Let's Say Here is Sample Code

LiveData Query

Query("SELECT IFNULL(COUNT(id),0) FROM Item WHERE status = :status")
fun getLiveData(status: Int): LiveData<Int>

Kotlin Flow Query

@Query("SELECT IFNULL(COUNT(id),0) FROM Item WHERE status = :status")
fun getFlowData(status: Int): Flow<Int>

So my Question is Flow gets new data if anything changes in the room database?

CodePudding user response：

Yes Flow gets new data if anything changes in the room database if you collect that flow of course, like the example below:

val flow = getFlowData(2) // type Flow<Int>
flow.collect { data ->
    // every time anything changes, the code inside collect is going to get called again
}

and also there is .first() that will give you only the latest data without live changes:

val data = getFlowData(2).first() // type Int

So it depends how you use Flow, and it depends on your needs.