golang postgresql CRUD
package main import ( "database/sql" "fmt" "log" _ "github.com/lib/pq" // postgres driver ) // People - database type People struct { id int name string age int } type appContext struct { db *sql.DB } // ConnectDB connect specify database func connectDB(driverName string, dbName string) (c *appContext, errorMessage string) { db, err := sql.Open(driverName, dbName) if err != nil { return nil, err.Error() } if err = db.Ping(); err != nil { return nil, err.Error() } return &appContext{db}, "" } // Create func (c *appContext) Create() { // get insert id lastInsertId := 0 err := c.db.QueryRow("INSERT INTO users(name,age) VALUES($1,$2) RETURNING id", "jack", 22).Scan(&lastInsertId) if err != nil { log.Fatal(err) } fmt.Println("inserted id is ", lastInsertId) } // Read func (c *appContext) Read() { rows, err := c.db.Query("SELECT * FROM users") if err != nil { fmt.Println(err.Error()) return } defer rows.Close() for rows.Next() { p := new(People) err := rows.Scan(&p.id, &p.name, &p.age) if err != nil { fmt.Println(err) } fmt.Println(p.id, p.name, p.age) } } // UPDATE func (c *appContext) Update() { stmt, err := c.db.Prepare("UPDATE users SET age = $1 WHERE id = $2") if err != nil { log.Fatal(err) } result, err := stmt.Exec(10, 1) if err != nil { log.Fatal(err) } affectNum, err := result.RowsAffected() if err != nil { log.Fatal(err) } fmt.Println("update affect rows is ", affectNum) } // DELETE func (c *appContext) Delete() { stmt, err := c.db.Prepare("DELETE FROM users WHERE id = $1") if err != nil { log.Fatal(err) } result, err := stmt.Exec(1) if err != nil { log.Fatal(err) } affectNum, err := result.RowsAffected() if err != nil { log.Fatal(err) } fmt.Println("delete affect rows is ", affectNum) } // Mypg - Postgresql CRUD func main() { c, err := connectDB("postgres", "user=user1 password=password1 dbname=exampledb") defer c.db.Close() if err != "" { print(err) } c.Create() fmt.Println("add action done!") c.Read() fmt.Println("get action done!") c.Update() fmt.Println("update action done!") c.Delete() fmt.Println("delete action done!") }