Data Engineers
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Show more๐ Analytical overview of Telegram channel Data Engineers
Channel Data Engineers (@sql_engineer) in the English language segment is an active participant. Currently, the community unites 10 371 subscribers, ranking 19 370 in the Education category and 40 181 in the India region.
๐ Audience metrics and dynamics
Since its creation on ะฝะตะฒัะดะพะผะพ, the project has demonstrated rapid growth, gathering an audience of 10 371 subscribers.
According to the latest data from 08 June, 2026, the channel demonstrates stable activity. Although there has been a change in the number of participants by 245 over the last 30 days and by 13 over the last 24 hours, overall reach remains high.
- Verification status: Not verified
- Engagement rate (ER): The average audience engagement rate is 10.67%. Within the first 24 hours after publication, content typically collects 2.43% reactions from the total number of subscribers.
- Post reach: On average, each post receives 1 106 views. Within the first day, a publication typically gains 252 views.
- Reactions and interaction: The audience actively supports content: the average number of reactions per post is 5.
- Thematic interests: Content is focused on key topics such as sql, learning, analytic, engineer, link:-.
๐ Description and content policy
The author describes the resource as a platform for expressing subjective opinions:
โFree Data Engineering Ebooks & Coursesโ
Thanks to the high frequency of updates (latest data received on 09 June, 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 query.
Features
- Does not store data; it retrieves data from underlying tables.
- Simplifies complex queries.
Syntax
CREATE VIEW view_name AS
SELECT columns
FROM table_name
WHERE condition;
Example
Create a view to show high-salaried employees:
CREATE VIEW HighSalaryEmployees AS
SELECT name, salary
FROM employees
WHERE salary > 100000;
Use the view:
SELECT * FROM HighSalaryEmployees;
Interview Questions
1. What is the difference between a table and a view?
- A table stores data physically; a view does not.
2. Can you update data through a view?
- Yes, if the view is updatable (no joins, no aggregate functions, etc.).
3. What are the advantages of using views?
- Simplifies complex queries, enhances security, and provides abstraction. CREATE TABLE numeric_example (
id INT,
amount DECIMAL(10, 2)
);
1. String Data Types:
- CHAR, VARCHAR: For fixed and variable-length strings.
- TEXT: For large text.
- BLOB: For binary large objects like images.
- Example:
CREATE TABLE string_example (
name VARCHAR(100),
description TEXT
);
1. Date and Time Data Types:
- DATE, DATETIME, TIMESTAMP: For date and time values.
- YEAR: For storing a year.
- Example:
CREATE TABLE datetime_example (
created_at DATETIME,
year_of_joining YEAR
);
Interview Questions:
- Q1: What is the difference between CHAR and VARCHAR?
A1: CHAR has a fixed length, while VARCHAR has a variable length. VARCHAR is more storage-efficient for varying-length data.
- Q2: When should you use DECIMAL instead of FLOAT?
A2: Use DECIMAL for precise calculations (e.g., financial data) and FLOAT for approximate values where precision is less critical. INSERT INTO students (id, name, age)
VALUES (1, 'John Doe', 20);
2. Read:
Retrieving data from a table.
SELECT * FROM students;
3. Update:
Modifying existing records.
UPDATE students
SET age = 21
WHERE id = 1;
4. Delete:
Removing records.
DELETE FROM students
WHERE id = 1;
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