Function main

21_postgresql/rust/pg_async/src/main.rs:38–80

()

#[tokio::main]
async fn main() -> Result<(), Error> {
    let (mut client, connection) =
        tokio_postgres::connect("host=localhost user=htd", NoTls).await?;

    // connection object performs communication with DB, spawned to run on its own
    tokio::spawn(async move {
        if let Err(e) = connection.await {
            eprintln!("connection error: {}", e);
        }
    });

    let rows = client.query(MOST_RECOVERED, &[]).await?;

    let value: chrono::NaiveDate = rows[0].get(0);
    println!("{:?}", value);
    println!("{:?}", row_to_str_vec(&rows[0]).await);
    println!("{:?}", row_to_str_hashmap(&rows[0]).await);

    let transaction = client.transaction().await?;
    transaction.query("DELETE FROM month_cases", &[]).await?;
    let ins_mv = transaction
        .prepare(
            "INSERT INTO month_cases
            (mon, new_cases, recovered)
            VALUES ($1, $2, $3)",
        )
        .await?;

    for row in transaction.query(GROUP_BY_MONTH, &[]).await? {
        println!("{:?}", row_to_str_vec(&row).await);
        let date: chrono::NaiveDate = row.get(0);
        let new_cases: i64 = row.get(1);
        let recovered: i64 = row.get(2);
        transaction
            .execute(
                &ins_mv,
                &[&date.to_string(), &(new_cases as i32), &(recovered as i32)],
            )
            .await?;
    }
    transaction.commit().await?;
    Ok(())
}