Struct Statement 

pub struct Statement { /* private fields */ }

A prepared SQL statement

Prepared statements parse SQL once at prepare time and retain the compiled plan. Subsequent executions use the plan directly, bypassing normalize, hash, and cache-lookup overhead on every call.

Thread Safety

Statement holds a weak reference to the Database and can be used from multiple threads, but each execution is serialized through the database’s executor lock.

Lifetime

The Statement becomes invalid when the Database is dropped. Attempting to use a Statement after its Database is dropped will return an error.

Implementations

impl Statement

pub fn execute<P: Params>(&self, params: P) -> Result<i64>

Execute the prepared statement

Returns the number of rows affected for DML statements.

Examples

let stmt = db.prepare("INSERT INTO users VALUES ($1, $2)")?;
stmt.execute((1, "Alice"))?;
stmt.execute((2, "Bob"))?;

pub fn query<P: Params>(&self, params: P) -> Result<Rows>

Query using the prepared statement

Returns an iterator over the result rows.

Examples

let stmt = db.prepare("SELECT * FROM users WHERE age > $1")?;

for row in stmt.query((18,))? {
    let row = row?;
    println!("{}", row.get::<String>("name")?);
}

pub fn query_one<T: FromValue, P: Params>(&self, params: P) -> Result<T>

Query and return a single value

Examples

let stmt = db.prepare("SELECT name FROM users WHERE id = $1")?;
let name: String = stmt.query_one((1,))?;

pub fn query_opt<T: FromValue, P: Params>(&self, params: P) -> Result<Option<T>>

Query and return an optional single value

Examples

let stmt = db.prepare("SELECT name FROM users WHERE id = $1")?;
let name: Option<String> = stmt.query_opt((999,))?;

pub fn sql(&self) -> &str

Get the SQL text of this statement

Trait Implementations

impl Clone for Statement

fn clone(&self) -> Statement

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.