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
Ko'proq ko'rsatish📈 Telegram kanali Data Analyst Interview Resources analitikasi
Data Analyst Interview Resources (@dataanalystinterview) Ingliz til segmentidagi kanali faol ishtirokchi. Hozirda hamjamiyat 52 614 obunachidan iborat bo'lib, Taʼlim toifasida 3 245-o'rinni va Hindiston mintaqasida 6 767-o'rinni egallagan.
📊 Auditoriya ko‘rsatkichlari va dinamika
невідомо sanasidan buyon loyiha tez o‘sib, 52 614 obunachiga ega bo‘ldi.
27 Avgust, 2026 dagi oxirgi ma’lumotlarga ko‘ra kanal barqaror faollikka ega. Oxirgi 30 kunda obunachilar soni 60 ga, so‘nggi 24 soatda esa -8 ga o‘zgardi va umumiy qamrov yuqori darajada qolmoqda.
- Tasdiqlash holati: Tasdiqlanmagan
- Jalb etish (ER): Auditoriya o‘rtacha 1.93% darajada jalb etiladi. Nashrdan keyingi dastlabki 24 soatda kontent odatda umumiy obunachilar sonining 0.83% ini tashkil etuvchi reaksiyalarni to‘playdi.
- Post qamrovi: Har bir post o‘rtacha 1 018 marta ko‘riladi; birinchi sutkada odatda 438 ta ko‘rish yig‘iladi.
- Reaksiyalar va o‘zaro ta’sir: Auditoriya faol: har bir postga o‘rtacha 2 ta reaksiya keladi.
- Tematik yo‘nalishlar: Kontent sql, row, |--, dataset, visualization kabi asosiy mavzularga jamlangan.
📝 Tavsif va kontent siyosati
Muallif resursni shaxsiy fikrni ifoda etish maydoni sifatida ta’riflaydi:
“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”
Yuqori yangilanish chastotasi (oxirgi ma’lumot 28 Avgust, 2026 da olingan) sababli kanal doimo dolzarb va katta qamrovli bo‘lib qoladi. Analitika auditoriya kontent bilan faol hamkorlik qilishini, uni Taʼlim toifasidagi muhim ta’sir nuqtasiga aylantirishini ko‘rsatadi.
GROUP BY clause with COUNT(*) to aggregate employee counts per department.
🔹 Query:
SELECT department, COUNT(*) AS employee_count
FROM employees
GROUP BY department;
✔ Why it works:
– GROUP BY groups rows by department
– COUNT(*) counts employees in each group
– Clean, scalable, and works with large datasets
🔎 Bonus Insight:
To filter only departments with more than 5 employees:
SELECT department, COUNT(*) AS employee_count
FROM employees
GROUP BY department
HAVING COUNT(*) > 5;
– HAVING filters aggregated results
– Useful in dashboards, reports, and business logic
💬 Tap ❤️ for more SQL interview tips!SELECT MAX(salary)
FROM employees
WHERE salary < (SELECT MAX(salary) FROM employees);
6. Explain INNER JOIN vs LEFT JOIN with examples.
⦁ INNER JOIN: Returns only matching rows between two tables.
⦁ LEFT JOIN: Returns all rows from the left table, plus matching rows from the right; if no match, right columns are NULL.
Example:
SELECT * FROM A INNER JOIN B ON A.id = B.id;
SELECT * FROM A LEFT JOIN B ON A.id = B.id;
7. What are outliers? How do you detect and treat them?
⦁ Outliers are data points significantly different from others that can skew analysis.
⦁ Detect with boxplots, z-score (>3), or IQR method (values outside 1.5*IQR).
⦁ Treat by investigating causes, correcting errors, transforming data, or removing if they’re noise.
8. Describe what a pivot table is and how you use it.
A pivot table is a data summarization tool that groups, aggregates (sum, average), and displays data cross-categorically. Used in Excel and BI tools for quick insights and reporting.
9. How do you validate a data model’s performance?
⦁ Use relevant metrics (accuracy, precision, recall for classification; RMSE, MAE for regression).
⦁ Perform cross-validation to check generalizability.
⦁ Test on holdout or unseen data sets.
10. What is hypothesis testing? Explain t-test and z-test.
⦁ Hypothesis testing assesses if sample data supports a claim about a population.
⦁ t-test: Used when sample size is small and population variance is unknown, often comparing means.
⦁ z-test: Used for large samples with known variance to test population parameters.
React ♥️ for Part-2