DecisionTree Analytics & Services Data Analyst Interview Questions and Answers

Transposing a data set involves flipping rows and columns.

• Identify the data set to be transposed

• Create a new table with the columns and rows flipped

• Copy the data from the original table to the new table

• Transpose can be done using Excel, Python, R, SQL, etc.

• Example: Transposing a table of sales data to have products as rows and months as columns

SQL commands are used to manipulate and retrieve data from relational databases.

• SQL stands for Structured Query Language

• Common SQL commands include SELECT, INSERT, UPDATE, and DELETE

• SQL commands are used to create, modify, and delete database objects such as tables, views, and indexes

• Examples: SELECT * FROM customers; INSERT INTO orders (customer_id, order_date) VALUES (1, '2021-01-01'); UPDATE products SET price = 10....read more

The process outline involves identifying the problem, collecting and analyzing data, and presenting insights and recommendations.

• Identify the problem or question to be answered

• Collect relevant data from various sources

• Clean and preprocess the data

• Analyze the data using statistical methods and tools

• Visualize the data to identify patterns and trends

• Present insights and recommendations to stakeholders