mysql簡單示例

趁現在公司的事情沒那麼多，多寫幾篇吧，雖然都比較基礎，但是寫了總比不寫好。
mysql大家應該都瞭解，一款非常流行的開源關係資料庫應用，而go語言中mysql的庫不是很多，其中使用的人最多的應該就是go-sql-driver/mysql了吧，我的專案中同樣也用了這個庫，同樣貼出它的github倉庫地址
go-sql-driver/mysql
下面貼一下用go-sql-driver/mysql操作資料庫的簡單例子的程式碼，非常基礎，直接看註釋就好。

package main

import (
    "database/sql"
    "fmt"
    _ "github.com/go-sql-driver/mysql"
 

)

func main() {
    //db配置資訊
    user := "root"
    psw := "jiandanmima"
    host := "localhost"
    port := 3306
    dbname := "testdb"
    charset := "utf8"
    config := fmt.Sprintf("%s:%[email protected](%s:%d)/%s?charset=%s", user, psw, host, port, dbname, charset)
    //連線資料庫，獲取連線例項
    db, err := sql.Open("mysql"
 
, config)
    if err != nil {
        fmt.Println("open db error", err)
    }
    //設定最大閒置連線和最大開啟連線，具體數值按需指定
    db.SetMaxIdleConns(32)
    db.SetMaxOpenConns(32)

    //增刪改查操作
    err = Insert(db, "劉小明", "男", 18)
    if err != nil {
        fmt.Println("insert err", err)
    }
    err = Delete(db, 1)
    if
 
 err != nil {
        fmt.Println("delete err", err)
    }
    err = Update(db, 2, 22)
    if err != nil {
        fmt.Println("update err", err)
    }
    err = Select(db, 3)
    if err != nil {
        fmt.Println("select err", err)
    }
    err = SelectAll(db)
    if err != nil {
        fmt.Println("select all err", err)
    }
}

//增
func Insert(db *sql.DB, name string, sex string, age int) error {
    sen := "INSERT INTO people(name, sex, age) VALUES (?, ?, ?)"
    stmt, err := db.Prepare(sen)
    if err != nil {
        return err
    }
    defer stmt.Close() //預處理記得關閉連線，使用defer在函式return前關閉
    rst, err := stmt.Exec(name, sex, age)
    if err != nil {
        return err
    }
    lastId, err := rst.LastInsertId()
    if err != nil {
        return err
    }
    fmt.Printf("last insert id %d.\n", lastId)
    return nil
}

//刪
func Delete(db *sql.DB, id int) error {
    sen := "DELETE FROM people WHERE id = ?"
    stmt, err := db.Prepare(sen)
    if err != nil {
        return err
    }
    defer stmt.Close()
    rst, err := stmt.Exec(id)
    if err != nil {
        return err
    }
    rowsAffected, err := rst.RowsAffected()
    if err != nil {
        return err
    }
    fmt.Printf("%d records has been deleted.\n", rowsAffected)
    return nil
}

//改
func Update(db *sql.DB, id int, age int) error {
    sen := "UPDATE people SET age = ? WHERE id = ?"
    stmt, err := db.Prepare(sen)
    if err != nil {
        return err
    }
    defer stmt.Close()
    rst, err := stmt.Exec(age, id)
    if err != nil {
        return err
    }
    rowsAffected, err := rst.RowsAffected()
    if err != nil {
        return err
    }
    fmt.Printf("%d records has been updated.\n", rowsAffected)
    return nil
}

//查
func Select(db *sql.DB, id int) error {
    sen := "SELECT name, sex, age FROM people WHERE id = ?"
    stmt, err := db.Prepare(sen)
    if err != nil {
        return err
    }
    defer stmt.Close()
    row := stmt.QueryRow(id)
    var name, sex string
    var age int
    row.Scan(&name, &sex, &age)
    fmt.Printf("the information of id %d: name = '%s', sex = '%s', age = %d.\n", id, name, sex, age)
    return nil
}

//查詢多條記錄
func SelectAll(db *sql.DB) error {
    sen := "SELECT id, name, sex, age FROM people ORDER BY id"
    stmt, err := db.Prepare(sen)
    if err != nil {
        return err
    }
    defer stmt.Close()
    rows, err := stmt.Query()
    if err != nil {
        return err
    }
    defer rows.Close() //查詢多條記錄的rows介面卡也需要及時關閉
    fmt.Println("all information of table people:")
    fmt.Println("id   name   sex   age")
    for rows.Next() {
        var id, age int
        var name, sex string
        rows.Scan(&id, &name, &sex, &age)
        fmt.Printf("%d   %s   %s   %d\n", id, name, sex, age)
    }
    return nil
}

程式執行前的資料表資料

程式執行的輸出結果

最後附上資料表建立和資料插入語句

CREATE TABLE `people` (
  `id` int(11) NOT NULL AUTO_INCREMENT COMMENT '自增id',
  `name` varchar(255) NOT NULL DEFAULT '' COMMENT '姓名',
  `sex` varchar(8) NOT NULL DEFAULT '男' COMMENT '性別',
  `age` int(11) NOT NULL DEFAULT '0' COMMENT '年齡',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

insert into people(name, sex, age) values('張全蛋', '男' , 18), ('趙鐵根', '男', 19), ('李小花', '女', 20), ('王尼瑪', '男', 36);

golang簡單的mysql操作就在這了。