关于client多协程问题

[always-waiting]

下面是一个示例

package main

import (
	"fmt"
	"github.com/siddontang/go-mysql/client"
	"sync"
)

const (
	SQL1 = "select device_sn from t_device_basic where id = ? and is_delete = 0"
)

func main() {
	fmt.Println("vim-go")
	cli, err := client.Connect(
		"localhost:3306",
		"root",
		"abc123",
		"db_cmdb",
	)
	if err != nil {
		panic(err)
	}
	fmt.Println("test")
	var wg sync.WaitGroup
	for _, id := range []int{1, 2, 3, 4, 5} {
		wg.Add(1)
		go func(i int) {
			defer wg.Done()
			res, err := cli.Execute(SQL1, i)
			if err != nil {
				fmt.Printf("%d查询出错:%v\n", i, err)
				return
			}
			num := res.RowNumber()
			for n := 0; n < num; n++ {
				var get string
				get, err := res.GetStringByName(n, "device_sn")
				if err != nil {
					fmt.Printf("获取第%d的sn出错", n)
				}
				fmt.Println(get)
			}
		}(id)
	}
	wg.Wait()
}

如上，希望可以只用一个mysql链接，给多个协程进行处理，这时会出如下错误:

vim-go
test
5查询出错:invalid sequence 1 != 3
2查询出错:invalid sequence 0 != 3
4查询出错:invalid sequence 1 != 3
1查询出错:invalid sequence 0 != 3
3查询出错:invalid sequence 2 != 1

除了加锁调用，是否还能有其他解决方案呢？

[always-waiting]

@siddontang
这个问题，能够从包层面进行优化吗?

[siddontang]

一个 conn 只能用在一个 goroutine，不支持并发访问

[meshenka]

can you translate your response @siddontang i also encounters invalid sequence 63 != 1 while doing some select

[always-waiting]

@meshenka

He means that the client of db does not support concurrency. If one client is used by many goroutines, this problem will arise

[meshenka]

@meshenka

He means that the client of db does not support concurrency. If one client is used by many goroutines, this problem will arise

ha yes ok, i. got the same issue and moved from your client to to database/sql to fix my query calls, much faster btw.

thanks