Looking to start a career in data analysis? If so, you’ll likely need to go through a data analyst interview. This can be daunting, but don’t worry – we’re here to help! In this blog post, we will discuss some of the most common dax interview questions and how to answer them. Let’s get started!
1. What is DAX?
Ans. DAX (Data Analysis Expressions) is a language used for data analysis and reporting. It can be used to calculate values, create measures, and filter data. DAX is often used in conjunction with Power BI, a data visualization tool.
2. What are some of the most common DAX functions?
Ans. Some of the most common DAX functions include: CALCULATE(), SUM(), AVERAGE(), and COUNT(). These functions can be used to calculate values, sums, averages, and counts within your data.
3. How can I use DAX to filter data?
Ans. DAX can be used to filter data in a number of ways. You can use the FILTER() function to return a subset of data based on certain criteria, the CALCULATE() function to calculate values within a filtered dataset, and the ALL() function to return all rows from a dataset.
4. What are DAX Queries?
Ans. DAX Queries are a way of filtering and grouping data in Power BI. They allow you to filter data by column, calculate values, and group data by column. DAX Queries can be used to create dynamic reports in Power BI.
5. How can I use DAX to create measures?
Ans. DAX can be used to create measures in a number of ways. You can use the MEASURES() function to return a list of all measures within a dataset, the CALCULATE() function to calculate values within a measure, and the FILTER() function to filter data within a measure.
6. What is the difference between calculated columns and measures?
Ans. Calculated columns are created by using the Excel formula bar while measures are created by using the DAX formula bar. Calculated columns can be used to calculate values, sums, averages, and counts within your data, while measures can only be used to calculate values. Measures are often faster and more efficient than calculated columns.
7. How can I use DAX to create dynamic reports?
Ans. DAX can be used to create dynamic reports in Power BI by using the DAX Queries functionality. This allows you to filter data by column, calculate values, and group data by column. This creates a more dynamic and interactive report experience for your users.
8. Is Dax similar to SQL?
Ans. DAX is a more simplified language that is specifically designed for data analysis. SQL is a more complex language that can be used for a variety of tasks, including database management.
9. What is the difference between Dax and Mdx?
Ans. MDX (Multi-Dimensional Expressions) is a language used for querying and managing data in multidimensional structures, such as cubes. DAX is a more simplified language that can be used for data analysis and reporting.
10. What is keepfilters in Dax?
Ans. KeepFilters is a DAX function that can be used to keep the filters from a previous query when running a new query. This allows you to easily filter data between multiple queries.
11. What are some of the most common errors made in Dax?
Ans. Some of the most common errors made in DAX include: using the wrong function, using the wrong syntax, and using the wrong arguments. It is important to be familiar with the functions and syntax of DAX in order to avoid making these errors.
12. What is the difference between dax and power query?
Ans. DAX is a language used for data analysis and reporting, while Power Query is a tool used for data extraction and transformation. Power Query can be used to combine multiple data sources into one dataset, clean up and transform data, and create calculated columns and measures.
