Golang操作Sqlite

0x00 引言

再简单的事情，也需要有人去做。

0x01 代码

package main

import (
	"database/sql"
	"fmt"
	_ "github.com/mattn/go-sqlite3"
	"os"
)

func main() {

	type Person struct {
		name string
		age int
	}

	person := Person{"mike",18}
	fmt.Println(person)

	os.Remove("./foo.db")
	db, err := sql.Open("sqlite3", "./foo.db")
	checkErr(err)
	defer db.Close()
	//插入数据
	_, err = db.Exec("create table userinfo (uid text not null primary key, username text, departname text, created text)")
	checkErr(err)

	stmt, err := db.Prepare("INSERT INTO userinfo(uid, username, departname, created) values(?,?,?,?)")
	checkErr(err)
	defer stmt.Close()
	res, err := stmt.Exec("1", "astaxie", "研发部门", "2012-12-09")
	checkErr(err)
	id, err := res.LastInsertId()
	checkErr(err)
	fmt.Println(id)

	//更新数据
	stmt, err = db.Prepare("update userinfo set username=? where uid=?")
	checkErr(err)
	defer stmt.Close()
	res, err = stmt.Exec("astaxieupdate", id)
	checkErr(err)
	affect, err := res.RowsAffected()
	checkErr(err)
	fmt.Println(affect)

	//查询数据
	rows, err := db.Query("SELECT * FROM userinfo")
	checkErr(err)
	defer rows.Close()
	for rows.Next() {
		var uid int
		var username string
		var department string
		var created string
		err = rows.Scan(&uid, &username, &department, &created)
		checkErr(err)
		fmt.Println(uid)
		fmt.Println(username)
		fmt.Println(department)
		fmt.Println(created)
	}

	//删除数据
	stmt, err = db.Prepare("delete from userinfo where uid=?")
	checkErr(err)
	defer stmt.Close()
	res, err = stmt.Exec(id)
	checkErr(err)
	affect, err = res.RowsAffected()
	checkErr(err)
	fmt.Println(affect)
	db.Close()
}

func checkErr(err error) {
	if err != nil {
		panic(err)
	}
}

0x02 错误处理

Golang 的这种检查错误的代码太多了，过度重复，一点都不优雅。Golang 2 对这种情况进行了改善。draft 给出的例子如下：

func main() {
	hex, err := ioutil.ReadAll(os.Stdin)
	if err != nil {
		log.Fatal(err)
	}

	data, err := parseHexdump(string(hex))
	if err != nil {
		log.Fatal(err)
	}

	os.Stdout.Write(data)
}

Golang 2的写法如下：

func main() {
	handle err {
		log.Fatal(err)
	}

	hex := check ioutil.ReadAll(os.Stdin)
	data := check parseHexdump(string(hex))
	os.Stdout.Write(data)
}

0x03 UPDATE

2019-01-15