Data Analytics
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Learn SQL, Python, Alteryx, Tableau, Power BI and many more

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โœ… Data Analytics Roadmap for Freshers in 2025 ๐Ÿš€๐Ÿ“Š

1๏ธโƒฃ Understand What a Data Analyst Does
๐Ÿ” Analyze data, find insights, create dashboards, support business decisions.

2๏ธโƒฃ Start with Excel
๐Ÿ“ˆ Learn:
โ€“ Basic formulas
โ€“ Charts & Pivot Tables
โ€“ Data cleaning
๐Ÿ’ก Excel is still the #1 tool in many companies.

3๏ธโƒฃ Learn SQL
๐Ÿงฉ SQL helps you pull and analyze data from databases.
Start with:
โ€“ SELECT, WHERE, JOIN, GROUP BY
๐Ÿ› ๏ธ Practice on platforms like W3Schools or Mode Analytics.

4๏ธโƒฃ Pick a Programming Language
๐Ÿ Start with Python (easier) or R
โ€“ Learn pandas, matplotlib, numpy
โ€“ Do small projects (e.g. analyze sales data)

5๏ธโƒฃ Data Visualization Tools
๐Ÿ“Š Learn:
โ€“ Power BI or Tableau
โ€“ Build simple dashboards
๐Ÿ’ก Start with free versions or YouTube tutorials.

6๏ธโƒฃ Practice with Real Data
๐Ÿ” Use sites like Kaggle or Data.gov
โ€“ Clean, analyze, visualize
โ€“ Try small case studies (sales report, customer trends)

7๏ธโƒฃ Create a Portfolio
๐Ÿ’ป Share projects on:
โ€“ GitHub
โ€“ Notion or a simple website
๐Ÿ“Œ Add visuals + brief explanations of your insights.

8๏ธโƒฃ Improve Soft Skills
๐Ÿ—ฃ๏ธ Focus on:
โ€“ Presenting data in simple words
โ€“ Asking good questions
โ€“ Thinking critically about patterns

9๏ธโƒฃ Certifications to Stand Out
๐ŸŽ“ Try:
โ€“ Google Data Analytics (Coursera)
โ€“ IBM Data Analyst
โ€“ LinkedIn Learning basics

๐Ÿ”Ÿ Apply for Internships & Entry Jobs
๐ŸŽฏ Titles to look for:
โ€“ Data Analyst (Intern)
โ€“ Junior Analyst
โ€“ Business Analyst

๐Ÿ’ฌ React โค๏ธ for more!
โค14๐Ÿ‘2
๐Ÿš€ Excel vs SQL vs Python (Pandas):

1๏ธโƒฃ Filtering Data
โ†ณ Excel: =FILTER(A2:D100, B2:B100>50) (Excel 365 users)
โ†ณ SQL: SELECT * FROM table WHERE column > 50;
โ†ณ Python: df_filtered = df[df['column'] > 50]

2๏ธโƒฃ Sorting Data
โ†ณ Excel: Data โ†’ Sort (or =SORT(A2:A100, 1, TRUE))
โ†ณ SQL: SELECT * FROM table ORDER BY column ASC;
โ†ณ Python: df_sorted = df.sort_values(by="column")

3๏ธโƒฃ Counting Rows
โ†ณ Excel: =COUNTA(A:A)
โ†ณ SQL: SELECT COUNT(*) FROM table;
โ†ณ Python: row_count = len(df)

4๏ธโƒฃ Removing Duplicates
โ†ณ Excel: Data โ†’ Remove Duplicates
โ†ณ SQL: SELECT DISTINCT * FROM table;
โ†ณ Python: df_unique = df.drop_duplicates()

5๏ธโƒฃ Joining Tables
โ†ณ Excel: Power Query โ†’ Merge Queries (or VLOOKUP/XLOOKUP)
โ†ณ SQL: SELECT * FROM table1 JOIN table2 ON table1.id = table2.id;
โ†ณ Python: df_merged = pd.merge(df1, df2, on="id")

6๏ธโƒฃ Ranking Data
โ†ณ Excel: =RANK.EQ(A2, $A$2:$A$100)
โ†ณ SQL: SELECT column, RANK() OVER (ORDER BY column DESC) AS rank FROM table;
โ†ณ Python: df["rank"] = df["column"].rank(method="min", ascending=False)

7๏ธโƒฃ Moving Average Calculation
โ†ณ Excel: =AVERAGE(B2:B4) (manually for rolling window)
โ†ณ SQL: SELECT date, AVG(value) OVER (ORDER BY date ROWS BETWEEN 2 PRECEDING AND CURRENT ROW) AS moving_avg FROM table;
โ†ณ Python: df["moving_avg"] = df["value"].rolling(window=3).mean()

8๏ธโƒฃ Running Total
โ†ณ Excel: =SUM($B$2:B2) (drag down)
โ†ณ SQL: SELECT date, SUM(value) OVER (ORDER BY date) AS running_total FROM table;
โ†ณ Python: df["running_total"] = df["value"].cumsum()
โค23๐Ÿ‘1๐Ÿ”ฅ1
How do analysts use SQL in a company?

SQL is every data analystโ€™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 *โ€”your future self (and the database) will thank you!)


Clean & Transform

Use SQL functions to clean raw data.

Think TRIM(), COALESCE(), CAST()โ€”like giving data a fresh haircut.


Summarize & Analyze

Group and aggregate to spot trends and patterns.

GROUP BY, SUM(), AVG() โ€“ 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 โ€œWhatโ€™s working?โ€โ€”youโ€™ve got the answers.


And remember: write smart queries, not lazy ones. Say no to SELECT * unless you really mean it!

Hit โ™ฅ๏ธ if you want me to share more real-world examples to make data analytics easier to understand!

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Hope it helps :)
โค8
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)
- Descriptive 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

๐Ÿ‘จโ€๐Ÿ’ป 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://t.iss.one/PythonInterviews
5. https://www.w3schools.com/python/python_exercises.asp
6. https://t.iss.one/pythonfreebootcamp/134
7. https://t.iss.one/pythonanalyst
8. https://pythonbasics.org/exercises/
9. https://t.iss.one/pythondevelopersindia/300
10. https://www.geeksforgeeks.org/python-programming-language/learn-python-tutorial
11. https://t.iss.one/pythonspecialist/33

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โค10
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:

โœ… Accessing and managing data efficiently
โœ… Writing queries to extract insights
โœ… 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. ๐ŸŒ‰

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 skillโ€”itโ€™s the foundation of your data career. ๐ŸŒŸ

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โค7
Want to become a Data Scientist?

Hereโ€™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 ๐Ÿ‘๐Ÿ‘

#datascience
โค10
Essential Python and SQL topics for data analysts ๐Ÿ˜„๐Ÿ‘‡

Python Topics:

1. Data Structures
   - Lists, Tuples, and Dictionaries
   - NumPy Arrays for numerical data

2. Data Manipulation
   - Pandas DataFrames for structured data
   - Data Cleaning and Preprocessing techniques
   - Data Transformation and Reshaping

3. Data Visualization
   - Matplotlib for basic plotting
   - Seaborn for statistical visualizations
   - Plotly for interactive charts

4. Statistical Analysis
   - Descriptive Statistics
   - Hypothesis Testing
   - Regression Analysis

5. Machine Learning
   - Scikit-Learn for machine learning models
   - Model Building, Training, and Evaluation
   - Feature Engineering and Selection

6. Time Series Analysis
   - Handling Time Series Data
   - Time Series Forecasting
   - Anomaly Detection

7. Python Fundamentals
   - Control Flow (if statements, loops)
   - Functions and Modular Code
   - Exception Handling
   - File

SQL Topics:

1. SQL Basics
- SQL Syntax
- SELECT Queries
- Filters

2. Data Retrieval
- Aggregation Functions (SUM, AVG, COUNT)
- GROUP BY

3. Data Filtering
- WHERE Clause
- ORDER BY

4. Data Joins
- JOIN Operations
- Subqueries

5. Advanced SQL
- Window Functions
- Indexing
- Performance Optimization

6. Database Management
- Connecting to Databases
- SQLAlchemy

7. Database Design
- Data Types
- Normalization

Remember, it's highly likely that you won't know all these concepts from the start. Data analysis is a journey where the more you learn, the more you grow. Embrace the learning process, and your skills will continually evolve and expand. Keep up the great work!

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โค4
Complete step-by-step syllabus of #Excel for Data Analytics

Introduction to Excel for Data Analytics:
Overview of Excel's capabilities for data analysis
Introduction to Excel's interface: ribbons, worksheets, cells, etc.
Differences between Excel desktop version and Excel Online (web version)

Data Import and Preparation:
Importing data from various sources: CSV, text files, databases, web queries, etc.
Data cleaning and manipulation techniques: sorting, filtering, removing duplicates, etc.
Data types and formatting in Excel
Data validation and error handling

Data Analysis Techniques in Excel:
Basic formulas and functions: SUM, AVERAGE, COUNT, IF, VLOOKUP, etc.
Advanced functions for data analysis: INDEX-MATCH, SUMIFS, COUNTIFS, etc.
PivotTables and PivotCharts for summarizing and analyzing data
Advanced data analysis tools: Goal Seek, Solver, What-If Analysis, etc.

Data Visualization in Excel:
Creating basic charts: column, bar, line, pie, scatter, etc.
Formatting and customizing charts for better visualization
Using sparklines for visualizing trends in data
Creating interactive dashboards with slicers and timelines

Advanced Data Analysis Features:
Data modeling with Excel Tables and Relationships
Using Power Query for data transformation and cleaning
Introduction to Power Pivot for data modeling and DAX calculations
Advanced charting techniques: combination charts, waterfall charts, etc.

Statistical Analysis in Excel:
Descriptive statistics: mean, median, mode, standard deviation, etc.
Hypothesis testing: t-tests, chi-square tests, ANOVA, etc.
Regression analysis and correlation
Forecasting techniques: moving averages, exponential smoothing, etc.

Data Visualization Tools in Excel:
Introduction to Excel add-ins for enhanced visualization (e.g., Power Map, Power View)
Creating interactive reports with Excel add-ins
Introduction to Excel Data Model for handling large datasets

Real-world Projects and Case Studies:
Analyzing real-world datasets
Solving business problems with Excel
Portfolio development showcasing Excel skills

Free Resources: https://t.iss.one/excel_data

Hope this helps you ๐Ÿ˜Š
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SQL can be simpleโ€”if you learn it the smart way..



If youโ€™re aiming to become a data analyst, mastering SQL is non-negotiable.
Hereโ€™s a smart roadmap to ace it:

1. Basics First: Understand data types, simple queries (SELECT, FROM, WHERE). Master basic filtering.

2. Joins & Relationships: Dive into INNER, LEFT, RIGHT joins. Practice combining tables to extract meaningful insights.

3. Aggregations & Functions: Get comfortable with COUNT, SUM, AVG, MAX, GROUP BY, and HAVING clauses. These are essential for summarizing data.

4. Subqueries & Nested Queries: Learn how to query within queries. This is powerful for handling complex datasets.

5. Window Functions: Explore ranking, cumulative sums, and sliding windows to work with running totals and moving averages.

6. Optimization: Study indexing and query optimization for faster, more efficient queries.

7. Real-World Scenarios: Apply your SQL knowledge to solve real-world business problems.

The journey may seem tough, but each step sharpens your skills and brings you closer to data analysis excellence. Stay consistent, practice regularly, and let SQL become your superpower! ๐Ÿ’ช

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โค10
Quick SQL functions cheat sheet for beginners

Aggregate Functions

COUNT(*): Counts rows.

SUM(column): Total sum.

AVG(column): Average value.

MAX(column): Maximum value.

MIN(column): Minimum value.


String Functions

CONCAT(a, b, โ€ฆ): Concatenates strings.

SUBSTRING(s, start, length): Extracts part of a string.

UPPER(s) / LOWER(s): Converts string case.

TRIM(s): Removes leading/trailing spaces.


Date & Time Functions

CURRENT_DATE / CURRENT_TIME / CURRENT_TIMESTAMP: Current date/time.

EXTRACT(unit FROM date): Retrieves a date part (e.g., year, month).

DATE_ADD(date, INTERVAL n unit): Adds an interval to a date.


Numeric Functions

ROUND(num, decimals): Rounds to a specified decimal.

CEIL(num) / FLOOR(num): Rounds up/down.

ABS(num): Absolute value.

MOD(a, b): Returns the remainder.


Control Flow Functions

CASE: Conditional logic.

COALESCE(val1, val2, โ€ฆ): Returns the first non-null value.


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#dataanalytics
โค14
SQL Interview Questions with Answers

1. How to change a table name in SQL?
This is the command to change a table name in SQL:
ALTER TABLE table_name
RENAME TO new_table_name;
We will start off by giving the keywords ALTER TABLE, then we will follow it up by giving the original name of the table, after that, we will give in the keywords RENAME TO and finally, we will give the new table name.

2. How to use LIKE in SQL?
The LIKE operator checks if an attribute value matches a given string pattern. Here is an example of LIKE operator
SELECT * FROM employees WHERE first_name like โ€˜Stevenโ€™;
With this command, we will be able to extract all the records where the first name is like โ€œStevenโ€.

3. If we drop a table, does it also drop related objects like constraints, indexes, columns, default, views and sorted procedures?
Yes, SQL server drops all related objects, which exists inside a table like constraints, indexes, columns, defaults etc. But dropping a table will not drop views and sorted procedures as they exist outside the table.

4. Explain SQL Constraints.
SQL Constraints are used to specify the rules of data type in a table. They can be specified while creating and altering the table. The following are the constraints in SQL: NOT NULL CHECK DEFAULT UNIQUE PRIMARY KEY FOREIGN KEY

React โค๏ธ for more
โค8๐Ÿ‘Œ2
๐Ÿš€ Excel vs SQL vs Python (Pandas):

1๏ธโƒฃ Filtering Data
โ†ณ Excel: =FILTER(A2:D100, B2:B100>50) (Excel 365 users)
โ†ณ SQL: SELECT * FROM table WHERE column > 50;
โ†ณ Python: df_filtered = df[df['column'] > 50]

2๏ธโƒฃ Sorting Data
โ†ณ Excel: Data โ†’ Sort (or =SORT(A2:A100, 1, TRUE))
โ†ณ SQL: SELECT * FROM table ORDER BY column ASC;
โ†ณ Python: df_sorted = df.sort_values(by="column")

3๏ธโƒฃ Counting Rows
โ†ณ Excel: =COUNTA(A:A)
โ†ณ SQL: SELECT COUNT(*) FROM table;
โ†ณ Python: row_count = len(df)

4๏ธโƒฃ Removing Duplicates
โ†ณ Excel: Data โ†’ Remove Duplicates
โ†ณ SQL: SELECT DISTINCT * FROM table;
โ†ณ Python: df_unique = df.drop_duplicates()

5๏ธโƒฃ Joining Tables
โ†ณ Excel: Power Query โ†’ Merge Queries (or VLOOKUP/XLOOKUP)
โ†ณ SQL: SELECT * FROM table1 JOIN table2 ON table1.id = table2.id;
โ†ณ Python: df_merged = pd.merge(df1, df2, on="id")

6๏ธโƒฃ Ranking Data
โ†ณ Excel: =RANK.EQ(A2, $A$2:$A$100)
โ†ณ SQL: SELECT column, RANK() OVER (ORDER BY column DESC) AS rank FROM table;
โ†ณ Python: df["rank"] = df["column"].rank(method="min", ascending=False)

7๏ธโƒฃ Moving Average Calculation
โ†ณ Excel: =AVERAGE(B2:B4) (manually for rolling window)
โ†ณ SQL: SELECT date, AVG(value) OVER (ORDER BY date ROWS BETWEEN 2 PRECEDING AND CURRENT ROW) AS moving_avg FROM table;
โ†ณ Python: df["moving_avg"] = df["value"].rolling(window=3).mean()

8๏ธโƒฃ Running Total
โ†ณ Excel: =SUM($B$2:B2) (drag down)
โ†ณ SQL: SELECT date, SUM(value) OVER (ORDER BY date) AS running_total FROM table;
โ†ณ Python: df["running_total"] = df["value"].cumsum()
โค8๐Ÿ‘1
9 tips to get started with Data Analysis:

Learn Excel, SQL, and a programming language (Python or R)

Understand basic statistics and probability

Practice with real-world datasets (Kaggle, Data.gov)

Clean and preprocess data effectively

Visualize data using charts and graphs

Ask the right questions before diving into data

Use libraries like Pandas, NumPy, and Matplotlib

Focus on storytelling with data insights

Build small projects to apply what you learn

Data Science & Machine Learning Resources: https://whatsapp.com/channel/0029Va8v3eo1NCrQfGMseL2D

ENJOY LEARNING ๐Ÿ‘๐Ÿ‘
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SQL Joins Simplified โœ…
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SQL Zero to Hero โœ…
โค8๐Ÿ‘7๐Ÿ˜1
Commonly used Power BI DAX functions:

DATE AND TIME FUNCTIONS:
- CALENDAR
- DATEDIFF
- TODAY, DAY, MONTH, QUARTER, YEAR

AGGREGATE FUNCTIONS:
- SUM, SUMX, PRODUCT
- AVERAGE
- MIN, MAX
- COUNT
- COUNTROWS
- COUNTBLANK
- DISTINCTCOUNT

FILTER FUNCTIONS:
- CALCULATE
- FILTER
- ALL, ALLEXCEPT, ALLSELECTED, REMOVEFILTERS
- SELECTEDVALUE

TIME INTELLIGENCE FUNCTIONS:
- DATESBETWEEN
- DATESMTD, DATESQTD, DATESYTD
- SAMEPERIODLASTYEAR
- PARALLELPERIOD
- TOTALMTD, TOTALQTD, TOTALYTD

TEXT FUNCTIONS:
- CONCATENATE
- FORMAT
- LEN, LEFT, RIGHT

INFORMATION FUNCTIONS:
- HASONEVALUE, HASONEFILTER
- ISBLANK, ISERROR, ISEMPTY
- CONTAINS

LOGICAL FUNCTIONS:
- AND, OR, IF, NOT
- TRUE, FALSE
- SWITCH

RELATIONSHIP FUNCTIONS:
- RELATED
- USERRELATIONSHIP
- RELATEDTABLE

Remember, DAX is more about logic than the formulas.
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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 ๐Ÿ‘‡

โœ… They document every step of their analysis
โž Clear notes make their work reproducible and trustworthy.

โœ… They check data quality before the analysis begins
โž Garbage in = garbage out. Always validate first.

โœ… They use version control religiously
โž Every code change is tracked. Nothing gets lost.

โœ… They explore data thoroughly before diving in
โž Understanding context prevents costly misinterpretations.

โœ… They create automated scripts for repetitive tasks
โž Efficiency isnโ€™t a luxuryโ€”itโ€™s a necessity.

โœ… They maintain a reusable code library
โž Smart analysts never solve the same problem twice.

โœ… They test assumptions with multiple validation methods
โž One test isnโ€™t enough; they triangulate confidence.

โœ… They organize project files logically
โž Their work is navigable by anyone, not just themselves.

โœ… They seek peer reviews on critical work
โž Fresh eyes catch blind spots.

โœ… They continuously absorb industry knowledge
โž Learning never stops. Trends change too quickly.

โœ… They prioritize business-impacting projects
โž Every analysis must drive real decisions.

โœ… They explain complex findings simply
โž Technical brilliance is useless without clarity.

โœ… They write readable, well-commented code
โž Their work is accessible to others, long after they're gone.

โœ… They maintain robust backup systems
โž Data loss is never an option.

โœ… They learn from analytical mistakes
โž Errors become stepping stones, not roadblocks.

โœ… They build strong stakeholder relationships
โž Data is only valuable when people use it.

โœ… They break complex projects into manageable chunks
โž Progress happens through disciplined, incremental work.

โœ… They handle sensitive data with proper security
โž Compliance isnโ€™t optionalโ€”itโ€™s foundational.

โœ… They create visualizations that tell clear stories
โž A chart without a narrative is just decoration.

โœ… They actively seek evidence against their conclusions
โž Confirmation bias is their biggest enemy.

The best analysts arenโ€™t the ones with the most toolsโ€”theyโ€™re the ones with the most rigorous practices.
โค11
If youโ€™re a Data Analyst, chances are you use ๐’๐๐‹ every single day. And if youโ€™re preparing for interviews, youโ€™ve probably realized that it's not just about writing queries it's about writing smart, efficient, and scalable ones.

1. ๐๐ซ๐ž๐š๐ค ๐ˆ๐ญ ๐ƒ๐จ๐ฐ๐ง ๐ฐ๐ข๐ญ๐ก ๐‚๐“๐„๐ฌ (๐‚๐จ๐ฆ๐ฆ๐จ๐ง ๐“๐š๐›๐ฅ๐ž ๐„๐ฑ๐ฉ๐ซ๐ž๐ฌ๐ฌ๐ข๐จ๐ง๐ฌ)

Ever worked on a query that became an unreadable monster? CTEs let you break that down into logical steps. You can treat them like temporary views โ€” great for simplifying logic and improving collaboration across your team.

2. ๐”๐ฌ๐ž ๐–๐ข๐ง๐๐จ๐ฐ ๐…๐ฎ๐ง๐œ๐ญ๐ข๐จ๐ง๐ฌ

Forget the mess of subqueries. With functions like ROW_NUMBER(), RANK(), LEAD() and LAG(), you can compare rows, rank items, or calculate running totals โ€” all within the same query. Total

3. ๐’๐ฎ๐›๐ช๐ฎ๐ž๐ซ๐ข๐ž๐ฌ (๐๐ž๐ฌ๐ญ๐ž๐ ๐๐ฎ๐ž๐ซ๐ข๐ž๐ฌ)

Yes, they're old school, but nested subqueries are still powerful. Use them when you want to filter based on results of another query or isolate logic step-by-step before joining with the big picture.

4. ๐ˆ๐ง๐๐ž๐ฑ๐ž๐ฌ & ๐๐ฎ๐ž๐ซ๐ฒ ๐Ž๐ฉ๐ญ๐ข๐ฆ๐ข๐ณ๐š๐ญ๐ข๐จ๐ง

Query taking forever? Look at your indexes. Index the columns you use in JOINs, WHERE, and GROUP BY. Even basic knowledge of how the SQL engine reads data can take your skills up a notch.

5. ๐‰๐จ๐ข๐ง๐ฌ ๐ฏ๐ฌ. ๐’๐ฎ๐›๐ช๐ฎ๐ž๐ซ๐ข๐ž๐ฌ

Joins are usually faster and better for combining large datasets. Subqueries, on the other hand, are cleaner when doing one-off filters or smaller operations. Choose wisely based on the context.

6. ๐‚๐€๐’๐„ ๐’๐ญ๐š๐ญ๐ž๐ฆ๐ž๐ง๐ญ๐ฌ:

Want to categorize or bucket data without creating a separate table? Use CASE. Itโ€™s ideal for conditional logic, custom labels, and grouping in a single query.

7. ๐€๐ ๐ ๐ซ๐ž๐ ๐š๐ญ๐ข๐จ๐ง๐ฌ & ๐†๐‘๐Ž๐”๐ ๐๐˜

Most analytics questions start with "how many", "whatโ€™s the average", or "which is the highest?". SUM(), COUNT(), AVG(), etc., and pair them with GROUP BY to drive insights that matter.

8. ๐ƒ๐š๐ญ๐ž๐ฌ ๐€๐ซ๐ž ๐€๐ฅ๐ฐ๐š๐ฒ๐ฌ ๐“๐ซ๐ข๐œ๐ค๐ฒ

Time-based analysis is everywhere: trends, cohorts, seasonality, etc. Get familiar with functions like DATEADD, DATEDIFF, DATE_TRUNC, and DATEPART to work confidently with time series data.

9. ๐’๐ž๐ฅ๐Ÿ-๐‰๐จ๐ข๐ง๐ฌ & ๐‘๐ž๐œ๐ฎ๐ซ๐ฌ๐ข๐ฏ๐ž ๐๐ฎ๐ž๐ซ๐ข๐ž๐ฌ ๐Ÿ๐จ๐ซ ๐‡๐ข๐ž๐ซ๐š๐ซ๐œ๐ก๐ข๐ž๐ฌ

Whether it's org charts or product categories, not all data is flat. Learn how to join a table to itself or use recursive CTEs to navigate parent-child relationships effectively.


You donโ€™t need to memorize 100 functions. You need to understand 10 really well and apply them smartly. These are the concepts I keep going back to not just in interviews, but in the real world where clarity, performance, and logic matter most.
โค6๐Ÿ‘6
Essential Skills Excel for Data Analysts ๐Ÿš€

1๏ธโƒฃ Data Cleaning & Transformation

Remove Duplicates โ€“ Ensure unique records.
Find & Replace โ€“ Quick data modifications.
Text Functions โ€“ TRIM, LEN, LEFT, RIGHT, MID, PROPER.
Data Validation โ€“ Restrict input values.

2๏ธโƒฃ Data Analysis & Manipulation

Sorting & Filtering โ€“ Organize and extract key insights.
Conditional Formatting โ€“ Highlight trends, outliers.
Pivot Tables โ€“ Summarize large datasets efficiently.
Power Query โ€“ Automate data transformation.

3๏ธโƒฃ Essential Formulas & Functions

Lookup Functions โ€“ VLOOKUP, HLOOKUP, XLOOKUP, INDEX-MATCH.
Logical Functions โ€“ IF, AND, OR, IFERROR, IFS.
Aggregation Functions โ€“ SUM, AVERAGE, MIN, MAX, COUNT, COUNTA.
Text Functions โ€“ CONCATENATE, TEXTJOIN, SUBSTITUTE.

4๏ธโƒฃ Data Visualization
Charts & Graphs โ€“ Bar, Line, Pie, Scatter, Histogram.

Sparklines โ€“ Miniature charts inside cells.
Conditional Formatting โ€“ Color scales, data bars.
Dashboard Creation โ€“ Interactive and dynamic reports.

5๏ธโƒฃ Advanced Excel Techniques
Array Formulas โ€“ Dynamic calculations with multiple values.
Power Pivot & DAX โ€“ Advanced data modeling.
What-If Analysis โ€“ Goal Seek, Scenario Manager.
Macros & VBA โ€“ Automate repetitive tasks.

6๏ธโƒฃ Data Import & Export
CSV & TXT Files โ€“ Import and clean raw data.
Power Query โ€“ Connect to databases, web sources.
Exporting Reports โ€“ PDF, CSV, Excel formats.

Here you can find some free Excel books & useful resources: https://t.iss.one/excel_data

Hope it helps :)

#dataanalyst
โค10
๐‡๐จ๐ฐ ๐ญ๐จ ๐๐ซ๐ž๐ฉ๐š๐ซ๐ž ๐ญ๐จ ๐๐ž๐œ๐จ๐ฆ๐ž ๐š ๐ƒ๐š๐ญ๐š ๐€๐ง๐š๐ฅ๐ฒ๐ฌ๐ญ

๐Ÿ. ๐„๐ฑ๐œ๐ž๐ฅ- Learn formulas, Pivot tables, Lookup, VBA Macros.

๐Ÿ. ๐’๐๐‹- Joins, Windows, CTE is the most important

๐Ÿ‘. ๐๐จ๐ฐ๐ž๐ซ ๐๐ˆ- Power Query Editor(PQE), DAX, MCode, RLS

๐Ÿ’. ๐๐ฒ๐ญ๐ก๐จ๐ง- Basics & Libraries(mainly pandas, numpy, matplotlib and seaborn libraries)

5. Practice SQL and Python questions on platforms like ๐‡๐š๐œ๐ค๐ž๐ซ๐‘๐š๐ง๐ค or ๐–๐Ÿ‘๐’๐œ๐ก๐จ๐จ๐ฅ๐ฌ.

6. Know the basics of descriptive statistics(mean, median, mode, Probability, normal, binomial, Poisson distributions etc).

7. Learn to use ๐€๐ˆ/๐‚๐จ๐ฉ๐ข๐ฅ๐จ๐ญ ๐ญ๐จ๐จ๐ฅ๐ฌ like GitHub Copilot or Power BI's AI features to automate tasks, generate insights, and improve your projects(Most demanding in Companies now)

8. Get hands-on experience with one cloud platform: ๐€๐ณ๐ฎ๐ซ๐ž, ๐€๐–๐’, ๐จ๐ซ ๐†๐‚๐

9. Work on at least two end-to-end projects.

10. Prepare an ATS-friendly resume and start applying for jobs.

11. Prepare for interviews by going through common interview questions on Google and YouTube.

I have curated top-notch Data Analytics Resources ๐Ÿ‘‡๐Ÿ‘‡
https://whatsapp.com/channel/0029VaGgzAk72WTmQFERKh02

Hope this helps you ๐Ÿ˜Š
โค6