Struct CachedStatement 

pub struct CachedStatement { /* private fields */ }

A prepared statement suitable for caching and re-execution. A prepared statement that can be reset and re-executed with different bindings.

Unlike Statement, CachedStatement is not tied to a connection’s lifetime. It remains valid as long as the underlying database is open.

This type is used by Diesel statement cache (StatementCache<DuckDb, CachedStatement>).

Implementations

impl CachedStatement

pub fn prepare(conn: &RawConnection, sql: impl AsRef<str>) -> Result<Self>

Prepares sql against the given connection.

Errors

Returns Error::DuckDBFailure if DuckDB cannot parse or plan the query, or Error::NulError if sql contains an interior nul byte.

pub fn reset_bindings(&mut self) -> Result<()>

Resets all parameter bindings so the statement can be re-executed.

Errors

Returns Error::DuckDBFailure if the DuckDB clear-bindings call fails.

pub fn bind<T: AppendAble + ?Sized>( &mut self, idx: u64, value: &mut T, ) -> Result<()>

Binds value at the given 1-based parameter index.

Errors

Returns an error if the underlying DuckDB bind call fails or idx is out of range.

pub fn execute(&mut self) -> Result<DuckResult>

Executes the prepared statement and returns the result.

Works for all statement types:

• SELECT — iterate rows via the Iterator impl on DuckResult.
• INSERT / UPDATE / DELETE — check DuckResult::changes() for affected rows.
• DDL (CREATE TABLE etc.) — .changes() returns 0, no rows to iterate.
• INSERT … RETURNING — iterate rows and/or call .changes().

Errors

Returns Error::DuckDBFailure if execution fails.

Trait Implementations

impl Drop for CachedStatement

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.

impl Send for CachedStatement