Data engineer Interview Questions

2years

I have no experience

Map>> ret = mappy.entrySet().stream(). collect( Collectors.groupingBy( x -> x.getValue())); Map result = ret.entrySet().stream().collect ( Collectors.toMap( x -> x.getKey(), y -> y.getValue().stream().map( p -> p.getKey()).collect(Collectors.joining(",")))); System.out.println(result);

d = {'A': 10, 'B': 5, 'C': 5, 'D': 12, 'E': 3} d2 = {} for k, v in d.items(): if d2.get(v, '') == '': d2[v] = k else: d2[v] = "{}, {}".format(d2[v], k) for k, v in d2.items(): print "{}: {}".format(k, v)

Good

It's essential to demonstrate that you can really go deep... there are plenty of followup questions and (sometimes tangential) angles to explore. There's a lot of Data Engineer experts who've worked at OakNorth, who provide this sort of practice through mock interviews. There's a whole list of them curated on Prepfully. prepfully.com/practice-interviews

hadoop for fs hadoop 2 for dfs

Simple answers

The interviewer is trying to see if you know of Pythons list comprehension rather than running nested loops.

plenty of stock responses online, seemed like an afterthought