added async_pg example

async_pg/sql/add_user.sql

@@ -0,0 +1,3 @@
+INSERT INTO testing.users(email, first_name, last_name, username)
+VALUES ($1, $2, $3, $4)
+RETURNING $table_fields;

async_pg/sql/create_db.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+
+psql -U postgres -h 127.0.0.1 -f setup_db_and_user.sql

async_pg/sql/get_users.sql

@@ -0,0 +1 @@
+SELECT $table_fields FROM testing.users;

async_pg/sql/setup_db_and_user.sql

@@ -0,0 +1,20 @@
+DROP DATABASE IF EXISTS testing_db;
+
+CREATE USER test_user WITH PASSWORD 'testing';
+
+CREATE DATABASE testing_db OWNER test_user;
+
+\connect testing_db;
+
+DROP SCHEMA IF EXISTS testing CASCADE;
+CREATE SCHEMA testing;
+
+
+CREATE TABLE testing.users (
+	id  BIGSERIAL PRIMARY KEY,
+	email       VARCHAR(200) NOT NULL,
+	first_name  VARCHAR(200) NOT NULL,
+	last_name   VARCHAR(200) NOT NULL,
+	username    VARCHAR(50) UNIQUE NOT NULL,
+	UNIQUE (username)
+);