Data Analyst Interview Resources
Join our telegram channel to learn how data analysis can reveal fascinating patterns, trends, and stories hidden within the numbers! 📊 For ads & suggestions: @love_data
Show more📈 Analytical overview of Telegram channel Data Analyst Interview Resources
Channel Data Analyst Interview Resources (@dataanalystinterview) in the English language segment is an active participant. Currently, the community unites 52 614 subscribers, ranking 3 245 in the Education category and 6 767 in the India region.
📊 Audience metrics and dynamics
Since its creation on невідомо, the project has demonstrated rapid growth, gathering an audience of 52 614 subscribers.
According to the latest data from 27 August, 2026, the channel demonstrates stable activity. Although there has been a change in the number of participants by 60 over the last 30 days and by -8 over the last 24 hours, overall reach remains high.
- Verification status: Not verified
- Engagement rate (ER): The average audience engagement rate is 1.93%. Within the first 24 hours after publication, content typically collects 0.83% reactions from the total number of subscribers.
- Post reach: On average, each post receives 1 018 views. Within the first day, a publication typically gains 438 views.
- Reactions and interaction: The audience actively supports content: the average number of reactions per post is 2.
- Thematic interests: Content is focused on key topics such as sql, row, |--, dataset, visualization.
📝 Description and content policy
The author describes the resource as a platform for expressing subjective opinions:
“Join our telegram channel to learn how data analysis can reveal fascinating patterns, trends, and stories hidden within the numbers! 📊
For ads & suggestions: @love_data”
Thanks to the high frequency of updates (latest data received on 28 August, 2026), the channel maintains relevance and a high level of publication reach. Analytics show that the audience actively interacts with content, making it an important point of influence in the Education category.
SELECT name, salary
FROM employees;
Use cases: Retrieving specific columns, viewing datasets, extracting required information.
2️⃣ WHERE Clause (Filtering Data)
What it is: Filters rows based on specific conditions.
SELECT *
FROM orders
WHERE order_amount > 500;
Common conditions: =, >, <, >=, <=, BETWEEN, IN, LIKE
3️⃣ ORDER BY (Sorting Data)
What it is: Sorts query results in ascending or descending order.
SELECT name, salary
FROM employees
ORDER BY salary DESC;
Sorting options: ASC (default), DESC
4️⃣ GROUP BY (Aggregation)
What it is: Groups rows with same values into summary rows.
SELECT department, COUNT(*)
FROM employees
GROUP BY department;
Use cases: Sales per region, customers per country, orders per product category.
5️⃣ Aggregate Functions
What they do: Perform calculations on multiple rows.
SELECT AVG(salary)
FROM employees;
Common functions: COUNT(), SUM(), AVG(), MIN(), MAX()
6️⃣ HAVING Clause
What it is: Filters grouped data after aggregation.
SELECT department, COUNT(*)
FROM employees
GROUP BY department
HAVING COUNT(*) > 5;
Key difference: WHERE filters rows before grouping, HAVING filters groups after aggregation.
7️⃣ SQL JOINS (Combining Tables)
What they do: Combine tables.
-- INNER JOIN
SELECT orders.order_id, customers.customer_name
FROM orders
INNER JOIN customers
ON orders.customer_id = customers.customer_id;
-- LEFT JOIN
SELECT customers.customer_name, orders.order_id
FROM customers
LEFT JOIN orders
ON customers.customer_id = orders.customer_id;
Common types: INNER JOIN, LEFT JOIN, RIGHT JOIN, FULL JOIN
8️⃣ Subqueries
What it is: Query inside another query.
SELECT name
FROM employees
WHERE salary > (SELECT AVG(salary) FROM employees);
Use cases: Comparing values, filtering based on aggregated results.
9️⃣ Common Table Expressions (CTE)
What it is: Temporary result set used inside a query.
WITH high_salary AS (
SELECT name, salary
FROM employees
WHERE salary > 70000
)
SELECT *
FROM high_salary;
Benefits: Cleaner queries, easier debugging, better readability.
🔟 Window Functions
What they do: Perform calculations across rows related to current row.
SELECT name, salary, RANK() OVER (ORDER BY salary DESC) AS salary_rank
FROM employees;
Common functions: ROW_NUMBER(), RANK(), DENSE_RANK(), LAG(), LEAD()
Why SQL is Critical for Data Analysts
• Extract data from databases
• Analyze large datasets efficiently
• Generate reports and dashboards
• Support business decision-making
SQL Resources: https://whatsapp.com/channel/0029VanC5rODzgT6TiTGoa1v
Double Tap ♥️ For MoreSELECT DISTINCT column_name
FROM employees;
👉 Returns unique records but does not delete duplicates.
✅ 2️⃣ Using GROUP BY (to identify duplicates)
SELECT name, COUNT(*)
FROM employees
GROUP BY name
HAVING COUNT(*) > 1;
👉 Helps find duplicate records.
✅ 3️⃣ Delete Duplicates Using ROW_NUMBER() (Most Important ⭐)
(Keeps one record and deletes others)
DELETE FROM employees
WHERE id IN (
SELECT id FROM (
SELECT id,
ROW_NUMBER() OVER (
PARTITION BY name, salary
ORDER BY id
) AS rn
FROM employees
) t
WHERE rn > 1
);
🧠 Logic Breakdown:
- DISTINCT → shows unique records
- GROUP BY → identifies duplicates
- ROW_NUMBER() → removes duplicates safely
✅ Use Case: Data cleaning, ETL processes, data quality checks.
💡 Tip: Always take a backup before deleting duplicate records.
💬 Tap ❤️ for more!