我正在玩Go，发现一个我无法解决的问题。假设我有如下代码：

// Imagine this is an external package for querying MySQL: I run a query 
// and it gives me back a struct with a method "Result" to get the result
// as a string
// I can NOT modify this code, since it is an external package
package bar

type MySQL struct {}

func (m *MySQL) RunQuery() *MySQLResult {
    return &MySQLResult{}
}

type MySQLResult struct {}

func (r *MySQLResult) Result() string {
    return "foo"
}

我导入了软件包并开始使用它：

// I created a little runner to help me
func run(m *bar.MySQL) string {
    return m.RunQuery().Result()
}

func main() {
    m := &bar.MySQL{}
    fmt.Println(run(m)) // Prints "foo"
}

我真的很喜欢我的助手“运行”，但是我想使其更加慷慨：我不希望人们总是向我传递MySQL客户端。可以是具有“ RunQuery”和“
Result”方法的任何东西。所以我尝试使用接口：

type AnyDB interface {
    RunQuery() interface{ Result() string }
}

func run(m AnyDB) string {
    return m.RunQuery().Result()
}

可悲的是，这不再编译了。我收到此错误：

cannot use m (type *MySQL) as type AnyDB in argument to run:
    *MySQL does not implement AnyDB (wrong type for RunQuery method)
        have RunQuery() *MySQLResult
        want RunQuery() interface { Result() string }

Go不支持此功能吗，或者我做错了什么？