Tuesday, 21 January 2025

Top 5 Questions About Learning Data Science Courses in Kolkata Answered


 


What is Data Science?

Data Science involves the extraction of data from varied sources using programming and tools, transformation of the data and analysis of business information into user understandable format.

Enroll in the best data science course in Kolkata! The requirement for candidate with data science skills is increasing  all over the world and particularly in India. This is the right time for individuals to upskill themselves and get into this growing domain. Several institutes offer data science courses – big and small and it can be quite difficult to identify the right course to take.

Therefore, we have provided a list of frequently asked questions and their answers in this article so that you can make the decision.

FAQs- The Best Data Science Course In Kolkata:

1. What are the career prospects after completing a data science course?

The data science field offers many exciting career opportunities, as discussed below:

Data Analyst: Data analysts will be mostly responsible for gathering, cleaning, and analyzing data to generate insight. It is their responsibility to regularly work with stakeholders to help turn these things into tangible recommendations.

Data Scientist: Data scientists build and deploy machine learning models to solve certain problems. Many of them have skills in programming languages and are well acquainted with different statistical methods.

Business Analyst: Depending on their nature, they might help refine your business acumen. It will be useful to businesses to predict the behavior of consumers, optimize marketing campaigns, and identify important trends.  

Machine Learning Engineer: These experts create, build, and release machine learning models into the field as tools for recommendation systems for fraud detection.

Data Science Consultant: They deliver bespoke data science solutions to clients within particular subject areas

These are just a few examples you can choose after this course, depending on your interests.

2. What are the prerequisites for joining a data science course in Kolkata?

This depends on the involved institutes and the level of the program offered, basic, intermediate, or advanced.

Math skills: Linear algebra, calculus, and statistics are mandatory to learn to comprehend the ideas behind data science.

Programming proficiency: A minimum level of knowledge about problem-oriented languages such as Python is required.

SQL knowledge: You should be able to write simple SQL queries that allow for extraction from databases.

Analytical thinking: You should have the ability to analyze data critically, identify patterns, and draw meaningful conclusions.

3. What factors should I consider when choosing the best data science course in Kolkata?

Course curriculum: Ensure that this course comprises elements like; data management, data analysis, machine learning, and data presentation.

Faculty expertise:  Look for experts who have experience in data science environments. They can provide useful input and advice to you.

Course format:  The data science courses may also be attained as full courses, part-time, or as online and classroom courses. Select the one that should match your schedule and the way you learn.

Project opportunities: Search for classes that provide projects that you can use in real-world scenarios.

Placement assistance: Inquire if an institute provides career assistance or placement support.

Cost: To get the right one is not a big deal. This depends on your budget.

4. What is the average cost of a data science course in Kolkata?

It can be between ₹20,000 and ₹50,000. This depends on factors like mode of delivery, number of students in a class – less the better, the period of the course, the repute of the institute, or the extent to which industry is integrated with experienced faculty. .

5. How can I find the best data science course in Kolkata?

Explore online platforms like Google, LinkedIn, and social media groups. Study feedback from the candidates who have already taken the classes.

Some of the institutes organize information sessions and workshops. Go to these events to find out more.

If possible, speak with the institute, make visits to the centers/campuses of the institutes, which have been shortlisted.

Enroll in the best data science course in Kolkata at https://www.paliumskills.com/! This course will give you insights into applying data and analytics principles in your business. View the link to get more information about the course: https://paliumskills.com/courses/data-analyst/

Sunday, 5 January 2025

Power BI Certification (PL-300) Questions & Answer Pattern


🧠 Power BI Certification (PL-300) Questions & Answer

1. Prepare the Data (15–20%)

No. Question Answer Explanation
1 Which Power Query feature allows you to detect null values or outliers? Column Profiling / Data Profiling The Data Profiling feature in Power Query (Column quality, distribution, profile) identifies missing or abnormal values.
2 Difference between “Import” and “DirectQuery” mode? Import stores data; DirectQuery reads live data Import caches data inside the model; DirectQuery queries the source every time—good for real-time, but slower.
3 How to handle changing column names in a data source? Use column headers by position or rename columns manually Prevent refresh errors by renaming columns in Power Query to fixed names or using “Transform → Rename Columns.”
4 What does the “Enable Load” option in Power Query do? Controls if query appears in the model Disable load for intermediate queries to improve performance and reduce model size.
5 When should you use parameters in Power Query? For dynamic inputs such as file paths, dates, or filters Parameters allow reusability and automation for different environments (Dev/Test/Prod).

2. Model the Data (30–35%)

No. Question Answer Explanation
6 What type of relationship is created when both fields have unique values? One-to-one relationship Both tables have unique keys—rare but sometimes needed for lookups.
7 Difference between calculated column and measure? Column is row-level; measure is aggregated at query time Columns are stored in model, increasing size; measures are computed dynamically for better performance.
8 Function of RELATED() DAX function? Fetches a value from a related table It follows a relationship to bring related column values into current context.
9 How do you create a hierarchy in Power BI? Drag fields (e.g., Year → Quarter → Month → Day) into hierarchy Used for drill-down analysis in visuals.
10 Star vs. snowflake schema? Star: single-level dimension; Snowflake: normalized dimensions Star schema improves performance and is recommended for Power BI.
11 Purpose of Row-Level Security (RLS)? Restricts data access per user Filters the model data so each user sees only their allowed subset.
12 DAX function to calculate year-to-date values? TOTALYTD() Calculates cumulative total from beginning of year to current date.
13 How does Power BI handle circular relationships? It prevents them and prompts an error You must remove one link or redesign model to avoid ambiguity.
14 Effect of “Cross Filter Direction = Both”? Filters flow in both directions Useful in many-to-many relationships but can cause ambiguity if overused.
15 Difference between SUMX() and SUM()? SUMX iterates row-by-row; SUM aggregates one column SUMX = table expression + expression evaluation; SUM = simple column sum.

3. Visualize and Analyze the Data (25–30%)

No. Question Answer Explanation
16 Purpose of slicer? Interactive filtering for visuals Allows end users to dynamically filter report content.
17 How to sync slicers across pages? Use “Sync Slicers” pane Lets you control slicer visibility and synchronization across pages.
18 Which visual best shows trend over time? Line chart Ideal for time-series data to show progression or trends.
19 What are drillthrough pages used for? Detailed analysis of a selected data point Allows focusing on one item from a summary visual.
20 Difference between filter, slicer, and visual-level filter? Scope: report, page, or visual Filter pane = global or page-specific; slicer = user-interactive; visual-level = affects one chart.
21 How to add conditional formatting? Use “Format → Conditional Formatting” on fields Change color, data bars, icons based on measure values.
22 Use of “Analyze” feature (“Explain the Increase”)? AI-driven analysis of variance in visuals Helps identify causes for change in a measure automatically.
23 Role of bookmarks and buttons? Create interactive storytelling/navigation Bookmarks save visual states; buttons trigger them for user experience.
24 How to customize tooltip information? Use “Report Page Tooltips Create a mini report page and assign as tooltip to visuals.
25 How to show KPIs in Power BI? Use KPI visual or card visuals with targets Compare actual vs target performance metrics.

4. Deploy and Maintain Assets (20–25%)

No. Question Answer Explanation
26 Difference between a workspace and an app? Workspace = build area; App = published package Apps share finalized content securely with users.
27 How to schedule dataset refreshes? In Power BI Service → Dataset Settings → Schedule Refresh Automates data updates at defined intervals.
28 What are gateways used for? To connect on-premises data to Power BI cloud Required for refresh and DirectQuery to local sources.
29 How to share reports securely? Publish to workspace → share via app or permissions Manage access with Azure AD or distribution groups.
30 How to monitor dataset refresh failures? Use refresh history or Power BI admin portal alerts Provides error logs for troubleshooting.
31 Permissions required to publish to a workspace? Contributor or higher Roles: Viewer, Contributor, Member, Admin.
32 Role of sensitivity labels? Classify and protect confidential data Integrates with Microsoft Purview for data governance.
33 Deploy dataset from dev to prod workspace? Use Deployment Pipelines Promotes content across development, test, production stages.
34 Purpose of Power BI Dataflows? Reusable ETL processes in cloud Built using Power Query online for multiple reports.
35 How to monitor performance? Use Performance Analyzer Captures DAX query times and visual rendering time.

5. Advanced and Scenario-Based

No. Question Answer Explanation
36 Need real-time updates — which connection mode? Streaming dataset or DirectQuery Streaming = push data in real-time; DirectQuery = live connection.
37 Report is slow to load — first step? Check model size and visuals using Performance Analyzer Identify whether bottleneck is DAX, visuals, or query.
38 DAX for rolling 12-month average? AVERAGEX(DATESINPERIOD(...)) Uses DATESINPERIOD with CALCULATE/AVERAGEX for moving averages.
39 Difference between Import, DirectQuery, Live Connection? Import = cached; DirectQuery = source queried; Live = external model Live connection is for Analysis Services or Power BI datasets.
40 Implement dynamic RLS? Use USERPRINCIPALNAME() or USERNAME() in DAX Filters data dynamically per logged-in user.
41 Benefit of composite models? Combine Import + DirectQuery Offers flexibility in performance and data freshness.
42 What are deployment pipelines? Dev–Test–Prod workflow automation Ensures version control and governed release management.
43 Reduce dataset size? Remove unused columns, use proper data types, aggregate tables Optimizes memory and refresh time.
44 Visual to compare performance across categories? Bar or column chart Ideal for comparing values among discrete categories.
45 Refresh data every 15 minutes — how? Use Power BI Premium or push dataset Standard Power BI Pro allows 8 refreshes/day; Premium allows 48.

6. Case Study-Style Questions

No. Scenario Recommended Solution
46 Track sales by region and category with drilldown Use star schema, build hierarchies, and use matrix or treemap visuals with drilldown.
47 Dataset grows daily, causing slow refresh Use incremental refresh with date range filters and partitioned refresh policies.
48 Need to share with external users Use Power BI App + Azure B2B guest access or Publish to web (non-secure) depending on sensitivity.
49 Managers should see only their team data Implement dynamic RLS with USERPRINCIPALNAME() and mapping table of managers–teams.
50 Publish a dashboard with auto-updates Use DirectQuery or streaming dataset + scheduled refresh in service + pin visuals to dashboard.
 

📘 Summary of Key Exam Facts

Item Details
Exam Code PL-300: Microsoft Power BI Data Analyst
Type Multiple choice + scenario questions
Passing Score 700 / 1000
Duration 100–120 mins
Languages English, Japanese, etc.
Official Learning Path Microsoft Learn – PL-300
 

🏆 How Palium Skills Helps You Succeed

Palium Skills provides hands-on Power BI training aligned with PL-300 certification objectives:

✅ Expert-led live sessions
✅ Case studies using real corporate datasets
DAX practice sets & mock exams
✅ Guidance for career paths in Data Analytics

📍Contact: +91 8420594969 / 7044871915
🌐 Website: www.paliumskills.com