【go筆記】使用sqlx操作MySQL
阿新 • • 發佈：2022-02-21
Go語言學習筆記之使用sqlx操作MySQL
前言
go在操作MySQL時，可以使用ORM（比如gorm、xorm），也可以使用原生sql。本文以使用sqlx為例，簡單記錄步驟。
- go version： 1.16
- 安裝相關庫
# mysql驅動
go get github.com/go-sql-driver/mysql
# 基於MySQL驅動的封裝
go get github.com/jmoiron/sqlx
- 連線MySQL
database, err := sqlx.Open("mysql", "username:password@tcp(127.0.0.1:3306)/dbName")
- 測試資料表定義：
CREATE TABLE `person` ( `user_id` INT(11) NOT NULL AUTO_INCREMENT, `username` VARCHAR(260) NULL DEFAULT NULL COLLATE 'utf8_general_ci', `sex` VARCHAR(260) NULL DEFAULT NULL COLLATE 'utf8_general_ci', `email` VARCHAR(260) NULL DEFAULT NULL COLLATE 'utf8_general_ci', PRIMARY KEY (`user_id`) USING BTREE ) COLLATE='utf8_general_ci' ENGINE=InnoDB AUTO_INCREMENT=2 ;
初始化MySQL連線
// 資料表person的結構體 type Person struct { UserId int `db:"user_id"` Username string `db:"username"` Sex string `db:"sex"` Email string `db:"email"` } func init() { // 初始化建立MySQL連線 database,err := sqlx.Open("mysql", "root:123456@tcp(127.0.0.1:3306)/gotest") if err != nil { fmt.Println("open mysql failed. ",err) return } // database.SetMaxOpenConns(200) // database.SetMaxIdleConns(10) db = database // defer db.Close() }
插入資料
func InsertData() { // 插入資料方式1 result,err := db.Exec("insert into person(username,sex,email) values(?,?,?)", "stu002", "woman", "[email protected]") if err != nil { fmt.Println("insert data failed, ",err) return } id, err := result.LastInsertId() if err != nil { fmt.Println("insert data failed2, ",err) return } fmt.Println("insert data success, ",id) } func InsertData2() { // 插入資料方式2 sqlStr := "insert into person(username,sex,email) values(:username,:sex,:email)" result,err := db.NamedExec(sqlStr,map[string]interface{}{ "username": "stu003", "sex": "man", "email": "[email protected]", }) if err != nil { fmt.Println("insert data failed, ",err) return } id, err := result.LastInsertId() if err != nil { fmt.Println("insert data failed2, ",err) return } fmt.Println("insert data success, ",id) }
刪除資料
func DeleteData() {
// delete 刪除資料
result,err := db.Exec("delete from person where username=? and sex=?","stu002","woman")
if err != nil {
fmt.Println("delete data failed, ",err)
return
}
row,err := result.RowsAffected()
if err != nil {
fmt.Println("affected row unknown, ",err)
}
fmt.Println("delete data success: ",row)
}
修改資料
func UpdateData() {
// update修改資料
result,err := db.Exec("update person set sex=? where username=?","woman","stu001")
if err != nil {
fmt.Println("update data failed, ",err)
return
}
row,err := result.RowsAffected()
if err != nil {
fmt.Println("affected row unknown, ",err)
}
fmt.Println("update data success: ",row)
}
查詢資料
func SelectData() {
// 查詢資料
var person Person
err := db.Get(&person, "select user_id,username,sex,email from person where user_id=?", 2)
if err != nil {
fmt.Println("select data failed, ",err)
return
}
fmt.Println(person.Email)
}
func SelectData2() {
// 查詢資料方式2
sqlStr := "select user_id,username,sex,email from person where user_id=:user_id"
rows,err := db.NamedQuery(sqlStr,map[string]interface{}{
"user_id": "2",
})
if err != nil {
fmt.Println("query data error, ",err)
return
}
for rows.Next() {
var person Person
if err := rows.StructScan(&person);err != nil {
fmt.Printf("struct scan failed, %v\n",err)
continue
}
fmt.Println(person)
}
}
事務操作
- 開啟事務：
func (db *DB) Begin() (*Tx, error)
- 回滾事務：
func (tx *Tx) Rollback() error
- 提交事務
func (tx *Tx) Commit() error
- 示例：
func InsertDataTransaction() {
tx,err := db.Begin()
if err != nil {
fmt.Println("transaction begin failed, ",err)
return
}
defer func() {
if p := recover(); p != nil {
_ = tx.Rollback()
panic(p)
} else if err != nil {
fmt.Printf("transaction rollback")
_ = tx.Rollback()
} else {
err = tx.Commit()
fmt.Printf("transaction commit")
return
}
}()
sqlStr := "insert into person(username,sex,email) values(?,?,?)"
result,err := tx.Exec(sqlStr,"stu004", "woman", "[email protected]")
if err != nil {
fmt.Println("insert data failed, ",err)
return
}
_,err = result.RowsAffected()
if err != nil {
fmt.Println("affected rows num is 0")
return
}
}
完整示例程式碼
package main
import (
"fmt"
_ "github.com/go-sql-driver/mysql"
"github.com/jmoiron/sqlx"
)
// 資料表person的結構體
type Person struct {
UserId int `db:"user_id"`
Username string `db:"username"`
Sex string `db:"sex"`
Email string `db:"email"`
}
// 資料表place的結構體
type Place struct {
Country string `db:"country"`
City string `db:"city"`
Telcode int `db:"telcode"`
}
var db *sqlx.DB
func init() {
// 初始化建立MySQL連線
database,err := sqlx.Open("mysql", "root:123456@tcp(127.0.0.1:3306)/gotest")
if err != nil {
fmt.Println("open mysql failed. ",err)
return
}
// database.SetMaxOpenConns(200)
// database.SetMaxIdleConns(10)
db = database
// defer db.Close()
}
func InsertData() {
// 插入資料
result,err := db.Exec("insert into person(username,sex,email) values(?,?,?)", "stu002", "woman", "[email protected]")
if err != nil {
fmt.Println("insert data failed, ",err)
return
}
id, err := result.LastInsertId()
if err != nil {
fmt.Println("insert data failed2, ",err)
return
}
fmt.Println("insert data success, ",id)
}
func InsertData2() {
// 插入資料
sqlStr := "insert into person(username,sex,email) values(:username,:sex,:email)"
result,err := db.NamedExec(sqlStr,map[string]interface{}{
"username": "stu003",
"sex": "man",
"email": "[email protected]",
})
if err != nil {
fmt.Println("insert data failed, ",err)
return
}
id, err := result.LastInsertId()
if err != nil {
fmt.Println("insert data failed2, ",err)
return
}
fmt.Println("insert data success, ",id)
}
func SelectData() {
// 查詢資料
var person Person
err := db.Get(&person, "select user_id,username,sex,email from person where user_id=?", 2)
if err != nil {
fmt.Println("select data failed, ",err)
return
}
fmt.Println(person.Email)
}
func SelectData2() {
// 查詢資料方式2
sqlStr := "select user_id,username,sex,email from person where user_id=:user_id"
rows,err := db.NamedQuery(sqlStr,map[string]interface{}{
"user_id": "2",
})
if err != nil {
fmt.Println("query data error, ",err)
return
}
for rows.Next() {
var person Person
if err := rows.StructScan(&person);err != nil {
fmt.Printf("struct scan failed, %v\n",err)
continue
}
fmt.Println(person)
}
}
func UpdateData() {
// update修改資料
result,err := db.Exec("update person set sex=? where username=?","woman","stu001")
if err != nil {
fmt.Println("update data failed, ",err)
return
}
row,err := result.RowsAffected()
if err != nil {
fmt.Println("affected row unknown, ",err)
}
fmt.Println("update data success: ",row)
}
func DeleteData() {
// delete 刪除資料
result,err := db.Exec("delete from person where username=? and sex=?","stu002","woman")
if err != nil {
fmt.Println("delete data failed, ",err)
return
}
row,err := result.RowsAffected()
if err != nil {
fmt.Println("affected row unknown, ",err)
}
fmt.Println("delete data success: ",row)
}
func InsertDataTransaction() {
tx,err := db.Begin()
if err != nil {
fmt.Println("transaction begin failed, ",err)
return
}
defer func() {
if p := recover(); p != nil {
_ = tx.Rollback()
panic(p)
} else if err != nil {
fmt.Printf("transaction rollback")
_ = tx.Rollback()
} else {
err = tx.Commit()
fmt.Printf("transaction commit")
return
}
}()
sqlStr := "insert into person(username,sex,email) values(?,?,?)"
result,err := tx.Exec(sqlStr,"stu004", "woman", "[email protected]")
if err != nil {
fmt.Println("insert data failed, ",err)
return
}
_,err = result.RowsAffected()
if err != nil {
fmt.Println("affected rows num is 0")
return
}
}
func main() {
// InsertData()
// InsertData2()
// SelectData()
// SelectData2()
// UpdateData()
// DeleteData()
InsertDataTransaction()
defer db.Close()
}