使用mysql+kafka模式。用JMeter模拟1W数据2秒启动100个线程，循环100次，JMeter界面8s左右请求完毕，然后查看消费端，消费的很慢1s就三四十条左右，应该是发送端发送的慢，和这个测试基本一样 #416

It would be useful if ksqlDB had a NULLIF function, as common across SQL in other platforms.

Example from postgres:

NULLIF(value1, value2)
The NULLIF function returns NULL if and only if value1 and value2 are equal. Otherwise it returns value1.

Currently, you are not able to use middleware per handler in "clean way" (you can still manually wrap the handler function, or have separated router).

It would be nice to be able to add middleware per handler.

As a good reference point, you can use chi router: https://github.com/go-chi/chi

我看到可以通过Prometheus搭建监控环境，如果有图文，更容易理解．