func connInsert(db *sql.DB){
var err error
var result sql.Result
var conn * sql.Conn
var val1 int = 10
var val2 string = "hello!"
var rowsAffected int64
ctx, cancel := context.WithTimeout(context.Background(), 55*time.Second)
defer cancel()
//从连接池中返回一个连接
conn, err = db.Conn(ctx)
getError(err)
//将连接返回到连接池中
defer conn.Close()
result, err = conn.ExecContext(ctx, `insert into testcase1(col1, col2) values(:1 , :2)`, val1, val2)
getError(err)
//获取执行影响行数
rowsAffected, err = result.RowsAffected()
fmt.Println(rowsAffected)
}