How to execute two observables sequentially?

android, rx-java

Solution

This is what concat operator does - it executes sequentially given Observables - another Observable won't start until previous one gets completed

Observable.concat(dataBaseObservable, networkRequestObservable)
          .subscribe(Data -> {
              // do something with data
          });

Problem

How to execute two observables sequentially and overwrite one result by another in rxjava chain? For example i have got data1 = observableFromDb and data2 = observableFromServer; I would like to combine them in chain and overwrite data1 by data2 result.

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