I am using the tiberius crate for MSSQL Queries in Rust.

use tiberius::{Client, Config, AuthMethod};
use tokio::net::TcpStream;
use tokio_util::compat::TokioAsyncWriteCompatExt;
use anyhow::{ Result, Error };
use std::collections::HashMap;

#[tokio::main]
async fn main() -> Result<(), Error>{

    // create connection client and set up connection config
    let mut config = Config::new();
    config.host("my_server");
    config.port(1433);

    // use windows trusted authentication to connect
    config.authentication(AuthMethod::Integrated);
    config.trust_cert();

    // create a tcp stream using our configuration
    let tcp: TcpStream = TcpStream::connect(config.get_addr()).await?;
    tcp.set_nodelay(true)?;

    // create a SQL client
    let mut client = Client::connect(config, tcp.compat_write()).await?;
    let results = client.query("SELECT 'hello' AS foo, 'world' AS bar;", &[])
        .await?
        .into_results()
        .await?;

    let mut map: HashMap<String, String> = HashMap::new();
    for i in &results[0] {
        let foo: String = i.get("foo").unwrap().to_string();
        let bar: String = i.get("bar").unwrap().to_string();
        map.insert(
            foo,
            bar,
        );
    }

    Ok(())
}

I am basically running a oneshot query and want to read the values into a HashMap<String, String>.

I receive the following error in the get() call:

32 |         let foo: String = i.get("foo").unwrap().to_string();
   |                             ^^^ cannot infer type of the type parameter `R` declared on the method `get`

Based on the docs, I am not sure I understand this error.