Struct QueryResult

pub struct QueryResult {
    pub columns: Vec<String>,
    pub rows: Vec<RowResult>,
}

The result of a SQLite query issued with Connection::execute().

Examples

Load a set of rows from the default SQLite database, and iterate over them.

use spin_sdk::sqlite::{Connection, Value};

let db = Connection::open_default()?;

let query_result = db.execute(
    "SELECT * FROM users WHERE age >= ?",
    &[Value::Integer(min_age)]
)?;

let name_index = query_result.columns.iter().position(|c| c == "name").unwrap();

for row in &query_result.rows {
    let name: &str = row.get(name_index).unwrap();
    println!("Found user {name}");
}

Use the QueryResult::rows() wrapper to access a column by name. This is simpler and more readable but incurs a lookup on each access, so is not recommended when iterating a data set.

let db = Connection::open_default()?;
let query_result = db.execute(
    "SELECT * FROM users WHERE id = ?",
    &[Value::Integer(user_id)]
)?;
let name = query_result.rows().next().and_then(|r| r.get::<&str>("name")).unwrap();

Perform an aggregate (scalar) operation over a named SQLite database. The result set contains a single column, with a single row.

use spin_sdk::sqlite::Connection;

let db = Connection::open("customer-data")?;
let query_result = db.execute("SELECT COUNT(*) FROM users", &[])?;
let count = query_result.rows.first().and_then(|r| r.get::<usize>(0)).unwrap();

A result of a query

Fields

columns: Vec<String>

The names of the columns retrieved in the query

rows: Vec<RowResult>

the row results each containing the values for all the columns for a given row

Implementations

impl QueryResult

pub fn rows(&self) -> impl Iterator<Item = Row<'_>>

Get all the rows for this query result

Trait Implementations

impl Clone for QueryResult

fn clone(&self) -> QueryResult

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for QueryResult

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.