Data Analyst Interview Resources
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نمایش بیشتر📈 تحلیل کانال تلگرام Data Analyst Interview Resources
کانال Data Analyst Interview Resources (@dataanalystinterview) در بخش زبانی انگلیسی بازیگری فعال است. در حال حاضر جامعه شامل 52 310 مشترک است و جایگاه 3 374 را در دسته آموزش و رتبه 6 625 را در منطقه الهند دارد.
📊 شاخصهای مخاطب و پویایی
از زمان ایجاد در невідомо، پروژه رشد سریعی داشته و 52 310 مشترک جذب کرده است.
بر اساس آخرین دادهها در تاریخ 29 اکتبر, 2026، کانال فعالیت پایداری دارد. در ۳۰ روز گذشته تغییر اعضا برابر -246 و در ۲۴ ساعت گذشته برابر -1 بوده و همچنان دسترسی گستردهای حفظ شده است.
- وضعیت تأیید: تأیید نشده
- نرخ تعامل (ER): میانگین تعامل مخاطب 2.36% است و در ۲۴ ساعت نخست پس از انتشار، محتوا معمولاً 0.73% واکنش نسبت به کل مشترکان کسب میکند.
- دسترسی پستها: هر پست به طور میانگین 1 236 بازدید دریافت میکند. در اولین روز معمولاً 383 بازدید جمعآوری میشود.
- واکنشها و تعامل: مخاطبان بهطور فعال حمایت میکنند؛ میانگین واکنش به هر پست 4 است.
- علایق موضوعی: محتوا بر موضوعات کلیدی مانند sql, row, |--, dataset, visualization تمرکز دارد.
📝 توضیح و سیاست محتوایی
نویسنده این فضا را محل بیان دیدگاههای شخصی توصیف میکند:
“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”
به لطف بهروزرسانیهای پرتکرار (آخرین داده در تاریخ 30 اکتبر, 2026)، کانال همواره بهروز و دارای دسترسی بالاست. تحلیلها نشان میدهد مخاطبان بهطور فعال با محتوا تعامل دارند و آن را به نقطه اثرگذاری مهم در دسته آموزش تبدیل کردهاند.
SELECT department_id, AVG(salary) AS avg_salary
FROM employees
GROUP BY department_id;
2. What does Filter context in DAX mean?
Answer - Filter context in DAX refers to the subset of data that is actively being used in the calculation of a measure or in the evaluation of an expression. This context is determined by filters on the dashboard items like slicers, visuals, and filters pane which restrict the data being processed.
3. Explain how to implement Row-Level Security (RLS) in Power BI.
Answer - Row-Level Security (RLS) in Power BI can be implemented by:
- Creating roles within the Power BI service.
- Defining DAX expressions that specify the data each role can access.
- Assigning users to these roles either in Power BI or dynamically through AD group membership.
4. Create a dictionary, add elements to it, modify an element, and then print the dictionary in alphabetical order of keys.
Answer -
d = {'apple': 2, 'banana': 5}
d['orange'] = 3 # Add element
d['apple'] = 4 # Modify element
sorted_d = dict(sorted(d.items())) # Sort dictionary
print(sorted_d)
5. Find and print duplicate values in a list of assorted numbers, along with the number of times each value is repeated.
Answer -
from collections import Counter
numbers = [1, 2, 2, 3, 4, 5, 1, 6, 7, 3, 8, 1]
count = Counter(numbers)
duplicates = {k: v for k, v in count.items() if v > 1}
print(duplicates)
Like ❤️ & Share the post if you want me to post more similar content. 😊WITH RECURSIVE EmployeeHierarchy AS (
SELECT employee_id, employee_name, manager_id
FROM employees
WHERE manager_id IS NULL
UNION ALL
SELECT e.employee_id, e.employee_name, e.manager_id
FROM employees e
JOIN EmployeeHierarchy eh ON e.manager_id = eh.employee_id
)
SELECT *
FROM EmployeeHierarchy;
2. Pivoting Data
Turn row data into columns (e.g., show product categories as separate columns).
SELECT *
FROM (
SELECT TO_CHAR(order_date, 'YYYY-MM') AS month, product_category, sales_amount
FROM sales
) AS pivot_data
PIVOT (
SUM(sales_amount)
FOR product_category IN ('Electronics', 'Clothing', 'Books')
) AS pivoted_sales;
3. Window Functions
Calculate a running total of sales based on order date.
SELECT
order_date,
sales_amount,
SUM(sales_amount) OVER (ORDER BY order_date) AS running_total
FROM sales;
4. Ranking with Window Functions
Rank employees’ salaries within each department.
SELECT
department,
employee_name,
salary,
RANK() OVER (PARTITION BY department ORDER BY salary DESC) AS salary_rank
FROM employees;
5. Finding Gaps in Sequences
Identify missing values in a sequential dataset (e.g., order numbers).
WITH Sequences AS (
SELECT MIN(order_number) AS start_seq, MAX(order_number) AS end_seq
FROM orders
)
SELECT start_seq + 1 AS missing_sequence
FROM Sequences
WHERE NOT EXISTS (
SELECT 1
FROM orders o
WHERE o.order_number = Sequences.start_seq + 1
);
6. Unpivoting Data
Convert columns into rows to simplify analysis of multiple attributes.
SELECT
product_id,
attribute_name,
attribute_value
FROM products
UNPIVOT (
attribute_value FOR attribute_name IN (color, size, weight)
) AS unpivoted_data;
7. Finding Consecutive Events
Check for consecutive days/orders for the same product using LAG().
WITH ConsecutiveOrders AS (
SELECT
product_id,
order_date,
LAG(order_date) OVER (PARTITION BY product_id ORDER BY order_date) AS prev_order_date
FROM orders
)
SELECT product_id, order_date, prev_order_date
FROM ConsecutiveOrders
WHERE order_date - prev_order_date = 1;
8. Aggregation with the FILTER Clause
Calculate selective averages (e.g., only for the Sales department).
SELECT
department,
AVG(salary) FILTER (WHERE department = 'Sales') AS avg_salary_sales
FROM employees
GROUP BY department;
9. JSON Data Extraction
Extract values from JSON columns directly in SQL.
SELECT
order_id,
customer_id,
order_details ->> 'product' AS product_name,
CAST(order_details ->> 'quantity' AS INTEGER) AS quantity
FROM orders;
10. Using Temporary Tables
Create a temporary table for intermediate results, then join it with other tables.
-- Create a temporary table
CREATE TEMPORARY TABLE temp_product_sales AS
SELECT product_id, SUM(sales_amount) AS total_sales
FROM sales
GROUP BY product_id;
-- Use the temp table
SELECT p.product_name, t.total_sales
FROM products p
JOIN temp_product_sales t ON p.product_id = t.product_id;
Why These Matter
Advanced SQL queries let you handle complex data manipulation and analysis tasks with ease. From traversing hierarchical relationships to reshaping data (pivot/unpivot) and working with JSON, these techniques expand your ability to derive insights from relational databases.
Keep practicing these queries to solidify your SQL expertise and make more data-driven decisions!
Here you can find essential SQL Interview Resources👇
https://whatsapp.com/channel/0029VanC5rODzgT6TiTGoa1v
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Hope it helps :)
#sql #dataanalyst