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El canal Data Analysis Books | Python | SQL | Excel | Artificial Intelligence | Power BI | Tableau | AI Resources (@learndataanalysis) en el segmento lingüístico de Inglés es un actor destacado. Actualmente la comunidad reúne a 53 040 suscriptores, ocupando la posición 3 214 en la categoría Educación y el puesto 6 592 en la región India.
📊 Métricas de audiencia y dinámica
Desde su creación el невідомо, el proyecto ha mostrado un crecimiento acelerado, reuniendo a 53 040 suscriptores.
Según los últimos datos del 30 agosto, 2026, el canal mantiene una actividad estable. En los últimos 30 días la variación de miembros fue de 428, y en las últimas 24 horas de 24, conservando un alto alcance.
- Estado de verificación: No verificado
- Tasa de interacción (ER): El promedio de interacción de la audiencia es 5.84%. Durante las primeras 24 horas tras publicar, el contenido suele obtener 1.18% de reacciones respecto al total de suscriptores.
- Alcance de las publicaciones: Cada publicación recibe en promedio 3 097 visualizaciones. En el primer día suele acumular 628 visualizaciones.
- Reacciones e interacción: La audiencia responde de forma activa: el promedio de reacciones por publicación es 7.
- Intereses temáticos: El contenido se centra en temas clave como analyst, |--, excel, visualization, analytic.
📝 Descripción y política de contenido
El autor describe el recurso como un espacio para expresar opiniones subjetivas:
“Data Analysis Useful Resources
#dataanalysis
#dataanalysisbooks
#sqlbooks
#pythonbooks
#tableau
#powerbi
#datavisualization
For promotions: @coderfun”
Gracias a la alta frecuencia de actualizaciones (últimos datos recibidos el 31 agosto, 2026), el canal mantiene la vigencia y un amplio alcance. La analítica demuestra que la audiencia interactúa activamente con el contenido, lo que lo convierte en un punto de referencia dentro de la categoría Educación.
GFGWINTERARC for 25% OFF (Limited Time!).dropna(), .fillna() functions to do this easily.
4. What are list comprehensions and how are they useful?
Concise syntax to create lists from iterables using a single readable line, often replacing loops for cleaner and faster code.
Example: [x**2 for x in range(5)] → ``
5. Explain Pandas DataFrame and Series.
⦁ Series: 1D labeled array, like a column.
⦁ DataFrame: 2D labeled data structure with rows and columns, like a spreadsheet.
6. How do you read data from different file formats (CSV, Excel, JSON) in Python?
Using Pandas:
⦁ CSV: pd.read_csv('file.csv')
⦁ Excel: pd.read_excel('file.xlsx')
⦁ JSON: pd.read_json('file.json')
7. What is the difference between Python’s append() and extend() methods?
⦁ append() adds its argument as a single element to the end of a list.
⦁ extend() iterates over its argument adding each element to the list.
8. How do you filter rows in a Pandas DataFrame?
Using boolean indexing:
df[df['column'] > value] filters rows where ‘column’ is greater than value.
9. Explain the use of groupby() in Pandas with an example.
groupby() splits data into groups based on column(s), then you can apply aggregation.
Example: df.groupby('category')['sales'].sum() gives total sales per category.
10. What are lambda functions and how are they used?
Anonymous, inline functions defined with lambda keyword. Used for quick, throwaway functions without formally defining with def.
Example: df['new'] = df['col'].apply(lambda x: x*2)
React ♥️ for Part 2SELECT department, AVG(salary)
FROM employees
WHERE salary > 3000
GROUP BY department
HAVING AVG(salary) > 5000;
2. Write a query to find the second-highest salary.
Solution:
SELECT MAX(salary) AS second_highest_salary
FROM employees
WHERE salary < (SELECT MAX(salary) FROM employees);
3. How do you fetch the first 5 rows of a table?
Solution:
SELECT * FROM employees
LIMIT 5; -- (MySQL/PostgreSQL)
For SQL Server:
SELECT TOP 5 * FROM employees;
4. Write a query to find duplicate records in a table.
Solution:
SELECT column1, column2, COUNT(*)
FROM table_name
GROUP BY column1, column2
HAVING COUNT(*) > 1;
5. How do you find employees who don’t belong to any department?
Solution:
SELECT *
FROM employees
WHERE department_id IS NULL;
6. What is a JOIN, and write a query to fetch data using INNER JOIN.
Solution:
A JOIN combines rows from two or more tables based on a related column.
SELECT e.name, d.department_name
FROM employees e
INNER JOIN departments d ON e.department_id = d.id;
7. Write a query to find the total number of employees in each department.
Solution:
SELECT department_id, COUNT(*) AS total_employees
FROM employees
GROUP BY department_id;
8. How do you fetch the current date in SQL?
Solution:
SELECT CURRENT_DATE; -- MySQL/PostgreSQL
SELECT GETDATE(); -- SQL Server
9. Write a query to delete duplicate rows but keep one.
Solution:
WITH CTE AS (
SELECT *, ROW_NUMBER() OVER (PARTITION BY column1, column2 ORDER BY id) AS rn
FROM table_name
)
DELETE FROM CTE WHERE rn > 1;
10. What is a Common Table Expression (CTE), and how do you use it?
Solution:
A CTE is a temporary result set defined within a query.
WITH EmployeeCTE AS (
SELECT department_id, COUNT(*) AS total_employees
FROM employees
GROUP BY department_id
)
SELECT * FROM EmployeeCTE WHERE total_employees > 10;
Hope it helps :)
#sql #dataanalysts