更新数据

示例如下，省略数据库连接操作：

func updateWithParam(db * sql.DB){
        var err          error
        var result       sql.Result
        var rowsAffected int64
        var updateSQL    string = "update testcase1 set col2 = :1 where col1 = :2"
        var newStr       string = "hello world!"

        result, err = db.Exec(updateSQL, newStr, 10)
        getError(err)

        rowsAffected, err = result.RowsAffected()
        getError(err)
        fmt.Println(rowsAffected)
}