Marsh McLennan Data Analyst Interview Questions and Answers

Q1. Load data from hdfs using python
Ans. 
Use PyArrow library to load data from HDFS in Python
• Install PyArrow library using pip install pyarrow

• Use pyarrow.hdfs.connect to connect to HDFS

• Use pyarrow.parquet.read_table to read data from HDFS
Answered by AI
Add your answer
Q2. Query to find the top three salaried employees of each department
Ans. 
Query to find the top three salaried employees of each department
• Use a SQL query with a window function like ROW_NUMBER() to rank employees within each department based on salary

• Partition the data by department and order by salary in descending order

• Filter the results to only include rows where the row number is less than or equal to 3
Answered by AI
Add your answer

Q1. What is p value?
Ans. 
A p-value is a measure used in statistical hypothesis testing to determine the strength of evidence against the null hypothesis.
• A p-value is the probability of obtaining results as extreme as the observed results, assuming the null hypothesis is true.

• A p-value is compared to a significance level (usually 0.05) to determine if the null hypothesis should be rejected.

• A p-value less than the significance level indicates st
Answered by AI
Add your answer
Q2. Tell the output a**2
Ans. 
The output of a**2 is the square of the value of a.
• The output is the value of a multiplied by itself

• For example, if a = 3, then the output would be 9 (3*3)
Answered by AI
Add your answer
Q3. Difference between append() and concat
Ans. 
append() adds elements to a single DataFrame, while concat() combines multiple DataFrames.
• append() is a method used to add rows to a DataFrame.

• concat() is a function used to combine multiple DataFrames along a particular axis.

• append() modifies the original DataFrame, while concat() returns a new DataFrame.

• Example: df1.append(df2) vs pd.concat([df1, df2])
Answered by AI
Add your answer

Q1. Question related to SQL.
Add your answer
Q2. Concept of Data Warehousing.
Ans. 
Data warehousing is the process of collecting, storing, and managing data from various sources for analysis and reporting.
• Data warehousing involves extracting data from multiple sources and consolidating it into a central repository.

• It is used for analytical reporting, business intelligence, and decision-making purposes.

• Data warehouses are designed for query and analysis rather than transaction processing.

• Examples of d...read more
Answered by AI
Add your answer

Q1. Questions on DBMS,ML,SQL,PLSQL,OOPS
Add your answer
Q2. What is polymorphism
Ans. 
Polymorphism is the ability of a function or method to behave differently based on the object it is acting upon.
• Polymorphism allows objects of different classes to be treated as objects of a common superclass.

• It enables a single interface to be used for different data types or classes.

• Examples include method overloading and method overriding in object-oriented programming.
Answered by AI
Add your answer
Q3. Polymorphism is abstraction in object oriented lagnguage used for providing too may forms to single entity
Add your answer
Q4. What is the major issue you faced inml project
Add your answer
Q5. What is your biggest strength
Add your answer

40 questions are there. The que have different categories. Reasoning , critical thinking

Q1. Tell me about your self
Add your answer
Q2. Question based on the resume
Add your answer
Q3. What are the project you have done?
Add your answer

Tuff question paper

Q1. Random questions for you and your family
Add your answer
Q2. Tell your background
Add your answer
Q3. Tell me your education
Add your answer
Q4. Tell me about yourself
Add your answer
Q5. How much expect salary
Add your answer