Added more about pgx in golang

examples/golang/cource/06g_databases/postgres.go

@@ -7,8 +7,8 @@ import (
 	"context"
 	"os"
 	"github.com/jackc/pgx/v4"
-//	"github.com/jackc/pgx/v4/pgxpool"
-//	"github.com/georgysavva/scany/pgxscan"
+	"github.com/jackc/pgx/v4/pgxpool"
+	"github.com/georgysavva/scany/pgxscan"
 )
 
 func PostgresSimpleQuery() (name string, position string) {
@@ -30,6 +30,74 @@ func PostgresSimpleQuery() (name string, position string) {
 	return name, position
 }
 
+func PostgresScanToObject() {
+	ctx := context.Background()
+	db, err := pgxpool.Connect(ctx, "postgres://postgres:some@localhost:5432/postgres")
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Can't connect to db: %v\n", err)
+		os.Exit(1)
+	}
+
+	type User struct {
+		Name string
+		Rank string
+		Id int
+	}
+	defer db.Close()
+
+	var users []User
+	pgxscan.Select(ctx, db, &users, "select * from users")
+	fmt.Println(users)
+
+	var user User
+	pgxscan.Get(ctx, db, &user, "select * from users where id=$1", 2)
+	fmt.Println(user)
+}
+
+func PostgresJoinQuery() {
+	ctx := context.Background()
+	db, err := pgxpool.Connect(ctx, "postgres://postgres:some@localhost:5432/postgres")
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Can't connect to db: %v\n", err)
+		os.Exit(1)
+	}
+	defer db.Close()
+
+	query := "SELECT users.name, users.rank, cr.brand, cr.colour, cr.license_plate "+
+				"FROM users "+
+				"JOIN cars cr ON users.id = cr.user_id "+
+				"WHERE users.rank = $1"
+
+	type UserCar struct {
+		Name string
+		Rank string
+		Brand string
+		Colour string
+		LicensePlate string
+	}
+	var carBounds []UserCar
+
+	pgxscan.Select(ctx, db, &carBounds, query, "Manager")
+	fmt.Println(carBounds)
+}
+
+func PostgresAddCar(userId int, colour string, brand string, licensePlate string) {
+	ctx := context.Background()
+	conn, err := pgx.Connect(ctx, "postgres://postgres:some@localhost:5432/postgres")
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "Can't connect to db: %v\n", err)
+		os.Exit(1)
+	}
+	defer conn.Close(ctx)
+
+	_, err = conn.Exec(ctx, "INSERT INTO cars(user_id, colour, brand, license_plate) "+
+							"VALUES ($1,$2,$3,$4)", userId, colour, brand, licensePlate)
+	fmt.Println(err)
+}
+
 func main() {
 	fmt.Println(PostgresSimpleQuery())
+	PostgresScanToObject()
+	PostgresJoinQuery()
+//	PostgresAddCar(1,"SomeShit","Kaiyi","A666G4")
 }

examples/golang/cource/06g_databases/postgres.sql

@@ -4,7 +4,7 @@ CREATE TABLE users (
     rank VARCHAR(255)
 );
 
-CREATE UNIQUE INDEX users_id_uindex ON cars(id);
+CREATE UNIQUE INDEX users_id_uindex ON users(id);
 
 CREATE TABLE cars (
     id SERIAL PRIMARY KEY,