How you can learn Data Analytics in 28 days:
Week 1: Excel
• Learn functions (VLOOKUP, Pivot Tables)
• Clean and format data
• Analyze trends
Week 2: SQL
• Learn SELECT, WHERE, JOIN
• Query real datasets
• Aggregate and filter data
Week 3: Power BI/Tableau
• Build dashboards
• Create data visualizations
• Tell stories with data
Week 4: Real-World Project
• Analyze a data
• Share insights
• Build a portfolio
One skill at a time → Real progress in a month! Start today
Week 1: Excel
• Learn functions (VLOOKUP, Pivot Tables)
• Clean and format data
• Analyze trends
Week 2: SQL
• Learn SELECT, WHERE, JOIN
• Query real datasets
• Aggregate and filter data
Week 3: Power BI/Tableau
• Build dashboards
• Create data visualizations
• Tell stories with data
Week 4: Real-World Project
• Analyze a data
• Share insights
• Build a portfolio
One skill at a time → Real progress in a month! Start today
❤18👍2
Hey guys,
Today, let’s talk about SQL conceptual questions that are often asked in data analyst interviews. These questions test not only your technical skills but also your conceptual understanding of SQL and its real-world applications.
1. What is the difference between SQL and NoSQL?
- SQL (Structured Query Language) is a relational database management system, meaning it uses tables (rows and columns) to store data.
- NoSQL databases, on the other hand, handle unstructured data and don’t rely on a schema, making them more flexible in terms of data storage and retrieval.
- Interview Tip: Don't just memorize definitions. Be prepared to explain scenarios where you’d use SQL over NoSQL, and vice versa.
2. What is the difference between INNER JOIN and OUTER JOIN?
- An INNER JOIN returns records that have matching values in both tables.
- An OUTER JOIN returns all records from one table and the matched records from the second table. If there's no match, NULL values are returned.
3. How do you optimize a SQL query for better performance?
- Indexing: Create indexes on columns used frequently in WHERE, JOIN, or GROUP BY clauses.
- Query optimization: Use appropriate WHERE clauses to reduce the data set and avoid unnecessary calculations.
- Avoid SELECT *: Always specify the columns you need to reduce the amount of data retrieved.
- Limit results: If you only need a subset of the data, use the LIMIT clause.
4. What are the different types of SQL constraints?
Constraints are used to enforce rules on data in a table. They ensure the accuracy and reliability of the data. The most common types are:
- PRIMARY KEY: Ensures each record is unique and not null.
- FOREIGN KEY: Enforces a relationship between two tables.
- UNIQUE: Ensures all values in a column are unique.
- NOT NULL: Prevents NULL values from being entered into a column.
- CHECK: Ensures a column's values meet a specific condition.
5. What is normalization? What are the different normal forms?
Normalization is the process of organizing data to reduce redundancy and improve data integrity. Here’s a quick overview of normal forms:
- 1NF (First Normal Form): Ensures that all values in a table are atomic (indivisible).
- 2NF (Second Normal Form): Ensures that the table is in 1NF and that all non-key columns are fully dependent on the primary key.
- 3NF (Third Normal Form): Ensures that the table is in 2NF and all columns are independent of each other except for the primary key.
6. What is a subquery?
A subquery is a query within another query. It's used to perform operations that need intermediate results before generating the final query.
Example:
In this case, the subquery calculates the average salary, and the outer query selects employees whose salary is greater than the average.
7. What is the difference between a UNION and a UNION ALL?
- UNION combines the result sets of two SELECT statements and removes duplicates.
- UNION ALL combines the result sets and includes duplicates.
8. What is the difference between WHERE and HAVING clause?
- WHERE filters rows before any groupings are made. It’s used with SELECT, INSERT, UPDATE, or DELETE statements.
- HAVING filters groups after the GROUP BY clause.
9. How would you handle NULL values in SQL?
NULL values can represent missing or unknown data. Here’s how to manage them:
- Use IS NULL or IS NOT NULL in WHERE clauses to filter null values.
- Use COALESCE() or IFNULL() to replace NULL values with default ones.
Example:
10. What is the purpose of the GROUP BY clause?
The GROUP BY clause groups rows with the same values into summary rows. It’s often used with aggregate functions like COUNT, SUM, AVG, etc.
Example:
Here you can find SQL Interview Resources👇
https://news.1rj.ru/str/DataSimplifier
Share with credits: https://news.1rj.ru/str/sqlspecialist
Hope it helps :)
Today, let’s talk about SQL conceptual questions that are often asked in data analyst interviews. These questions test not only your technical skills but also your conceptual understanding of SQL and its real-world applications.
1. What is the difference between SQL and NoSQL?
- SQL (Structured Query Language) is a relational database management system, meaning it uses tables (rows and columns) to store data.
- NoSQL databases, on the other hand, handle unstructured data and don’t rely on a schema, making them more flexible in terms of data storage and retrieval.
- Interview Tip: Don't just memorize definitions. Be prepared to explain scenarios where you’d use SQL over NoSQL, and vice versa.
2. What is the difference between INNER JOIN and OUTER JOIN?
- An INNER JOIN returns records that have matching values in both tables.
- An OUTER JOIN returns all records from one table and the matched records from the second table. If there's no match, NULL values are returned.
3. How do you optimize a SQL query for better performance?
- Indexing: Create indexes on columns used frequently in WHERE, JOIN, or GROUP BY clauses.
- Query optimization: Use appropriate WHERE clauses to reduce the data set and avoid unnecessary calculations.
- Avoid SELECT *: Always specify the columns you need to reduce the amount of data retrieved.
- Limit results: If you only need a subset of the data, use the LIMIT clause.
4. What are the different types of SQL constraints?
Constraints are used to enforce rules on data in a table. They ensure the accuracy and reliability of the data. The most common types are:
- PRIMARY KEY: Ensures each record is unique and not null.
- FOREIGN KEY: Enforces a relationship between two tables.
- UNIQUE: Ensures all values in a column are unique.
- NOT NULL: Prevents NULL values from being entered into a column.
- CHECK: Ensures a column's values meet a specific condition.
5. What is normalization? What are the different normal forms?
Normalization is the process of organizing data to reduce redundancy and improve data integrity. Here’s a quick overview of normal forms:
- 1NF (First Normal Form): Ensures that all values in a table are atomic (indivisible).
- 2NF (Second Normal Form): Ensures that the table is in 1NF and that all non-key columns are fully dependent on the primary key.
- 3NF (Third Normal Form): Ensures that the table is in 2NF and all columns are independent of each other except for the primary key.
6. What is a subquery?
A subquery is a query within another query. It's used to perform operations that need intermediate results before generating the final query.
Example:
SELECT employee_id, name
FROM employees
WHERE salary > (SELECT AVG(salary) FROM employees);
In this case, the subquery calculates the average salary, and the outer query selects employees whose salary is greater than the average.
7. What is the difference between a UNION and a UNION ALL?
- UNION combines the result sets of two SELECT statements and removes duplicates.
- UNION ALL combines the result sets and includes duplicates.
8. What is the difference between WHERE and HAVING clause?
- WHERE filters rows before any groupings are made. It’s used with SELECT, INSERT, UPDATE, or DELETE statements.
- HAVING filters groups after the GROUP BY clause.
9. How would you handle NULL values in SQL?
NULL values can represent missing or unknown data. Here’s how to manage them:
- Use IS NULL or IS NOT NULL in WHERE clauses to filter null values.
- Use COALESCE() or IFNULL() to replace NULL values with default ones.
Example:
SELECT name, COALESCE(age, 0) AS age
FROM employees;
10. What is the purpose of the GROUP BY clause?
The GROUP BY clause groups rows with the same values into summary rows. It’s often used with aggregate functions like COUNT, SUM, AVG, etc.
Example:
SELECT department, COUNT(*)
FROM employees
GROUP BY department;
Here you can find SQL Interview Resources👇
https://news.1rj.ru/str/DataSimplifier
Share with credits: https://news.1rj.ru/str/sqlspecialist
Hope it helps :)
❤11
Everyone thinks being a great data analyst is about advanced algorithms and complex dashboards.
But real data excellence comes from methodical habits that build trust and deliver real insights.
Here are 20 signs of a truly effective analyst 👇
✅ They document every step of their analysis
➝ Clear notes make their work reproducible and trustworthy.
✅ They check data quality before the analysis begins
➝ Garbage in = garbage out. Always validate first.
✅ They use version control religiously
➝ Every code change is tracked. Nothing gets lost.
✅ They explore data thoroughly before diving in
➝ Understanding context prevents costly misinterpretations.
✅ They create automated noscripts for repetitive tasks
➝ Efficiency isn’t a luxury—it’s a necessity.
✅ They maintain a reusable code library
➝ Smart analysts never solve the same problem twice.
✅ They test assumptions with multiple validation methods
➝ One test isn’t enough; they triangulate confidence.
✅ They organize project files logically
➝ Their work is navigable by anyone, not just themselves.
✅ They seek peer reviews on critical work
➝ Fresh eyes catch blind spots.
✅ They continuously absorb industry knowledge
➝ Learning never stops. Trends change too quickly.
✅ They prioritize business-impacting projects
➝ Every analysis must drive real decisions.
✅ They explain complex findings simply
➝ Technical brilliance is useless without clarity.
✅ They write readable, well-commented code
➝ Their work is accessible to others, long after they're gone.
✅ They maintain robust backup systems
➝ Data loss is never an option.
✅ They learn from analytical mistakes
➝ Errors become stepping stones, not roadblocks.
✅ They build strong stakeholder relationships
➝ Data is only valuable when people use it.
✅ They break complex projects into manageable chunks
➝ Progress happens through disciplined, incremental work.
✅ They handle sensitive data with proper security
➝ Compliance isn’t optional—it’s foundational.
✅ They create visualizations that tell clear stories
➝ A chart without a narrative is just decoration.
✅ They actively seek evidence against their conclusions
➝ Confirmation bias is their biggest enemy.
The best analysts aren’t the ones with the most tools—they’re the ones with the most rigorous practices.
But real data excellence comes from methodical habits that build trust and deliver real insights.
Here are 20 signs of a truly effective analyst 👇
✅ They document every step of their analysis
➝ Clear notes make their work reproducible and trustworthy.
✅ They check data quality before the analysis begins
➝ Garbage in = garbage out. Always validate first.
✅ They use version control religiously
➝ Every code change is tracked. Nothing gets lost.
✅ They explore data thoroughly before diving in
➝ Understanding context prevents costly misinterpretations.
✅ They create automated noscripts for repetitive tasks
➝ Efficiency isn’t a luxury—it’s a necessity.
✅ They maintain a reusable code library
➝ Smart analysts never solve the same problem twice.
✅ They test assumptions with multiple validation methods
➝ One test isn’t enough; they triangulate confidence.
✅ They organize project files logically
➝ Their work is navigable by anyone, not just themselves.
✅ They seek peer reviews on critical work
➝ Fresh eyes catch blind spots.
✅ They continuously absorb industry knowledge
➝ Learning never stops. Trends change too quickly.
✅ They prioritize business-impacting projects
➝ Every analysis must drive real decisions.
✅ They explain complex findings simply
➝ Technical brilliance is useless without clarity.
✅ They write readable, well-commented code
➝ Their work is accessible to others, long after they're gone.
✅ They maintain robust backup systems
➝ Data loss is never an option.
✅ They learn from analytical mistakes
➝ Errors become stepping stones, not roadblocks.
✅ They build strong stakeholder relationships
➝ Data is only valuable when people use it.
✅ They break complex projects into manageable chunks
➝ Progress happens through disciplined, incremental work.
✅ They handle sensitive data with proper security
➝ Compliance isn’t optional—it’s foundational.
✅ They create visualizations that tell clear stories
➝ A chart without a narrative is just decoration.
✅ They actively seek evidence against their conclusions
➝ Confirmation bias is their biggest enemy.
The best analysts aren’t the ones with the most tools—they’re the ones with the most rigorous practices.
❤8
Hey guys,
Today, let’s talk about SQL conceptual questions that are often asked in data analyst interviews. These questions test not only your technical skills but also your conceptual understanding of SQL and its real-world applications.
1. What is the difference between SQL and NoSQL?
- SQL (Structured Query Language) is a relational database management system, meaning it uses tables (rows and columns) to store data.
- NoSQL databases, on the other hand, handle unstructured data and don’t rely on a schema, making them more flexible in terms of data storage and retrieval.
- Interview Tip: Don't just memorize definitions. Be prepared to explain scenarios where you’d use SQL over NoSQL, and vice versa.
2. What is the difference between INNER JOIN and OUTER JOIN?
- An INNER JOIN returns records that have matching values in both tables.
- An OUTER JOIN returns all records from one table and the matched records from the second table. If there's no match, NULL values are returned.
3. How do you optimize a SQL query for better performance?
- Indexing: Create indexes on columns used frequently in WHERE, JOIN, or GROUP BY clauses.
- Query optimization: Use appropriate WHERE clauses to reduce the data set and avoid unnecessary calculations.
- Avoid SELECT *: Always specify the columns you need to reduce the amount of data retrieved.
- Limit results: If you only need a subset of the data, use the LIMIT clause.
4. What are the different types of SQL constraints?
Constraints are used to enforce rules on data in a table. They ensure the accuracy and reliability of the data. The most common types are:
- PRIMARY KEY: Ensures each record is unique and not null.
- FOREIGN KEY: Enforces a relationship between two tables.
- UNIQUE: Ensures all values in a column are unique.
- NOT NULL: Prevents NULL values from being entered into a column.
- CHECK: Ensures a column's values meet a specific condition.
5. What is normalization? What are the different normal forms?
Normalization is the process of organizing data to reduce redundancy and improve data integrity. Here’s a quick overview of normal forms:
- 1NF (First Normal Form): Ensures that all values in a table are atomic (indivisible).
- 2NF (Second Normal Form): Ensures that the table is in 1NF and that all non-key columns are fully dependent on the primary key.
- 3NF (Third Normal Form): Ensures that the table is in 2NF and all columns are independent of each other except for the primary key.
6. What is a subquery?
A subquery is a query within another query. It's used to perform operations that need intermediate results before generating the final query.
Example:
In this case, the subquery calculates the average salary, and the outer query selects employees whose salary is greater than the average.
7. What is the difference between a UNION and a UNION ALL?
- UNION combines the result sets of two SELECT statements and removes duplicates.
- UNION ALL combines the result sets and includes duplicates.
8. What is the difference between WHERE and HAVING clause?
- WHERE filters rows before any groupings are made. It’s used with SELECT, INSERT, UPDATE, or DELETE statements.
- HAVING filters groups after the GROUP BY clause.
9. How would you handle NULL values in SQL?
NULL values can represent missing or unknown data. Here’s how to manage them:
- Use IS NULL or IS NOT NULL in WHERE clauses to filter null values.
- Use COALESCE() or IFNULL() to replace NULL values with default ones.
Example:
10. What is the purpose of the GROUP BY clause?
The GROUP BY clause groups rows with the same values into summary rows. It’s often used with aggregate functions like COUNT, SUM, AVG, etc.
Example:
Here you can find SQL Interview Resources👇
https://news.1rj.ru/str/DataSimplifier
Share with credits: https://news.1rj.ru/str/sqlspecialist
Hope it helps :)
Today, let’s talk about SQL conceptual questions that are often asked in data analyst interviews. These questions test not only your technical skills but also your conceptual understanding of SQL and its real-world applications.
1. What is the difference between SQL and NoSQL?
- SQL (Structured Query Language) is a relational database management system, meaning it uses tables (rows and columns) to store data.
- NoSQL databases, on the other hand, handle unstructured data and don’t rely on a schema, making them more flexible in terms of data storage and retrieval.
- Interview Tip: Don't just memorize definitions. Be prepared to explain scenarios where you’d use SQL over NoSQL, and vice versa.
2. What is the difference between INNER JOIN and OUTER JOIN?
- An INNER JOIN returns records that have matching values in both tables.
- An OUTER JOIN returns all records from one table and the matched records from the second table. If there's no match, NULL values are returned.
3. How do you optimize a SQL query for better performance?
- Indexing: Create indexes on columns used frequently in WHERE, JOIN, or GROUP BY clauses.
- Query optimization: Use appropriate WHERE clauses to reduce the data set and avoid unnecessary calculations.
- Avoid SELECT *: Always specify the columns you need to reduce the amount of data retrieved.
- Limit results: If you only need a subset of the data, use the LIMIT clause.
4. What are the different types of SQL constraints?
Constraints are used to enforce rules on data in a table. They ensure the accuracy and reliability of the data. The most common types are:
- PRIMARY KEY: Ensures each record is unique and not null.
- FOREIGN KEY: Enforces a relationship between two tables.
- UNIQUE: Ensures all values in a column are unique.
- NOT NULL: Prevents NULL values from being entered into a column.
- CHECK: Ensures a column's values meet a specific condition.
5. What is normalization? What are the different normal forms?
Normalization is the process of organizing data to reduce redundancy and improve data integrity. Here’s a quick overview of normal forms:
- 1NF (First Normal Form): Ensures that all values in a table are atomic (indivisible).
- 2NF (Second Normal Form): Ensures that the table is in 1NF and that all non-key columns are fully dependent on the primary key.
- 3NF (Third Normal Form): Ensures that the table is in 2NF and all columns are independent of each other except for the primary key.
6. What is a subquery?
A subquery is a query within another query. It's used to perform operations that need intermediate results before generating the final query.
Example:
SELECT employee_id, name
FROM employees
WHERE salary > (SELECT AVG(salary) FROM employees);
In this case, the subquery calculates the average salary, and the outer query selects employees whose salary is greater than the average.
7. What is the difference between a UNION and a UNION ALL?
- UNION combines the result sets of two SELECT statements and removes duplicates.
- UNION ALL combines the result sets and includes duplicates.
8. What is the difference between WHERE and HAVING clause?
- WHERE filters rows before any groupings are made. It’s used with SELECT, INSERT, UPDATE, or DELETE statements.
- HAVING filters groups after the GROUP BY clause.
9. How would you handle NULL values in SQL?
NULL values can represent missing or unknown data. Here’s how to manage them:
- Use IS NULL or IS NOT NULL in WHERE clauses to filter null values.
- Use COALESCE() or IFNULL() to replace NULL values with default ones.
Example:
SELECT name, COALESCE(age, 0) AS age
FROM employees;
10. What is the purpose of the GROUP BY clause?
The GROUP BY clause groups rows with the same values into summary rows. It’s often used with aggregate functions like COUNT, SUM, AVG, etc.
Example:
SELECT department, COUNT(*)
FROM employees
GROUP BY department;
Here you can find SQL Interview Resources👇
https://news.1rj.ru/str/DataSimplifier
Share with credits: https://news.1rj.ru/str/sqlspecialist
Hope it helps :)
❤5
30 days roadmap to learn Python for Data Analysis👇
Days 1-5: Introduction to Python
1. Day 1: Install Python and a code editor (e.g., Anaconda, Jupyter Notebook).
2. Day 2-5: Learn Python basics (variables, data types, and basic operations).
Days 6-10: Control Flow and Functions
6. Day 6-8: Study control flow (if statements, loops).
9. Day 9-10: Learn about functions and modules in Python.
Days 11-15: Data Structures
11. Day 11-12: Explore lists, tuples, and dictionaries.
13. Day 13-15: Study sets and string manipulation.
Days 16-20: Libraries for Data Analysis
16. Day 16-17: Get familiar with NumPy for numerical operations.
18. Day 18-19: Dive into Pandas for data manipulation.
20. Day 20: Basic data visualization with Matplotlib.
Days 21-25: Data Cleaning and Analysis
21. Day 21-22: Data cleaning and preprocessing using Pandas.
23. Day 23-25: Exploratory data analysis (EDA) techniques.
Days 26-30: Advanced Topics
26. Day 26-27: Introduction to data visualization with Seaborn.
27. Day 28-29: Introduction to machine learning with Scikit-Learn.
30. Day 30: Create a small data analysis project.
Use platforms like Kaggle to find datasets for projects & GeekforGeeks to practice coding problems.
Share with credits: https://news.1rj.ru/str/sqlspecialist
Hope it helps :)
Days 1-5: Introduction to Python
1. Day 1: Install Python and a code editor (e.g., Anaconda, Jupyter Notebook).
2. Day 2-5: Learn Python basics (variables, data types, and basic operations).
Days 6-10: Control Flow and Functions
6. Day 6-8: Study control flow (if statements, loops).
9. Day 9-10: Learn about functions and modules in Python.
Days 11-15: Data Structures
11. Day 11-12: Explore lists, tuples, and dictionaries.
13. Day 13-15: Study sets and string manipulation.
Days 16-20: Libraries for Data Analysis
16. Day 16-17: Get familiar with NumPy for numerical operations.
18. Day 18-19: Dive into Pandas for data manipulation.
20. Day 20: Basic data visualization with Matplotlib.
Days 21-25: Data Cleaning and Analysis
21. Day 21-22: Data cleaning and preprocessing using Pandas.
23. Day 23-25: Exploratory data analysis (EDA) techniques.
Days 26-30: Advanced Topics
26. Day 26-27: Introduction to data visualization with Seaborn.
27. Day 28-29: Introduction to machine learning with Scikit-Learn.
30. Day 30: Create a small data analysis project.
Use platforms like Kaggle to find datasets for projects & GeekforGeeks to practice coding problems.
Share with credits: https://news.1rj.ru/str/sqlspecialist
Hope it helps :)
❤5🔥4👍1
Preparing for a SQL interview?
Focus on mastering these essential topics:
1. Joins: Get comfortable with inner, left, right, and outer joins.
Knowing when to use what kind of join is important!
2. Window Functions: Understand when to use
ROW_NUMBER, RANK(), DENSE_RANK(), LAG, and LEAD for complex analytical queries.
3. Query Execution Order: Know the sequence from FROM to
ORDER BY. This is crucial for writing efficient, error-free queries.
4. Common Table Expressions (CTEs): Use CTEs to simplify and structure complex queries for better readability.
5. Aggregations & Window Functions: Combine aggregate functions with window functions for in-depth data analysis.
6. Subqueries: Learn how to use subqueries effectively within main SQL statements for complex data manipulations.
7. Handling NULLs: Be adept at managing NULL values to ensure accurate data processing and avoid potential pitfalls.
8. Indexing: Understand how proper indexing can significantly boost query performance.
9. GROUP BY & HAVING: Master grouping data and filtering groups with HAVING to refine your query results.
10. String Manipulation Functions: Get familiar with string functions like CONCAT, SUBSTRING, and REPLACE to handle text data efficiently.
11. Set Operations: Know how to use UNION, INTERSECT, and EXCEPT to combine or compare result sets.
12. Optimizing Queries: Learn techniques to optimize your queries for performance, especially with large datasets.
If we master/ Practice in these topics we can track any SQL interviews..
Like this post if you need more 👍❤️
Hope it helps :)
Focus on mastering these essential topics:
1. Joins: Get comfortable with inner, left, right, and outer joins.
Knowing when to use what kind of join is important!
2. Window Functions: Understand when to use
ROW_NUMBER, RANK(), DENSE_RANK(), LAG, and LEAD for complex analytical queries.
3. Query Execution Order: Know the sequence from FROM to
ORDER BY. This is crucial for writing efficient, error-free queries.
4. Common Table Expressions (CTEs): Use CTEs to simplify and structure complex queries for better readability.
5. Aggregations & Window Functions: Combine aggregate functions with window functions for in-depth data analysis.
6. Subqueries: Learn how to use subqueries effectively within main SQL statements for complex data manipulations.
7. Handling NULLs: Be adept at managing NULL values to ensure accurate data processing and avoid potential pitfalls.
8. Indexing: Understand how proper indexing can significantly boost query performance.
9. GROUP BY & HAVING: Master grouping data and filtering groups with HAVING to refine your query results.
10. String Manipulation Functions: Get familiar with string functions like CONCAT, SUBSTRING, and REPLACE to handle text data efficiently.
11. Set Operations: Know how to use UNION, INTERSECT, and EXCEPT to combine or compare result sets.
12. Optimizing Queries: Learn techniques to optimize your queries for performance, especially with large datasets.
If we master/ Practice in these topics we can track any SQL interviews..
Like this post if you need more 👍❤️
Hope it helps :)
❤11👍2🔥1
Essential Skills Excel for Data Analysts 🚀
1️⃣ Data Cleaning & Transformation
Remove Duplicates – Ensure unique records.
Find & Replace – Quick data modifications.
Text Functions – TRIM, LEN, LEFT, RIGHT, MID, PROPER.
Data Validation – Restrict input values.
2️⃣ Data Analysis & Manipulation
Sorting & Filtering – Organize and extract key insights.
Conditional Formatting – Highlight trends, outliers.
Pivot Tables – Summarize large datasets efficiently.
Power Query – Automate data transformation.
3️⃣ Essential Formulas & Functions
Lookup Functions – VLOOKUP, HLOOKUP, XLOOKUP, INDEX-MATCH.
Logical Functions – IF, AND, OR, IFERROR, IFS.
Aggregation Functions – SUM, AVERAGE, MIN, MAX, COUNT, COUNTA.
Text Functions – CONCATENATE, TEXTJOIN, SUBSTITUTE.
4️⃣ Data Visualization
Charts & Graphs – Bar, Line, Pie, Scatter, Histogram.
Sparklines – Miniature charts inside cells.
Conditional Formatting – Color scales, data bars.
Dashboard Creation – Interactive and dynamic reports.
5️⃣ Advanced Excel Techniques
Array Formulas – Dynamic calculations with multiple values.
Power Pivot & DAX – Advanced data modeling.
What-If Analysis – Goal Seek, Scenario Manager.
Macros & VBA – Automate repetitive tasks.
6️⃣ Data Import & Export
CSV & TXT Files – Import and clean raw data.
Power Query – Connect to databases, web sources.
Exporting Reports – PDF, CSV, Excel formats.
Here you can find some free Excel books & useful resources: https://news.1rj.ru/str/excel_data
Hope it helps :)
#dataanalyst
1️⃣ Data Cleaning & Transformation
Remove Duplicates – Ensure unique records.
Find & Replace – Quick data modifications.
Text Functions – TRIM, LEN, LEFT, RIGHT, MID, PROPER.
Data Validation – Restrict input values.
2️⃣ Data Analysis & Manipulation
Sorting & Filtering – Organize and extract key insights.
Conditional Formatting – Highlight trends, outliers.
Pivot Tables – Summarize large datasets efficiently.
Power Query – Automate data transformation.
3️⃣ Essential Formulas & Functions
Lookup Functions – VLOOKUP, HLOOKUP, XLOOKUP, INDEX-MATCH.
Logical Functions – IF, AND, OR, IFERROR, IFS.
Aggregation Functions – SUM, AVERAGE, MIN, MAX, COUNT, COUNTA.
Text Functions – CONCATENATE, TEXTJOIN, SUBSTITUTE.
4️⃣ Data Visualization
Charts & Graphs – Bar, Line, Pie, Scatter, Histogram.
Sparklines – Miniature charts inside cells.
Conditional Formatting – Color scales, data bars.
Dashboard Creation – Interactive and dynamic reports.
5️⃣ Advanced Excel Techniques
Array Formulas – Dynamic calculations with multiple values.
Power Pivot & DAX – Advanced data modeling.
What-If Analysis – Goal Seek, Scenario Manager.
Macros & VBA – Automate repetitive tasks.
6️⃣ Data Import & Export
CSV & TXT Files – Import and clean raw data.
Power Query – Connect to databases, web sources.
Exporting Reports – PDF, CSV, Excel formats.
Here you can find some free Excel books & useful resources: https://news.1rj.ru/str/excel_data
Hope it helps :)
#dataanalyst
❤8
SQL Cheat Sheet For Data Analysts 📚 ✅
1️⃣ Basic Aggregates
⦁ SUM() – Adds up values:
SELECT SUM(sales) FROM orders;
⦁ AVG() – Calculates average:
SELECT AVG(score) FROM tests;
⦁ MIN() / MAX() – Smallest/largest value:
SELECT MIN(age), MAX(age) FROM users;
⦁ COUNT() – Counts rows:
SELECT COUNT(*) FROM customers;
2️⃣ Conditional Logic
⦁ CASE WHEN – If/else logic:
⦁ COALESCE() – Returns first non-null:
SELECT COALESCE(phone, 'N/A') FROM contacts;
3️⃣ String Functions
⦁ LEFT(), RIGHT(), SUBSTRING() – Extract text:
SELECT LEFT(name, 3) FROM employees;
⦁ LENGTH() – Counts characters:
SELECT LENGTH(address) FROM users;
⦁ TRIM(), UPPER(), LOWER() – Clean/change case:
SELECT TRIM(email), UPPER(city) FROM users;
⦁ CONCAT() – Combine text:
SELECT CONCAT(first_name, ' ', last_name) FROM users;
4️⃣ Lookup/Join
⦁ JOIN – Combine tables:
⦁ IN / EXISTS – Check for values:
SELECT * FROM products WHERE category_id IN (1,2,3);
5️⃣ Date & Time
⦁ CURRENT_DATE, CURRENT_TIMESTAMP – Today/now:
SELECT CURRENT_DATE;
⦁ EXTRACT() – Get year/month/day:
SELECT EXTRACT(YEAR FROM order_date) FROM orders;
⦁ DATEDIFF() – Days between dates:
SELECT DATEDIFF('2025-07-08', '2025-01-01');
6️⃣ Data Cleaning
⦁ DISTINCT – Unique values:
SELECT DISTINCT city FROM customers;
⦁ REPLACE() – Replace text:
SELECT REPLACE(email, '.com', '.org') FROM users;
⦁ NULLIF() – Set value to NULL if condition met:
SELECT NULLIF(status, 'unknown') FROM orders;
7️⃣ Advanced Functions
⦁ GROUP BY – Aggregate by group:
SELECT department, COUNT(*) FROM employees GROUP BY department;
⦁ HAVING – Filter after aggregation:
SELECT department, COUNT(*) FROM employees GROUP BY department HAVING COUNT(*) > 5;
⦁ WINDOW FUNCTIONS – Running totals, ranks:
SELECT name, salary, RANK() OVER (ORDER BY salary DESC) FROM staff;
8️⃣ Views & CTEs
⦁ VIEW – Save a query:
CREATE VIEW top_customers AS SELECT * FROM customers WHERE spend > 1000;
⦁ CTE – Temporary result set:
Free Resources to learn SQL: https://whatsapp.com/channel/0029VanC5rODzgT6TiTGoa1v
ENJOY LEARNING👍 👍
1️⃣ Basic Aggregates
⦁ SUM() – Adds up values:
SELECT SUM(sales) FROM orders;
⦁ AVG() – Calculates average:
SELECT AVG(score) FROM tests;
⦁ MIN() / MAX() – Smallest/largest value:
SELECT MIN(age), MAX(age) FROM users;
⦁ COUNT() – Counts rows:
SELECT COUNT(*) FROM customers;
2️⃣ Conditional Logic
⦁ CASE WHEN – If/else logic:
SELECT name,
CASE WHEN score > 50 THEN 'Pass' ELSE 'Fail' END AS result
FROM students;
⦁ COALESCE() – Returns first non-null:
SELECT COALESCE(phone, 'N/A') FROM contacts;
3️⃣ String Functions
⦁ LEFT(), RIGHT(), SUBSTRING() – Extract text:
SELECT LEFT(name, 3) FROM employees;
⦁ LENGTH() – Counts characters:
SELECT LENGTH(address) FROM users;
⦁ TRIM(), UPPER(), LOWER() – Clean/change case:
SELECT TRIM(email), UPPER(city) FROM users;
⦁ CONCAT() – Combine text:
SELECT CONCAT(first_name, ' ', last_name) FROM users;
4️⃣ Lookup/Join
⦁ JOIN – Combine tables:
SELECT o.order_id, c.name
FROM orders o
JOIN customers c ON o.customer_id = c.id;
⦁ IN / EXISTS – Check for values:
SELECT * FROM products WHERE category_id IN (1,2,3);
5️⃣ Date & Time
⦁ CURRENT_DATE, CURRENT_TIMESTAMP – Today/now:
SELECT CURRENT_DATE;
⦁ EXTRACT() – Get year/month/day:
SELECT EXTRACT(YEAR FROM order_date) FROM orders;
⦁ DATEDIFF() – Days between dates:
SELECT DATEDIFF('2025-07-08', '2025-01-01');
6️⃣ Data Cleaning
⦁ DISTINCT – Unique values:
SELECT DISTINCT city FROM customers;
⦁ REPLACE() – Replace text:
SELECT REPLACE(email, '.com', '.org') FROM users;
⦁ NULLIF() – Set value to NULL if condition met:
SELECT NULLIF(status, 'unknown') FROM orders;
7️⃣ Advanced Functions
⦁ GROUP BY – Aggregate by group:
SELECT department, COUNT(*) FROM employees GROUP BY department;
⦁ HAVING – Filter after aggregation:
SELECT department, COUNT(*) FROM employees GROUP BY department HAVING COUNT(*) > 5;
⦁ WINDOW FUNCTIONS – Running totals, ranks:
SELECT name, salary, RANK() OVER (ORDER BY salary DESC) FROM staff;
8️⃣ Views & CTEs
⦁ VIEW – Save a query:
CREATE VIEW top_customers AS SELECT * FROM customers WHERE spend > 1000;
⦁ CTE – Temporary result set:
WITH high_sales AS (
SELECT * FROM sales WHERE amount > 1000
)
SELECT * FROM high_sales;
Free Resources to learn SQL: https://whatsapp.com/channel/0029VanC5rODzgT6TiTGoa1v
ENJOY LEARNING
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❤11👏1
𝗗𝗮𝘁𝗮 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀 𝗥𝗼𝗮𝗱𝗺𝗮𝗽
𝟭. 𝗣𝗿𝗼𝗴𝗿𝗮𝗺𝗺𝗶𝗻𝗴 𝗟𝗮𝗻𝗴𝘂𝗮𝗴𝗲𝘀: Master Python, SQL, and R for data manipulation and analysis.
𝟮. 𝗗𝗮𝘁𝗮 𝗠𝗮𝗻𝗶𝗽𝘂𝗹𝗮𝘁𝗶𝗼𝗻 𝗮𝗻𝗱 𝗣𝗿𝗼𝗰𝗲𝘀𝘀𝗶𝗻𝗴: Use Excel, Pandas, and ETL tools like Alteryx and Talend for data processing.
𝟯. 𝗗𝗮𝘁𝗮 𝗩𝗶𝘀𝘂𝗮𝗹𝗶𝘇𝗮𝘁𝗶𝗼𝗻: Learn Tableau, Power BI, and Matplotlib/Seaborn for creating insightful visualizations.
𝟰. 𝗦𝘁𝗮𝘁𝗶𝘀𝘁𝗶𝗰𝘀 𝗮𝗻𝗱 𝗠𝗮𝘁𝗵𝗲𝗺𝗮𝘁𝗶𝗰𝘀: Understand Denoscriptive and Inferential Statistics, Probability, Regression, and Time Series Analysis.
𝟱. 𝗠𝗮𝗰𝗵𝗶𝗻𝗲 𝗟𝗲𝗮𝗿𝗻𝗶𝗻𝗴: Get proficient in Supervised and Unsupervised Learning, along with Time Series Forecasting.
𝟲. 𝗕𝗶𝗴 𝗗𝗮𝘁𝗮 𝗧𝗼𝗼𝗹𝘀: Utilize Google BigQuery, AWS Redshift, and NoSQL databases like MongoDB for large-scale data management.
𝟳. 𝗠𝗼𝗻𝗶𝘁𝗼𝗿𝗶𝗻𝗴 𝗮𝗻𝗱 𝗥𝗲𝗽𝗼𝗿𝘁𝗶𝗻𝗴: Implement Data Quality Monitoring (Great Expectations) and Performance Tracking (Prometheus, Grafana).
𝟴. 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀 𝗧𝗼𝗼𝗹𝘀: Work with Data Orchestration tools (Airflow, Prefect) and visualization tools like D3.js and Plotly.
𝟵. 𝗥𝗲𝘀𝗼𝘂𝗿𝗰𝗲 𝗠𝗮𝗻𝗮𝗴𝗲𝗿: Manage resources using Jupyter Notebooks and Power BI.
𝟭𝟬. 𝗗𝗮𝘁𝗮 𝗚𝗼𝘃𝗲𝗿𝗻𝗮𝗻𝗰𝗲 𝗮𝗻𝗱 𝗘𝘁𝗵𝗶𝗰𝘀: Ensure compliance with GDPR, Data Privacy, and Data Quality standards.
𝟭𝟭. 𝗖𝗹𝗼𝘂𝗱 𝗖𝗼𝗺𝗽𝘂𝘁𝗶𝗻𝗴: Leverage AWS, Google Cloud, and Azure for scalable data solutions.
𝟭𝟮. 𝗗𝗮𝘁𝗮 𝗪𝗿𝗮𝗻𝗴𝗹𝗶𝗻𝗴 𝗮𝗻𝗱 𝗖𝗹𝗲𝗮𝗻𝗶𝗻𝗴: Master data cleaning (OpenRefine, Trifacta) and transformation techniques.
Data Analytics Resources
👇👇
https://news.1rj.ru/str/sqlspecialist
Hope this helps you 😊
𝟭. 𝗣𝗿𝗼𝗴𝗿𝗮𝗺𝗺𝗶𝗻𝗴 𝗟𝗮𝗻𝗴𝘂𝗮𝗴𝗲𝘀: Master Python, SQL, and R for data manipulation and analysis.
𝟮. 𝗗𝗮𝘁𝗮 𝗠𝗮𝗻𝗶𝗽𝘂𝗹𝗮𝘁𝗶𝗼𝗻 𝗮𝗻𝗱 𝗣𝗿𝗼𝗰𝗲𝘀𝘀𝗶𝗻𝗴: Use Excel, Pandas, and ETL tools like Alteryx and Talend for data processing.
𝟯. 𝗗𝗮𝘁𝗮 𝗩𝗶𝘀𝘂𝗮𝗹𝗶𝘇𝗮𝘁𝗶𝗼𝗻: Learn Tableau, Power BI, and Matplotlib/Seaborn for creating insightful visualizations.
𝟰. 𝗦𝘁𝗮𝘁𝗶𝘀𝘁𝗶𝗰𝘀 𝗮𝗻𝗱 𝗠𝗮𝘁𝗵𝗲𝗺𝗮𝘁𝗶𝗰𝘀: Understand Denoscriptive and Inferential Statistics, Probability, Regression, and Time Series Analysis.
𝟱. 𝗠𝗮𝗰𝗵𝗶𝗻𝗲 𝗟𝗲𝗮𝗿𝗻𝗶𝗻𝗴: Get proficient in Supervised and Unsupervised Learning, along with Time Series Forecasting.
𝟲. 𝗕𝗶𝗴 𝗗𝗮𝘁𝗮 𝗧𝗼𝗼𝗹𝘀: Utilize Google BigQuery, AWS Redshift, and NoSQL databases like MongoDB for large-scale data management.
𝟳. 𝗠𝗼𝗻𝗶𝘁𝗼𝗿𝗶𝗻𝗴 𝗮𝗻𝗱 𝗥𝗲𝗽𝗼𝗿𝘁𝗶𝗻𝗴: Implement Data Quality Monitoring (Great Expectations) and Performance Tracking (Prometheus, Grafana).
𝟴. 𝗔𝗻𝗮𝗹𝘆𝘁𝗶𝗰𝘀 𝗧𝗼𝗼𝗹𝘀: Work with Data Orchestration tools (Airflow, Prefect) and visualization tools like D3.js and Plotly.
𝟵. 𝗥𝗲𝘀𝗼𝘂𝗿𝗰𝗲 𝗠𝗮𝗻𝗮𝗴𝗲𝗿: Manage resources using Jupyter Notebooks and Power BI.
𝟭𝟬. 𝗗𝗮𝘁𝗮 𝗚𝗼𝘃𝗲𝗿𝗻𝗮𝗻𝗰𝗲 𝗮𝗻𝗱 𝗘𝘁𝗵𝗶𝗰𝘀: Ensure compliance with GDPR, Data Privacy, and Data Quality standards.
𝟭𝟭. 𝗖𝗹𝗼𝘂𝗱 𝗖𝗼𝗺𝗽𝘂𝘁𝗶𝗻𝗴: Leverage AWS, Google Cloud, and Azure for scalable data solutions.
𝟭𝟮. 𝗗𝗮𝘁𝗮 𝗪𝗿𝗮𝗻𝗴𝗹𝗶𝗻𝗴 𝗮𝗻𝗱 𝗖𝗹𝗲𝗮𝗻𝗶𝗻𝗴: Master data cleaning (OpenRefine, Trifacta) and transformation techniques.
Data Analytics Resources
👇👇
https://news.1rj.ru/str/sqlspecialist
Hope this helps you 😊
❤4
Junior-level Data Analyst interview questions:
Introduction and Background
1. Can you tell me about your background and how you became interested in data analysis?
2. What do you know about our company/organization?
3. Why do you want to work as a data analyst?
Data Analysis and Interpretation
1. What is your experience with data analysis tools like Excel, SQL, or Tableau?
2. How would you approach analyzing a large dataset to identify trends and patterns?
3. Can you explain the concept of correlation versus causation?
4. How do you handle missing or incomplete data?
5. Can you walk me through a time when you had to interpret complex data results?
Technical Skills
1. Write a SQL query to extract data from a database.
2. How do you create a pivot table in Excel?
3. Can you explain the difference between a histogram and a box plot?
4. How do you perform data visualization using Tableau or Power BI?
5. Can you write a simple Python or R noscript to manipulate data?
Statistics and Math
1. What is the difference between mean, median, and mode?
2. Can you explain the concept of standard deviation and variance?
3. How do you calculate probability and confidence intervals?
4. Can you describe a time when you applied statistical concepts to a real-world problem?
5. How do you approach hypothesis testing?
Communication and Storytelling
1. Can you explain a complex data concept to a non-technical person?
2. How do you present data insights to stakeholders?
3. Can you walk me through a time when you had to communicate data results to a team?
4. How do you create effective data visualizations?
5. Can you tell a story using data?
Case Studies and Scenarios
1. You are given a dataset with customer purchase history. How would you analyze it to identify trends?
2. A company wants to increase sales. How would you use data to inform marketing strategies?
3. You notice a discrepancy in sales data. How would you investigate and resolve the issue?
4. Can you describe a time when you had to work with a stakeholder to understand their data needs?
5. How would you prioritize data projects with limited resources?
Behavioral Questions
1. Can you describe a time when you overcame a difficult data analysis challenge?
2. How do you handle tight deadlines and multiple projects?
3. Can you tell me about a project you worked on and your role in it?
4. How do you stay up-to-date with new data tools and technologies?
5. Can you describe a time when you received feedback on your data analysis work?
Final Questions
1. Do you have any questions about the company or role?
2. What do you think sets you apart from other candidates?
3. Can you summarize your experience and qualifications?
4. What are your long-term career goals?
Hope this helps you 😊
Introduction and Background
1. Can you tell me about your background and how you became interested in data analysis?
2. What do you know about our company/organization?
3. Why do you want to work as a data analyst?
Data Analysis and Interpretation
1. What is your experience with data analysis tools like Excel, SQL, or Tableau?
2. How would you approach analyzing a large dataset to identify trends and patterns?
3. Can you explain the concept of correlation versus causation?
4. How do you handle missing or incomplete data?
5. Can you walk me through a time when you had to interpret complex data results?
Technical Skills
1. Write a SQL query to extract data from a database.
2. How do you create a pivot table in Excel?
3. Can you explain the difference between a histogram and a box plot?
4. How do you perform data visualization using Tableau or Power BI?
5. Can you write a simple Python or R noscript to manipulate data?
Statistics and Math
1. What is the difference between mean, median, and mode?
2. Can you explain the concept of standard deviation and variance?
3. How do you calculate probability and confidence intervals?
4. Can you describe a time when you applied statistical concepts to a real-world problem?
5. How do you approach hypothesis testing?
Communication and Storytelling
1. Can you explain a complex data concept to a non-technical person?
2. How do you present data insights to stakeholders?
3. Can you walk me through a time when you had to communicate data results to a team?
4. How do you create effective data visualizations?
5. Can you tell a story using data?
Case Studies and Scenarios
1. You are given a dataset with customer purchase history. How would you analyze it to identify trends?
2. A company wants to increase sales. How would you use data to inform marketing strategies?
3. You notice a discrepancy in sales data. How would you investigate and resolve the issue?
4. Can you describe a time when you had to work with a stakeholder to understand their data needs?
5. How would you prioritize data projects with limited resources?
Behavioral Questions
1. Can you describe a time when you overcame a difficult data analysis challenge?
2. How do you handle tight deadlines and multiple projects?
3. Can you tell me about a project you worked on and your role in it?
4. How do you stay up-to-date with new data tools and technologies?
5. Can you describe a time when you received feedback on your data analysis work?
Final Questions
1. Do you have any questions about the company or role?
2. What do you think sets you apart from other candidates?
3. Can you summarize your experience and qualifications?
4. What are your long-term career goals?
Hope this helps you 😊
❤21👍1
SQL 𝗢𝗿𝗱𝗲𝗿 𝗢𝗳 𝗘𝘅𝗲𝗰𝘂𝘁𝗶𝗼𝗻 ↓
1 → FROM (Tables selected).
2 → WHERE (Filters applied).
3 → GROUP BY (Rows grouped).
4 → HAVING (Filter on grouped data).
5 → SELECT (Columns selected).
6 → ORDER BY (Sort the data).
7 → LIMIT (Restrict number of rows).
𝗖𝗼𝗺𝗺𝗼𝗻 𝗤𝘂𝗲𝗿𝗶𝗲𝘀 𝗧𝗼 𝗣𝗿𝗮𝗰𝘁𝗶𝗰𝗲 ↓
↬ Find the second-highest salary:
SELECT MAX(Salary) FROM Employees WHERE Salary < (SELECT MAX(Salary) FROM Employees);
↬ Find duplicate records:
SELECT Name, COUNT(*)
FROM Emp
GROUP BY Name
HAVING COUNT(*) > 1;
1 → FROM (Tables selected).
2 → WHERE (Filters applied).
3 → GROUP BY (Rows grouped).
4 → HAVING (Filter on grouped data).
5 → SELECT (Columns selected).
6 → ORDER BY (Sort the data).
7 → LIMIT (Restrict number of rows).
𝗖𝗼𝗺𝗺𝗼𝗻 𝗤𝘂𝗲𝗿𝗶𝗲𝘀 𝗧𝗼 𝗣𝗿𝗮𝗰𝘁𝗶𝗰𝗲 ↓
↬ Find the second-highest salary:
SELECT MAX(Salary) FROM Employees WHERE Salary < (SELECT MAX(Salary) FROM Employees);
↬ Find duplicate records:
SELECT Name, COUNT(*)
FROM Emp
GROUP BY Name
HAVING COUNT(*) > 1;
❤9
🚀 Complete Roadmap to Become a Data Scientist in 5 Months
📅 Week 1-2: Fundamentals
✅ Day 1-3: Introduction to Data Science, its applications, and roles.
✅ Day 4-7: Brush up on Python programming 🐍.
✅ Day 8-10: Learn basic statistics 📊 and probability 🎲.
🔍 Week 3-4: Data Manipulation & Visualization
📝 Day 11-15: Master Pandas for data manipulation.
📈 Day 16-20: Learn Matplotlib & Seaborn for data visualization.
🤖 Week 5-6: Machine Learning Foundations
🔬 Day 21-25: Introduction to scikit-learn.
📊 Day 26-30: Learn Linear & Logistic Regression.
🏗 Week 7-8: Advanced Machine Learning
🌳 Day 31-35: Explore Decision Trees & Random Forests.
📌 Day 36-40: Learn Clustering (K-Means, DBSCAN) & Dimensionality Reduction.
🧠 Week 9-10: Deep Learning
🤖 Day 41-45: Basics of Neural Networks with TensorFlow/Keras.
📸 Day 46-50: Learn CNNs & RNNs for image & text data.
🏛 Week 11-12: Data Engineering
🗄 Day 51-55: Learn SQL & Databases.
🧹 Day 56-60: Data Preprocessing & Cleaning.
📊 Week 13-14: Model Evaluation & Optimization
📏 Day 61-65: Learn Cross-validation & Hyperparameter Tuning.
📉 Day 66-70: Understand Evaluation Metrics (Accuracy, Precision, Recall, F1-score).
🏗 Week 15-16: Big Data & Tools
🐘 Day 71-75: Introduction to Big Data Technologies (Hadoop, Spark).
☁️ Day 76-80: Learn Cloud Computing (AWS, GCP, Azure).
🚀 Week 17-18: Deployment & Production
🛠 Day 81-85: Deploy models using Flask or FastAPI.
📦 Day 86-90: Learn Docker & Cloud Deployment (AWS, Heroku).
🎯 Week 19-20: Specialization
📝 Day 91-95: Choose NLP or Computer Vision, based on your interest.
🏆 Week 21-22: Projects & Portfolio
📂 Day 96-100: Work on Personal Data Science Projects.
💬 Week 23-24: Soft Skills & Networking
🎤 Day 101-105: Improve Communication & Presentation Skills.
🌐 Day 106-110: Attend Online Meetups & Forums.
🎯 Week 25-26: Interview Preparation
💻 Day 111-115: Practice Coding Interviews (LeetCode, HackerRank).
📂 Day 116-120: Review your projects & prepare for discussions.
👨💻 Week 27-28: Apply for Jobs
📩 Day 121-125: Start applying for Entry-Level Data Scientist positions.
🎤 Week 29-30: Interviews
📝 Day 126-130: Attend Interviews & Practice Whiteboard Problems.
🔄 Week 31-32: Continuous Learning
📰 Day 131-135: Stay updated with the Latest Data Science Trends.
🏆 Week 33-34: Accepting Offers
📝 Day 136-140: Evaluate job offers & Negotiate Your Salary.
🏢 Week 35-36: Settling In
🎯 Day 141-150: Start your New Data Science Job, adapt & keep learning!
🎉 Enjoy Learning & Build Your Dream Career in Data Science! 🚀🔥
📅 Week 1-2: Fundamentals
✅ Day 1-3: Introduction to Data Science, its applications, and roles.
✅ Day 4-7: Brush up on Python programming 🐍.
✅ Day 8-10: Learn basic statistics 📊 and probability 🎲.
🔍 Week 3-4: Data Manipulation & Visualization
📝 Day 11-15: Master Pandas for data manipulation.
📈 Day 16-20: Learn Matplotlib & Seaborn for data visualization.
🤖 Week 5-6: Machine Learning Foundations
🔬 Day 21-25: Introduction to scikit-learn.
📊 Day 26-30: Learn Linear & Logistic Regression.
🏗 Week 7-8: Advanced Machine Learning
🌳 Day 31-35: Explore Decision Trees & Random Forests.
📌 Day 36-40: Learn Clustering (K-Means, DBSCAN) & Dimensionality Reduction.
🧠 Week 9-10: Deep Learning
🤖 Day 41-45: Basics of Neural Networks with TensorFlow/Keras.
📸 Day 46-50: Learn CNNs & RNNs for image & text data.
🏛 Week 11-12: Data Engineering
🗄 Day 51-55: Learn SQL & Databases.
🧹 Day 56-60: Data Preprocessing & Cleaning.
📊 Week 13-14: Model Evaluation & Optimization
📏 Day 61-65: Learn Cross-validation & Hyperparameter Tuning.
📉 Day 66-70: Understand Evaluation Metrics (Accuracy, Precision, Recall, F1-score).
🏗 Week 15-16: Big Data & Tools
🐘 Day 71-75: Introduction to Big Data Technologies (Hadoop, Spark).
☁️ Day 76-80: Learn Cloud Computing (AWS, GCP, Azure).
🚀 Week 17-18: Deployment & Production
🛠 Day 81-85: Deploy models using Flask or FastAPI.
📦 Day 86-90: Learn Docker & Cloud Deployment (AWS, Heroku).
🎯 Week 19-20: Specialization
📝 Day 91-95: Choose NLP or Computer Vision, based on your interest.
🏆 Week 21-22: Projects & Portfolio
📂 Day 96-100: Work on Personal Data Science Projects.
💬 Week 23-24: Soft Skills & Networking
🎤 Day 101-105: Improve Communication & Presentation Skills.
🌐 Day 106-110: Attend Online Meetups & Forums.
🎯 Week 25-26: Interview Preparation
💻 Day 111-115: Practice Coding Interviews (LeetCode, HackerRank).
📂 Day 116-120: Review your projects & prepare for discussions.
👨💻 Week 27-28: Apply for Jobs
📩 Day 121-125: Start applying for Entry-Level Data Scientist positions.
🎤 Week 29-30: Interviews
📝 Day 126-130: Attend Interviews & Practice Whiteboard Problems.
🔄 Week 31-32: Continuous Learning
📰 Day 131-135: Stay updated with the Latest Data Science Trends.
🏆 Week 33-34: Accepting Offers
📝 Day 136-140: Evaluate job offers & Negotiate Your Salary.
🏢 Week 35-36: Settling In
🎯 Day 141-150: Start your New Data Science Job, adapt & keep learning!
🎉 Enjoy Learning & Build Your Dream Career in Data Science! 🚀🔥
❤10👍2
Step-by-step guide to become a Data Analyst in 2025—📊
1. Learn the Fundamentals:
Start with Excel, basic statistics, and data visualization concepts.
2. Pick Up Key Tools & Languages:
Master SQL, Python (or R), and data visualization tools like Tableau or Power BI.
3. Get Formal Education or Certification:
A bachelor’s degree in a relevant field (like Computer Science, Math, or Economics) helps, but you can also do online courses or certifications in data analytics.
4. Build Hands-on Experience:
Work on real-world projects—use Kaggle datasets, internships, or freelance gigs to practice data cleaning, analysis, and visualization.
5. Create a Portfolio:
Showcase your projects on GitHub or a personal website. Include dashboards, reports, and code samples.
6. Develop Soft Skills:
Focus on communication, problem-solving, teamwork, and attention to detail—these are just as important as technical skills.
7. Apply for Entry-Level Jobs:
Look for roles like “Junior Data Analyst” or “Business Analyst.” Tailor your resume to highlight your skills and portfolio.
8. Keep Learning:
Stay updated with new tools (like AI-driven analytics), trends, and advanced topics such as machine learning or domain-specific analytics.
React ❤️ for more
1. Learn the Fundamentals:
Start with Excel, basic statistics, and data visualization concepts.
2. Pick Up Key Tools & Languages:
Master SQL, Python (or R), and data visualization tools like Tableau or Power BI.
3. Get Formal Education or Certification:
A bachelor’s degree in a relevant field (like Computer Science, Math, or Economics) helps, but you can also do online courses or certifications in data analytics.
4. Build Hands-on Experience:
Work on real-world projects—use Kaggle datasets, internships, or freelance gigs to practice data cleaning, analysis, and visualization.
5. Create a Portfolio:
Showcase your projects on GitHub or a personal website. Include dashboards, reports, and code samples.
6. Develop Soft Skills:
Focus on communication, problem-solving, teamwork, and attention to detail—these are just as important as technical skills.
7. Apply for Entry-Level Jobs:
Look for roles like “Junior Data Analyst” or “Business Analyst.” Tailor your resume to highlight your skills and portfolio.
8. Keep Learning:
Stay updated with new tools (like AI-driven analytics), trends, and advanced topics such as machine learning or domain-specific analytics.
React ❤️ for more
❤11🥰1
✅ Data Analytics Roadmap for Freshers in 2025 🚀📊
1️⃣ Understand What a Data Analyst Does
🔍 Analyze data, find insights, create dashboards, support business decisions.
2️⃣ Start with Excel
📈 Learn:
– Basic formulas
– Charts & Pivot Tables
– Data cleaning
💡 Excel is still the #1 tool in many companies.
3️⃣ Learn SQL
🧩 SQL helps you pull and analyze data from databases.
Start with:
– SELECT, WHERE, JOIN, GROUP BY
🛠️ Practice on platforms like W3Schools or Mode Analytics.
4️⃣ Pick a Programming Language
🐍 Start with Python (easier) or R
– Learn pandas, matplotlib, numpy
– Do small projects (e.g. analyze sales data)
5️⃣ Data Visualization Tools
📊 Learn:
– Power BI or Tableau
– Build simple dashboards
💡 Start with free versions or YouTube tutorials.
6️⃣ Practice with Real Data
🔍 Use sites like Kaggle or Data.gov
– Clean, analyze, visualize
– Try small case studies (sales report, customer trends)
7️⃣ Create a Portfolio
💻 Share projects on:
– GitHub
– Notion or a simple website
📌 Add visuals + brief explanations of your insights.
8️⃣ Improve Soft Skills
🗣️ Focus on:
– Presenting data in simple words
– Asking good questions
– Thinking critically about patterns
9️⃣ Certifications to Stand Out
🎓 Try:
– Google Data Analytics (Coursera)
– IBM Data Analyst
– LinkedIn Learning basics
🔟 Apply for Internships & Entry Jobs
🎯 Titles to look for:
– Data Analyst (Intern)
– Junior Analyst
– Business Analyst
💬 React ❤️ for more!
1️⃣ Understand What a Data Analyst Does
🔍 Analyze data, find insights, create dashboards, support business decisions.
2️⃣ Start with Excel
📈 Learn:
– Basic formulas
– Charts & Pivot Tables
– Data cleaning
💡 Excel is still the #1 tool in many companies.
3️⃣ Learn SQL
🧩 SQL helps you pull and analyze data from databases.
Start with:
– SELECT, WHERE, JOIN, GROUP BY
🛠️ Practice on platforms like W3Schools or Mode Analytics.
4️⃣ Pick a Programming Language
🐍 Start with Python (easier) or R
– Learn pandas, matplotlib, numpy
– Do small projects (e.g. analyze sales data)
5️⃣ Data Visualization Tools
📊 Learn:
– Power BI or Tableau
– Build simple dashboards
💡 Start with free versions or YouTube tutorials.
6️⃣ Practice with Real Data
🔍 Use sites like Kaggle or Data.gov
– Clean, analyze, visualize
– Try small case studies (sales report, customer trends)
7️⃣ Create a Portfolio
💻 Share projects on:
– GitHub
– Notion or a simple website
📌 Add visuals + brief explanations of your insights.
8️⃣ Improve Soft Skills
🗣️ Focus on:
– Presenting data in simple words
– Asking good questions
– Thinking critically about patterns
9️⃣ Certifications to Stand Out
🎓 Try:
– Google Data Analytics (Coursera)
– IBM Data Analyst
– LinkedIn Learning basics
🔟 Apply for Internships & Entry Jobs
🎯 Titles to look for:
– Data Analyst (Intern)
– Junior Analyst
– Business Analyst
💬 React ❤️ for more!
❤14👍2
🚀 Excel vs SQL vs Python (Pandas):
1️⃣ Filtering Data
↳ Excel: =FILTER(A2:D100, B2:B100>50) (Excel 365 users)
↳ SQL: SELECT * FROM table WHERE column > 50;
↳ Python: df_filtered = df[df['column'] > 50]
2️⃣ Sorting Data
↳ Excel: Data → Sort (or =SORT(A2:A100, 1, TRUE))
↳ SQL: SELECT * FROM table ORDER BY column ASC;
↳ Python: df_sorted = df.sort_values(by="column")
3️⃣ Counting Rows
↳ Excel: =COUNTA(A:A)
↳ SQL: SELECT COUNT(*) FROM table;
↳ Python: row_count = len(df)
4️⃣ Removing Duplicates
↳ Excel: Data → Remove Duplicates
↳ SQL: SELECT DISTINCT * FROM table;
↳ Python: df_unique = df.drop_duplicates()
5️⃣ Joining Tables
↳ Excel: Power Query → Merge Queries (or VLOOKUP/XLOOKUP)
↳ SQL: SELECT * FROM table1 JOIN table2 ON table1.id = table2.id;
↳ Python: df_merged = pd.merge(df1, df2, on="id")
6️⃣ Ranking Data
↳ Excel: =RANK.EQ(A2, $A$2:$A$100)
↳ SQL: SELECT column, RANK() OVER (ORDER BY column DESC) AS rank FROM table;
↳ Python: df["rank"] = df["column"].rank(method="min", ascending=False)
7️⃣ Moving Average Calculation
↳ Excel: =AVERAGE(B2:B4) (manually for rolling window)
↳ SQL: SELECT date, AVG(value) OVER (ORDER BY date ROWS BETWEEN 2 PRECEDING AND CURRENT ROW) AS moving_avg FROM table;
↳ Python: df["moving_avg"] = df["value"].rolling(window=3).mean()
8️⃣ Running Total
↳ Excel: =SUM($B$2:B2) (drag down)
↳ SQL: SELECT date, SUM(value) OVER (ORDER BY date) AS running_total FROM table;
↳ Python: df["running_total"] = df["value"].cumsum()
1️⃣ Filtering Data
↳ Excel: =FILTER(A2:D100, B2:B100>50) (Excel 365 users)
↳ SQL: SELECT * FROM table WHERE column > 50;
↳ Python: df_filtered = df[df['column'] > 50]
2️⃣ Sorting Data
↳ Excel: Data → Sort (or =SORT(A2:A100, 1, TRUE))
↳ SQL: SELECT * FROM table ORDER BY column ASC;
↳ Python: df_sorted = df.sort_values(by="column")
3️⃣ Counting Rows
↳ Excel: =COUNTA(A:A)
↳ SQL: SELECT COUNT(*) FROM table;
↳ Python: row_count = len(df)
4️⃣ Removing Duplicates
↳ Excel: Data → Remove Duplicates
↳ SQL: SELECT DISTINCT * FROM table;
↳ Python: df_unique = df.drop_duplicates()
5️⃣ Joining Tables
↳ Excel: Power Query → Merge Queries (or VLOOKUP/XLOOKUP)
↳ SQL: SELECT * FROM table1 JOIN table2 ON table1.id = table2.id;
↳ Python: df_merged = pd.merge(df1, df2, on="id")
6️⃣ Ranking Data
↳ Excel: =RANK.EQ(A2, $A$2:$A$100)
↳ SQL: SELECT column, RANK() OVER (ORDER BY column DESC) AS rank FROM table;
↳ Python: df["rank"] = df["column"].rank(method="min", ascending=False)
7️⃣ Moving Average Calculation
↳ Excel: =AVERAGE(B2:B4) (manually for rolling window)
↳ SQL: SELECT date, AVG(value) OVER (ORDER BY date ROWS BETWEEN 2 PRECEDING AND CURRENT ROW) AS moving_avg FROM table;
↳ Python: df["moving_avg"] = df["value"].rolling(window=3).mean()
8️⃣ Running Total
↳ Excel: =SUM($B$2:B2) (drag down)
↳ SQL: SELECT date, SUM(value) OVER (ORDER BY date) AS running_total FROM table;
↳ Python: df["running_total"] = df["value"].cumsum()
❤22👍1🔥1
How do analysts use SQL in a company?
SQL is every data analyst’s superpower! Here's how they use it in the real world:
Extract Data
Pull data from multiple tables to answer business questions.
Example:
(P.S. Avoid SELECT *—your future self (and the database) will thank you!)
Clean & Transform
Use SQL functions to clean raw data.
Think TRIM(), COALESCE(), CAST()—like giving data a fresh haircut.
Summarize & Analyze
Group and aggregate to spot trends and patterns.
GROUP BY, SUM(), AVG() – your best friends for quick insights.
Build Dashboards
Feed SQL queries into Power BI, Tableau, or Excel to create visual stories that make data talk.
Run A/B Tests
Evaluate product changes and campaigns by comparing user groups.
SQL makes sure your decisions are backed by data, not just gut feeling.
Use Views & CTEs
Simplify complex queries with Views and Common Table Expressions.
Clean, reusable, and boss-approved.
Drive Decisions
SQL powers decisions across Marketing, Product, Sales, and Finance.
When someone asks “What’s working?”—you’ve got the answers.
And remember: write smart queries, not lazy ones. Say no to SELECT * unless you really mean it!
Hit ♥️ if you want me to share more real-world examples to make data analytics easier to understand!
Share with credits: https://news.1rj.ru/str/sqlspecialist
Hope it helps :)
SQL is every data analyst’s superpower! Here's how they use it in the real world:
Extract Data
Pull data from multiple tables to answer business questions.
Example:
SELECT name, revenue FROM sales WHERE region = 'North America';
(P.S. Avoid SELECT *—your future self (and the database) will thank you!)
Clean & Transform
Use SQL functions to clean raw data.
Think TRIM(), COALESCE(), CAST()—like giving data a fresh haircut.
Summarize & Analyze
Group and aggregate to spot trends and patterns.
GROUP BY, SUM(), AVG() – your best friends for quick insights.
Build Dashboards
Feed SQL queries into Power BI, Tableau, or Excel to create visual stories that make data talk.
Run A/B Tests
Evaluate product changes and campaigns by comparing user groups.
SQL makes sure your decisions are backed by data, not just gut feeling.
Use Views & CTEs
Simplify complex queries with Views and Common Table Expressions.
Clean, reusable, and boss-approved.
Drive Decisions
SQL powers decisions across Marketing, Product, Sales, and Finance.
When someone asks “What’s working?”—you’ve got the answers.
And remember: write smart queries, not lazy ones. Say no to SELECT * unless you really mean it!
Hit ♥️ if you want me to share more real-world examples to make data analytics easier to understand!
Share with credits: https://news.1rj.ru/str/sqlspecialist
Hope it helps :)
❤8
Complete roadmap to learn Python for data analysis
Step 1: Fundamentals of Python
1. Basics of Python Programming
- Introduction to Python
- Data types (integers, floats, strings, booleans)
- Variables and constants
- Basic operators (arithmetic, comparison, logical)
2. Control Structures
- Conditional statements (if, elif, else)
- Loops (for, while)
- List comprehensions
3. Functions and Modules
- Defining functions
- Function arguments and return values
- Importing modules
- Built-in functions vs. user-defined functions
4. Data Structures
- Lists, tuples, sets, dictionaries
- Manipulating data structures (add, remove, update elements)
Step 2: Advanced Python
1. File Handling
- Reading from and writing to files
- Working with different file formats (txt, csv, json)
2. Error Handling
- Try, except blocks
- Handling exceptions and errors gracefully
3. Object-Oriented Programming (OOP)
- Classes and objects
- Inheritance and polymorphism
- Encapsulation
Step 3: Libraries for Data Analysis
1. NumPy
- Understanding arrays and array operations
- Indexing, slicing, and iterating
- Mathematical functions and statistical operations
2. Pandas
- Series and DataFrames
- Reading and writing data (csv, excel, sql, json)
- Data cleaning and preparation
- Merging, joining, and concatenating data
- Grouping and aggregating data
3. Matplotlib and Seaborn
- Data visualization with Matplotlib
- Plotting different types of graphs (line, bar, scatter, histogram)
- Customizing plots
- Advanced visualizations with Seaborn
Step 4: Data Manipulation and Analysis
1. Data Wrangling
- Handling missing values
- Data transformation
- Feature engineering
2. Exploratory Data Analysis (EDA)
- Denoscriptive statistics
- Data visualization techniques
- Identifying patterns and outliers
3. Statistical Analysis
- Hypothesis testing
- Correlation and regression analysis
- Probability distributions
Step 5: Advanced Topics
1. Time Series Analysis
- Working with datetime objects
- Time series decomposition
- Forecasting models
2. Machine Learning Basics
- Introduction to machine learning
- Supervised vs. unsupervised learning
- Using Scikit-Learn for machine learning
- Building and evaluating models
3. Big Data and Cloud Computing
- Introduction to big data frameworks (e.g., Hadoop, Spark)
- Using cloud services for data analysis (e.g., AWS, Google Cloud)
Step 6: Practical Projects
1. Hands-on Projects
- Analyzing datasets from Kaggle
- Building interactive dashboards with Plotly or Dash
- Developing end-to-end data analysis projects
2. Collaborative Projects
- Participating in data science competitions
- Contributing to open-source projects
👨💻 FREE Resources to Learn & Practice Python
1. https://www.freecodecamp.org/learn/data-analysis-with-python/#data-analysis-with-python-course
2. https://www.hackerrank.com/domains/python
3. https://www.hackerearth.com/practice/python/getting-started/numbers/practice-problems/
4. https://news.1rj.ru/str/PythonInterviews
5. https://www.w3schools.com/python/python_exercises.asp
6. https://news.1rj.ru/str/pythonfreebootcamp/134
7. https://news.1rj.ru/str/pythonanalyst
8. https://pythonbasics.org/exercises/
9. https://news.1rj.ru/str/pythondevelopersindia/300
10. https://www.geeksforgeeks.org/python-programming-language/learn-python-tutorial
11. https://news.1rj.ru/str/pythonspecialist/33
Join @free4unow_backup for more free resources
ENJOY LEARNING 👍👍
Step 1: Fundamentals of Python
1. Basics of Python Programming
- Introduction to Python
- Data types (integers, floats, strings, booleans)
- Variables and constants
- Basic operators (arithmetic, comparison, logical)
2. Control Structures
- Conditional statements (if, elif, else)
- Loops (for, while)
- List comprehensions
3. Functions and Modules
- Defining functions
- Function arguments and return values
- Importing modules
- Built-in functions vs. user-defined functions
4. Data Structures
- Lists, tuples, sets, dictionaries
- Manipulating data structures (add, remove, update elements)
Step 2: Advanced Python
1. File Handling
- Reading from and writing to files
- Working with different file formats (txt, csv, json)
2. Error Handling
- Try, except blocks
- Handling exceptions and errors gracefully
3. Object-Oriented Programming (OOP)
- Classes and objects
- Inheritance and polymorphism
- Encapsulation
Step 3: Libraries for Data Analysis
1. NumPy
- Understanding arrays and array operations
- Indexing, slicing, and iterating
- Mathematical functions and statistical operations
2. Pandas
- Series and DataFrames
- Reading and writing data (csv, excel, sql, json)
- Data cleaning and preparation
- Merging, joining, and concatenating data
- Grouping and aggregating data
3. Matplotlib and Seaborn
- Data visualization with Matplotlib
- Plotting different types of graphs (line, bar, scatter, histogram)
- Customizing plots
- Advanced visualizations with Seaborn
Step 4: Data Manipulation and Analysis
1. Data Wrangling
- Handling missing values
- Data transformation
- Feature engineering
2. Exploratory Data Analysis (EDA)
- Denoscriptive statistics
- Data visualization techniques
- Identifying patterns and outliers
3. Statistical Analysis
- Hypothesis testing
- Correlation and regression analysis
- Probability distributions
Step 5: Advanced Topics
1. Time Series Analysis
- Working with datetime objects
- Time series decomposition
- Forecasting models
2. Machine Learning Basics
- Introduction to machine learning
- Supervised vs. unsupervised learning
- Using Scikit-Learn for machine learning
- Building and evaluating models
3. Big Data and Cloud Computing
- Introduction to big data frameworks (e.g., Hadoop, Spark)
- Using cloud services for data analysis (e.g., AWS, Google Cloud)
Step 6: Practical Projects
1. Hands-on Projects
- Analyzing datasets from Kaggle
- Building interactive dashboards with Plotly or Dash
- Developing end-to-end data analysis projects
2. Collaborative Projects
- Participating in data science competitions
- Contributing to open-source projects
👨💻 FREE Resources to Learn & Practice Python
1. https://www.freecodecamp.org/learn/data-analysis-with-python/#data-analysis-with-python-course
2. https://www.hackerrank.com/domains/python
3. https://www.hackerearth.com/practice/python/getting-started/numbers/practice-problems/
4. https://news.1rj.ru/str/PythonInterviews
5. https://www.w3schools.com/python/python_exercises.asp
6. https://news.1rj.ru/str/pythonfreebootcamp/134
7. https://news.1rj.ru/str/pythonanalyst
8. https://pythonbasics.org/exercises/
9. https://news.1rj.ru/str/pythondevelopersindia/300
10. https://www.geeksforgeeks.org/python-programming-language/learn-python-tutorial
11. https://news.1rj.ru/str/pythonspecialist/33
Join @free4unow_backup for more free resources
ENJOY LEARNING 👍👍
❤9
SQL (Structured Query Language) is the universal language of databases. Whether you're analyzing sales data, optimizing marketing campaigns, or tracking user behavior, SQL is your go-to tool for:
✅ Accessing and managing data efficiently
✅ Writing queries to extract insights
✅ Building a strong foundation for advanced tools like Python, R, or Power BI
In short, SQL is the bridge between raw data and actionable insights. 🌉
SQL Topics to Learn for Data Analyst/Business Analyst Roles
1. Basic:
* SELECT statements
* WHERE clause
* JOINs (INNER, LEFT, RIGHT, FULL)
* GROUP BY and HAVING
* ORDER BY
* Basic Aggregate Functions (COUNT, SUM, AVG, MIN, MAX)
2. Intermediate:
* Subqueries
* CASE statements
* UNION and UNION ALL
* Common Table Expressions (CTEs)
* Window Functions (ROW_NUMBER, RANK, DENSE_RANK, OVER)
* Data Manipulation (INSERT, UPDATE, DELETE)
* Indexes and Performance Tuning
3. Advanced:
* Advanced Window Functions (LEAD, LAG, NTILE)
* Complex Subqueries and Correlated Subqueries
* Advanced Performance Tuning
SQL is not just a skill—it’s the foundation of your data career. 🌟
Here you can find essential SQL Interview Resources👇
https://whatsapp.com/channel/0029VanC5rODzgT6TiTGoa1v
Like this post if you need more 👍❤️
Hope it helps :)
✅ Accessing and managing data efficiently
✅ Writing queries to extract insights
✅ Building a strong foundation for advanced tools like Python, R, or Power BI
In short, SQL is the bridge between raw data and actionable insights. 🌉
SQL Topics to Learn for Data Analyst/Business Analyst Roles
1. Basic:
* SELECT statements
* WHERE clause
* JOINs (INNER, LEFT, RIGHT, FULL)
* GROUP BY and HAVING
* ORDER BY
* Basic Aggregate Functions (COUNT, SUM, AVG, MIN, MAX)
2. Intermediate:
* Subqueries
* CASE statements
* UNION and UNION ALL
* Common Table Expressions (CTEs)
* Window Functions (ROW_NUMBER, RANK, DENSE_RANK, OVER)
* Data Manipulation (INSERT, UPDATE, DELETE)
* Indexes and Performance Tuning
3. Advanced:
* Advanced Window Functions (LEAD, LAG, NTILE)
* Complex Subqueries and Correlated Subqueries
* Advanced Performance Tuning
SQL is not just a skill—it’s the foundation of your data career. 🌟
Here you can find essential SQL Interview Resources👇
https://whatsapp.com/channel/0029VanC5rODzgT6TiTGoa1v
Like this post if you need more 👍❤️
Hope it helps :)
❤7
Want to become a Data Scientist?
Here’s a quick roadmap with essential concepts:
1. Mathematics & Statistics
Linear Algebra: Matrix operations, eigenvalues, eigenvectors, and decomposition, which are crucial for machine learning.
Probability & Statistics: Hypothesis testing, probability distributions, Bayesian inference, confidence intervals, and statistical significance.
Calculus: Derivatives, integrals, and gradients, especially partial derivatives, which are essential for understanding model optimization.
2. Programming
Python or R: Choose a primary programming language for data science.
Python: Libraries like NumPy, Pandas for data manipulation, and Scikit-Learn for machine learning.
R: Especially popular in academia and finance, with libraries like dplyr and ggplot2 for data manipulation and visualization.
SQL: Master querying and database management, essential for accessing, joining, and filtering large datasets.
3. Data Wrangling & Preprocessing
Data Cleaning: Handle missing values, outliers, duplicates, and data formatting.
Feature Engineering: Create meaningful features, handle categorical variables, and apply transformations (scaling, encoding, etc.).
Exploratory Data Analysis (EDA): Visualize data distributions, correlations, and trends to generate hypotheses and insights.
4. Data Visualization
Python Libraries: Use Matplotlib, Seaborn, and Plotly to visualize data.
Tableau or Power BI: Learn interactive visualization tools for building dashboards.
Storytelling: Develop skills to interpret and present data in a meaningful way to stakeholders.
5. Machine Learning
Supervised Learning: Understand algorithms like Linear Regression, Logistic Regression, Decision Trees, Random Forest, Gradient Boosting, and Support Vector Machines (SVM).
Unsupervised Learning: Study clustering (K-means, DBSCAN) and dimensionality reduction (PCA, t-SNE).
Evaluation Metrics: Understand accuracy, precision, recall, F1-score for classification and RMSE, MAE for regression.
6. Advanced Machine Learning & Deep Learning
Neural Networks: Understand the basics of neural networks and backpropagation.
Deep Learning: Get familiar with Convolutional Neural Networks (CNNs) for image processing and Recurrent Neural Networks (RNNs) for sequential data.
Transfer Learning: Apply pre-trained models for specific use cases.
Frameworks: Use TensorFlow Keras for building deep learning models.
7. Natural Language Processing (NLP)
Text Preprocessing: Tokenization, stemming, lemmatization, stop-word removal.
NLP Techniques: Understand bag-of-words, TF-IDF, and word embeddings (Word2Vec, GloVe).
NLP Models: Work with recurrent neural networks (RNNs), transformers (BERT, GPT) for text classification, sentiment analysis, and translation.
8. Big Data Tools (Optional)
Distributed Data Processing: Learn Hadoop and Spark for handling large datasets. Use Google BigQuery for big data storage and processing.
9. Data Science Workflows & Pipelines (Optional)
ETL & Data Pipelines: Extract, Transform, and Load data using tools like Apache Airflow for automation. Set up reproducible workflows for data transformation, modeling, and monitoring.
Model Deployment: Deploy models in production using Flask, FastAPI, or cloud services (AWS SageMaker, Google AI Platform).
10. Model Validation & Tuning
Cross-Validation: Techniques like K-fold cross-validation to avoid overfitting.
Hyperparameter Tuning: Use Grid Search, Random Search, and Bayesian Optimization to optimize model performance.
Bias-Variance Trade-off: Understand how to balance bias and variance in models for better generalization.
11. Time Series Analysis
Statistical Models: ARIMA, SARIMA, and Holt-Winters for time-series forecasting.
Time Series: Handle seasonality, trends, and lags. Use LSTMs or Prophet for more advanced time-series forecasting.
12. Experimentation & A/B Testing
Experiment Design: Learn how to set up and analyze controlled experiments.
A/B Testing: Statistical techniques for comparing groups & measuring the impact of changes.
ENJOY LEARNING 👍👍
#datascience
Here’s a quick roadmap with essential concepts:
1. Mathematics & Statistics
Linear Algebra: Matrix operations, eigenvalues, eigenvectors, and decomposition, which are crucial for machine learning.
Probability & Statistics: Hypothesis testing, probability distributions, Bayesian inference, confidence intervals, and statistical significance.
Calculus: Derivatives, integrals, and gradients, especially partial derivatives, which are essential for understanding model optimization.
2. Programming
Python or R: Choose a primary programming language for data science.
Python: Libraries like NumPy, Pandas for data manipulation, and Scikit-Learn for machine learning.
R: Especially popular in academia and finance, with libraries like dplyr and ggplot2 for data manipulation and visualization.
SQL: Master querying and database management, essential for accessing, joining, and filtering large datasets.
3. Data Wrangling & Preprocessing
Data Cleaning: Handle missing values, outliers, duplicates, and data formatting.
Feature Engineering: Create meaningful features, handle categorical variables, and apply transformations (scaling, encoding, etc.).
Exploratory Data Analysis (EDA): Visualize data distributions, correlations, and trends to generate hypotheses and insights.
4. Data Visualization
Python Libraries: Use Matplotlib, Seaborn, and Plotly to visualize data.
Tableau or Power BI: Learn interactive visualization tools for building dashboards.
Storytelling: Develop skills to interpret and present data in a meaningful way to stakeholders.
5. Machine Learning
Supervised Learning: Understand algorithms like Linear Regression, Logistic Regression, Decision Trees, Random Forest, Gradient Boosting, and Support Vector Machines (SVM).
Unsupervised Learning: Study clustering (K-means, DBSCAN) and dimensionality reduction (PCA, t-SNE).
Evaluation Metrics: Understand accuracy, precision, recall, F1-score for classification and RMSE, MAE for regression.
6. Advanced Machine Learning & Deep Learning
Neural Networks: Understand the basics of neural networks and backpropagation.
Deep Learning: Get familiar with Convolutional Neural Networks (CNNs) for image processing and Recurrent Neural Networks (RNNs) for sequential data.
Transfer Learning: Apply pre-trained models for specific use cases.
Frameworks: Use TensorFlow Keras for building deep learning models.
7. Natural Language Processing (NLP)
Text Preprocessing: Tokenization, stemming, lemmatization, stop-word removal.
NLP Techniques: Understand bag-of-words, TF-IDF, and word embeddings (Word2Vec, GloVe).
NLP Models: Work with recurrent neural networks (RNNs), transformers (BERT, GPT) for text classification, sentiment analysis, and translation.
8. Big Data Tools (Optional)
Distributed Data Processing: Learn Hadoop and Spark for handling large datasets. Use Google BigQuery for big data storage and processing.
9. Data Science Workflows & Pipelines (Optional)
ETL & Data Pipelines: Extract, Transform, and Load data using tools like Apache Airflow for automation. Set up reproducible workflows for data transformation, modeling, and monitoring.
Model Deployment: Deploy models in production using Flask, FastAPI, or cloud services (AWS SageMaker, Google AI Platform).
10. Model Validation & Tuning
Cross-Validation: Techniques like K-fold cross-validation to avoid overfitting.
Hyperparameter Tuning: Use Grid Search, Random Search, and Bayesian Optimization to optimize model performance.
Bias-Variance Trade-off: Understand how to balance bias and variance in models for better generalization.
11. Time Series Analysis
Statistical Models: ARIMA, SARIMA, and Holt-Winters for time-series forecasting.
Time Series: Handle seasonality, trends, and lags. Use LSTMs or Prophet for more advanced time-series forecasting.
12. Experimentation & A/B Testing
Experiment Design: Learn how to set up and analyze controlled experiments.
A/B Testing: Statistical techniques for comparing groups & measuring the impact of changes.
ENJOY LEARNING 👍👍
#datascience
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