golang mysql update

import (

"database/sql"

"fmt"

_"github.com/go-sql-driver/mysql"

)

func main() {

db, err := sql.Open("mysql", "root:0314@tcp(127.0.0.1:3306)/golang_test?charset=utf8")

checkErr(err)

defer db.Close()

// insert(db)

// query(db)

// update(db)

// delete(db)

}

// insert

func insert(db *sql.DB) {

stmt, err := db.Prepare("INSERT user (name, age) values (?,?)")

checkErr(err)

res, err := stmt.Exec("Eric", 22)

checkErr(err)

id, err := res.LastInsertId()

checkErr(err)

fmt.Printf("insert id=%d\n", id)

}

// query

func query(db *sql.DB) {

rows, err := db.Query("SELECT * FROM user")

checkErr(err)

// 列，字段名

columns, err:= rows.Columns()

checkErr(err)

scanArgs := make([]interface{}, len(columns))

values := make([]interface{}, len(columns))

for i := range values {

scanArgs[i] = &values[i]

}

for rows.Next() {

err = rows.Scan(scanArgs...)

checkErr(err)

// 行，记录

record := make(map[string]string)

for i, col := range values {

if col != nil {

record[columns[i]] = string(col.([]byte))

}

fmt.Println(record)

}

}

}

// update

func update(db *sql.DB) {

stmt, err := db.Prepare("UPDATE user SET name=?,age=? WHERE id=?")

checkErr(err)

res, err := stmt.Exec("Rose", 21, 1)

checkErr(err)

num, err := res.RowsAffected()

fmt.Printf("affected：%d\n", num)

}

// delete

func delete(db *sql.DB) {

stmt, err := db.Prepare("DELETE FROM user WHERE id=?")

checkErr(err)

res, err := stmt.Exec(1)

checkErr(err)

num, err := res.RowsAffected()

fmt.Printf("affected：%d\n", num)

}

func checkErr(err error) {

if err != nil {

panic(err)

}

}