MySQL database operation in go Language (ii)

Connection pool

The go language comes with a database connection pool, which can be used directly and conveniently.

func init() {    db, _ = sql.Open("mysql", "root:[email protected](127.0.0.1:3306)/betting?charset=utf8")    // 设置最大打开的连接数，默认值为0表示不限制。    db.SetMaxOpenConns(2000)    // 用于设置闲置的连接数。    db.SetMaxIdleConns(1000)    db.Ping()}

• By setting the maximum number of connections, you can avoid too many connections errors that occur when you connect to MySQL with too high concurrency.
• Set the number of idle connections when a connection is opened, it can be placed in the pool for the next use.

Call a stored procedure

When I use go to invoke a stored procedure, how to get the value in the Out parameter and never find the correct method, I only summarize the method using the in parameter.

Stored Procedures

CREATE DEFINER = ‘root‘@‘localhost‘ PROCEDURE `proc_test`(        IN `in_id` INTEGER    )    NOT DETERMINISTIC    CONTAINS SQL    SQL SECURITY DEFINER    COMMENT ‘‘BEGIN    SELECT log_ip FROM admin_log WHERE id=in_id;END;

Call in Go

func main() {    db, err := sql.Open("mysql", "root:[email protected](127.0.0.1:3306)/betting?charset=utf8")    checkError("连接数据库", err)    defer db.Close()    var outArg string    row := db.QueryRow("call proc_test(?)", 2000)    row.Scan(&outArg)    fmt.Println(outArg)}

Execution results

192.168.88.91

MySQL database operation in go Language (ii)