use postgres::{Client, NoTls, Error};fnmain() ->Result<(), Error> {letmut client =Client::connect("sa:sa@localhost:5435/test", NoTls)?; client.batch_execute(" CREATE TABLE IF NOT EXISTS author ( id SERIAL PRIMARY KEY, name VARCHAR NOT NULL, country VARCHAR NOT NULL ) ")?; client.batch_execute(" CREATE TABLE IF NOT EXISTS book ( id SERIAL PRIMARY KEY, title VARCHAR NOT NULL, author_id INTEGER NOT NULL REFERENCES author ) ")?;Ok(())}