add_some_data_and_query.go

package main

import (
	"fmt"

	"github.com/jackc/pgx"
)

func Connect(dsn string, maxConn int) *pgx.ConnPool {
	pgConfig, err := pgx.ParseURI(dsn)
	if err != nil {
		fmt.Sprintf("could not parse DSN: %s", dsn)
	}

	conn, err := pgx.NewConnPool(pgx.ConnPoolConfig{
		ConnConfig:     pgConfig,
		MaxConnections: maxConn,
	})
	if err != nil {
		fmt.Println("could not create connection pool")
	}

	return conn
}

func Query(db pgx.ConnPool) []string {
	q := `SELECT doc from public.jsonb_test;`
	fmt.Println(q)
	res := []string{}

	rows, err := db.Query(q)
	if err != nil {
		fmt.Sprintf("could not run query: %s", q)
	}
	defer rows.Close()

	for rows.Next() {
		var r string
		err = rows.Scan(&r)
		if err != nil {
			fmt.Println(err)
		}
		res = append(res, r)
	}
	return res
}

func Insert(db pgx.ConnPool) {
	q := `INSERT INTO public.jsonb_test (id, doc) VALUES ($1, $2)`
	stmt, err := db.Prepare("json_insert", q)
	if err != nil {
		fmt.Sprintf("could not create prepared statement: %s", q)
	}

	new_profile := `
     {
     "id": 4, "profileName": "Nana",
     "hobbies": ["yoyos"],
     "location": {"state": "OR", "zip": 97206, "cool": true}
     }
     `
	res, err := db.Exec(stmt.SQL, 4, new_profile)
	if err != nil {
		fmt.Sprintf("could not execute SQL: %s", q)
	}
	fmt.Println(res)
}

func main() {
	ip := ""
	dsn := fmt.Sprintf("postgres://demo_admin:postgres@%s:5432/demo", ip)
	pool := 5

	db := Connect(dsn, pool)

	fmt.Println(Query(*db))
        Insert(*db)
	fmt.Println(Query(*db))
}