Apache Flink

Hello everyone, I would like to know if I can output the result of datastream.addSource() to a collection? For example, List or Map, so that I can use it in another stream. For example, read the name from the database through a datastream and store it in a list, and then filter the data based on this name in a loop.

It seems like you could do that via connecting the two streams via the `connect()` function based on constructing a stream from the elements you read from the database:
```// Get your names
val names = getNamesFromDatabase()
// Create a stream of your names
val nameStream = streamEnv.fromElements(names)

// Join your existing source with your names and do something
streamEnv
    .fromDataSource(...)
    .connect(nameStream)
    .process(DoSomethingFunction())```
There are lots of ways to accomplish this depending on how you want to construct your job, timing, etc. but this is a very naive way to join two separate streams.

```Okay, thank you for your suggestion, I'll give it a try and let you know if it works.```
