Interview Questions

In today’s AI-driven world, we often turn to AI for help with solving problems. It can offer ideas, analyze information, and suggest different approaches. But it is still up to us to decide which approach is most effective, organize the workflow, and guide the process toward the right solution.

AI suggests number of ways but human has to choose the effective one.

The following are basic problem-solving questions that interviewers may ask at random to assess an interviewee’s fundamental understanding. They are available on the StrataScratch platform.

Duplicate HR Department Employees

Generate a list of employees who work in the HR department, including only their first names and department in the output. Each employee should appear twice in the list, meaning their first name and department should be duplicated in the output.

DataFrame

worker

worker

worker_id:int64

first_name:object

last_name:object

salary:int64

joining_date:datetime64[ns]

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department:object

Steps to solve the Question:

1. Find all the employees where department is HR.
2. List all employees which appear twice in the list .

Using Python-Pandas

import pandas as pd
worker.head()
df= worker
df=df[df['department']=='HR']
df1=df.loc[df.index.repeat(2)]

df1[['first_name','department']]

Using MySQL

select first_name, department from worker where department Like 'HR'
UNION ALL
select first_name, department from worker where department Like 'HR' 
order by first_name;

Output:

Employees With the Same Salary

Find employees who earn the same salary.

Output the worker id along with the first name and the salary in descending order.

DataFrame is same as former problem

Steps to solve this question

1. Find the employees who are having the same salary.
2. Then sort the values in descending order.

Using Python-Pandas

import pandas as pd
worker.head()
df=worker
df=df[df.duplicated(subset=['salary'],keep=False)]
df=df.sort_values(by='salary',ascending=False)
df[['worker_id','first_name','salary']]

Duplicated Function is used to find out duplicate values based on salary in a DataFrame and keep parameter helps in having both values in the output.

Using MySQL

SELECT worker_id, first_name, salary
FROM worker
WHERE salary IN (
    SELECT salary 
    FROM worker 
    GROUP BY salary 
    HAVING COUNT(*) > 1
)
ORDER BY salary desc;