Senior Analytics Consultant Interview Questions and Answers

Finding common elements between two strings in Python.

• Convert the strings into sets and use the intersection method to find common elements.

• Iterate through each character in one string and check if it exists in the other string.

• Use the difflib library to find the longest common substring between two strings.

To remove duplicate rows in SQL, use the DISTINCT keyword or a DELETE statement with a CTE or subquery.

• Use SELECT DISTINCT to retrieve unique rows: SELECT DISTINCT column1, column2 FROM table_name;

• To delete duplicates, use a Common Table Expression (CTE): WITH CTE AS (SELECT *, ROW_NUMBER() OVER (PARTITION BY column1 ORDER BY column2) AS rn FROM table_name) DELETE FROM CTE WHERE rn > 1;

• Another method is using a temporary table: CREATE TABLE temp_table AS SELECT DISTINCT * FRO...read more

Different types of joins in SQL include INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN. TRUNCATE is faster than DELETE as it removes all rows at once.

• Types of joins: INNER JOIN, LEFT JOIN, RIGHT JOIN, FULL JOIN

• TRUNCATE: removes all rows from a table without logging individual row deletions

• DELETE: removes specific rows from a table and logs each row deletion

• TRUNCATE is faster than DELETE as it does not log individual row deletions

Presented key data insights on patient outcomes to stakeholders, driving strategic decisions in a healthcare project.

• Analyzed patient data from a recent clinical trial, identifying trends in treatment efficacy.

• Created a comprehensive presentation highlighting key metrics, such as recovery rates and side effects.

• Engaged stakeholders by tailoring insights to their specific interests, ensuring relevance and clarity.

• Facilitated a Q&A session post-presentation, addressing concerns...read more

LOD expressions in Tableau allow you to compute values at different levels of detail in a visualization.

• LOD expressions include FIXED, INCLUDE, and EXCLUDE functions

• FIXED LOD expressions compute values at a specific level of detail regardless of the visualization level

• INCLUDE LOD expressions compute values at the specified level of detail and include other dimensions in the visualization

• EXCLUDE LOD expressions compute values at the specified level of detail while excluding ot...read more

Blending and joins in Tableau allow users to combine data from multiple sources for analysis and visualization.

• Blending is used when data sources have a common field but different levels of granularity.

• Joins are used when data sources have a common field and the same level of granularity.

• Blending creates a virtual join, while joins physically combine the data.

• Examples: Blending sales data from Excel with customer data from a database, joining employee data from two different ...read more

Filters in Tableau allow users to focus on specific data points within a visualization.

• Filters can be applied to dimensions or measures to narrow down the data being displayed.

• Users can use various types of filters such as quick filters, context filters, and data source filters.

• Filters can be used to show or hide data based on specific criteria, such as date ranges or categories.

• Example: Applying a filter to show only sales data from a specific region.