmt.parameter_name(1), Some(":name"));
1276        assert_eq!(stmt.parameter_name(2), None);
1277        Ok(())
1278    }
1279
1280    #[test]
1281    fn test_empty_stmt() -> Result<()> {
1282        let conn = Connection::open_in_memory()?;
1283        let mut stmt = conn.prepare("")?;
1284        assert_eq!(0, stmt.column_count());
1285        stmt.parameter_index("test")?;
1286        let err = stmt.step().unwrap_err();
1287        assert_eq!(err.sqlite_error_code(), Some(crate::ErrorCode::ApiMisuse));
1288        // error msg is different with sqlcipher, so we use assert_ne:
1289        assert_ne!(err.to_string(), "not an error".to_owned());
1290        stmt.reset()?; // SQLITE_OMIT_AUTORESET = false
1291        stmt.execute([]).unwrap_err();
1292        Ok(())
1293    }
1294
1295    #[test]
1296    fn test_comment_stmt() -> Result<()> {
1297        let conn = Connection::open_in_memory()?;
1298        conn.prepare("/*SELECT 1;*/")?;
1299        Ok(())
1300    }
1301
1302    #[test]
1303    fn test_comment_and_sql_stmt() -> Result<()> {
1304        let conn = Connection::open_in_memory()?;
1305        let stmt = conn.prepare("/*...*/ SELECT 1;")?;
1306        assert_eq!(1, stmt.column_count());
1307        Ok(())
1308    }
1309
1310    #[test]
1311    fn test_semi_colon_stmt() -> Result<()> {
1312        let conn = Connection::open_in_memory()?;
1313        let stmt = conn.prepare(";")?;
1314        assert_eq!(0, stmt.column_count());
1315        Ok(())
1316    }
1317
1318    #[test]
1319    fn test_utf16_conversion() -> Result<()> {
1320        let db = Connection::open_in_memory()?;
1321        db.pragma_update(None, "encoding", "UTF-16le")?;
1322        let encoding: String = db.pragma_query_value(None, "encoding", |row| row.get(0))?;
1323        assert_eq!("UTF-16le", encoding);
1324        db.execute_batch("CREATE TABLE foo(x TEXT)")?;
1325        let expected = "ใƒ†ใ‚นใƒˆ";
1326        db.execute("INSERT INTO foo(x) VALUES (?1)", [&expected])?;
1327        let actual: String = db.one_column("SELECT x FROM foo")?;
1328        assert_eq!(expected, actual);
1329        Ok(())
1330    }
1331
1332    #[test]
1333    fn test_nul_byte() -> Result<()> {
1334        let db = Connection::open_in_memory()?;
1335        let expected = "a\x00b";
1336        let actual: String = db.query_row("SELECT ?1", [expected], |row| row.get(0))?;
1337        assert_eq!(expected, actual);
1338        Ok(())
1339    }
1340
1341    #[test]
1342    #[cfg(feature = "modern_sqlite")]
1343    fn is_explain() -> Result<()> {
1344        let db = Connection::open_in_memory()?;
1345        let stmt = db.prepare("SELECT 1;")?;
1346        assert_eq!(0, stmt.is_explain());
1347        Ok(())
1348    }
1349
1350    #[test]
1351    fn readonly() -> Result<()> {
1352        let db = Connection::open_in_memory()?;
1353        let stmt = db.prepare("SELECT 1;")?;
1354        assert!(stmt.readonly());
1355        Ok(())
1356    }
1357
1358    #[test]
1359    #[cfg(feature = "modern_sqlite")] // SQLite >= 3.38.0
1360    fn test_error_offset() -> Result<()> {
1361        use crate::ffi::ErrorCode;
1362        let db = Connection::open_in_memory()?;
1363        let r = db.execute_batch("SELECT INVALID_FUNCTION;");
1364        match r.unwrap_err() {
1365            Error::SqlInputError { error, offset, .. } => {
1366                assert_eq!(error.code, ErrorCode::Unknown);
1367                assert_eq!(offset, 7);
1368            }
1369            err => panic!("Unexpected error {err}"),
1370        }
1371        Ok(())
1372    }
1373}