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Soft skills questions will be part of your next data job interview!

Here is what you should prepare for:

1. ๐—–๐—ผ๐—บ๐—บ๐˜‚๐—ป๐—ถ๐—ฐ๐—ฎ๐˜๐—ถ๐—ผ๐—ป: Be ready to discuss how you explain complex data insights to non-technical stakeholders.

๐˜Œ๐˜น๐˜ข๐˜ฎ๐˜ฑ๐˜ญ๐˜ฆ ๐˜ฒ๐˜ถ๐˜ฆ๐˜ด๐˜ต๐˜ช๐˜ฐ๐˜ฏ:
โ€œHow do you ensure that your data insights are understood and get used by non-technical stakeholders?โ€

2. ๐—ง๐—ฒ๐—ฎ๐—บ ๐—–๐—ผ๐—น๐—น๐—ฎ๐—ฏ๐—ผ๐—ฟ๐—ฎ๐˜๐—ถ๐—ผ๐—ป: Show your ability to work well with others.

๐˜Œ๐˜น๐˜ข๐˜ฎ๐˜ฑ๐˜ญ๐˜ฆ ๐˜ฒ๐˜ถ๐˜ฆ๐˜ด๐˜ต๐˜ช๐˜ฐ๐˜ฏ:
โ€œCan you talk about a time when you had to manage a conflict within a team? How did you resolve it?โ€

3. ๐—ฃ๐—ฟ๐—ผ๐—ฏ๐—น๐—ฒ๐—บ-๐—ฆ๐—ผ๐—น๐˜ƒ๐—ถ๐—ป๐—ด: Highlight your critical thinking and problem-solving skills.

๐˜Œ๐˜น๐˜ข๐˜ฎ๐˜ฑ๐˜ญ๐˜ฆ ๐˜ฒ๐˜ถ๐˜ฆ๐˜ด๐˜ต๐˜ช๐˜ฐ๐˜ฏ:
โ€œDescribe a situation where you had to make a quick decision based on incomplete data. What was the outcome?โ€

4. ๐—”๐—ฑ๐—ฎ๐—ฝ๐˜๐—ฎ๐—ฏ๐—ถ๐—น๐—ถ๐˜๐˜†: Demonstrate your flexibility and openness to change.

๐˜Œ๐˜น๐˜ข๐˜ฎ๐˜ฑ๐˜ญ๐˜ฆ ๐˜ฒ๐˜ถ๐˜ฆ๐˜ด๐˜ต๐˜ช๐˜ฐ๐˜ฏ:
โ€œHow do you handle sudden changes in project priorities or scope?โ€

5. ๐—ง๐—ถ๐—บ๐—ฒ ๐— ๐—ฎ๐—ป๐—ฎ๐—ด๐—ฒ๐—บ๐—ฒ๐—ป๐˜: Prove your ability to manage multiple tasks and deadlines.

๐˜Œ๐˜น๐˜ข๐˜ฎ๐˜ฑ๐˜ญ๐˜ฆ ๐˜ฒ๐˜ถ๐˜ฆ๐˜ด๐˜ต๐˜ช๐˜ฐ๐˜ฏ:
โ€œTell me about a time when you were under tight deadlines. How did you manage to meet them?โ€

6. ๐—˜๐—บ๐—ฝ๐—ฎ๐˜๐—ต๐˜† ๐—ฎ๐—ป๐—ฑ ๐—จ๐—ป๐—ฑ๐—ฒ๐—ฟ๐˜€๐˜๐—ฎ๐—ป๐—ฑ๐—ถ๐—ป๐—ด: Show your ability to understand stakeholder needs.

๐˜Œ๐˜น๐˜ข๐˜ฎ๐˜ฑ๐˜ญ๐˜ฆ ๐˜ฒ๐˜ถ๐˜ฆ๐˜ด๐˜ต๐˜ช๐˜ฐ๐˜ฏ:
โ€œHow do you approach understanding the needs of different stakeholders when starting a new project?โ€


Structure your answers using the STAR method (Situation, Task, Action, Result). This helps you provide clear and concise responses that highlight your skills.

By preparing for these soft skills questions, youโ€™ll demonstrate that youโ€™re not just technically fit, but also a well-rounded professional ready to make an impact on the business.

You can find useful tips to improve your soft skills here: ๐Ÿ‘‡ https://t.me/englishlearnerspro/
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๐Ÿš€ Data Science Roadmap 2026

**

๐Ÿ“ Phase 3: SQL for Data Science**

๐Ÿ“– Topic 2: SQL Basics โ€” WHERE

After learning SELECT, the next essential SQL concept is WHERE.

In real-world Data Science, databases can contain millions or billions of records. You usually don't want to retrieve everything.

You want to answer questions such as:

Which customers are from Mumbai?

Which orders are above โ‚น10,000?

Which employees joined after 2023?

Which transactions were successful?

Which products belong to a particular category?

The WHERE clause allows you to filter rows based on conditions.

๐Ÿ”น 1. What Is WHERE?

WHERE is used to filter records based on a specified condition.

Basic syntax:

SELECT column1, column2
FROM table_name
WHERE condition;


Example:

SELECT *
FROM customers
WHERE city = 'Mumbai';


This returns only customers whose city is Mumbai.

๐Ÿ”น 2. WHERE with Text Values

Text values are generally written inside single quotes.

Example:

SELECT customer_id, name
FROM customers
WHERE city = 'Pune';


This retrieves customers from Pune.

Another example:

SELECT *
FROM employees
WHERE department = 'Finance';


๐Ÿ”น 3. WHERE with Numbers

For numeric values, quotes are generally not required.

Example:

SELECT *
FROM customers
WHERE age > 30;


This returns customers older than 30.

Another example:

SELECT *
FROM orders
WHERE amount > 10000;


This returns orders where the amount is greater than 10,000.

๐Ÿ”น 4. Comparison Operators

The most commonly used comparison operators are:

Operator Meaning

= Equal to

<> Not equal to

!= Not equal to



Greater than

< Less than

= Greater than or equal to

<= Less than or equal to



Example:

SELECT *
FROM employees
WHERE salary >= 50000;


This returns employees whose salary is at least 50,000.

๐Ÿ”น 5. Equal To =

The = operator checks whether two values are equal.

SELECT *
FROM customers
WHERE city = 'Delhi';


Only records where city equals Delhi are returned.

๐Ÿ”น 6. Not Equal <>

You can retrieve records that don't match a value.

SELECT *
FROM customers
WHERE city <> 'Delhi';


This returns customers whose city isn't Delhi.

You may also see:

WHERE city != 'Delhi'


Both are commonly supported, although <> is the standard SQL operator.

๐Ÿ”น 7. Greater Than >

Example:

SELECT *
FROM orders
WHERE amount > 50000;


Returns orders above 50,000.

๐Ÿ”น 8. Less Than <

Example:

SELECT *
FROM products
WHERE price < 1000;


Returns products priced below 1,000.

๐Ÿ”น 9. Greater Than or Equal To >=

Example:

SELECT *
FROM employees
WHERE experience >= 5;


This includes employees with exactly 5 years as well as those with more than 5 years.

๐Ÿ”น 10. Less Than or Equal To <=

Example:

SELECT *
FROM products
WHERE price <= 500;


This includes products priced exactly at 500.

๐Ÿ”น 11. WHERE with Multiple Conditions

Real-world queries often require more than one condition.

For this, SQL provides logical operators:

โ€ข AND

โ€ข OR

โ€ข NOT

๐Ÿ”น 12. AND

AND means all conditions must be true.

Example:

SELECT *
FROM customers
WHERE city = 'Pune'
AND age > 30;


This returns customers who:

1.

Are from Pune

2.

Are older than 30

Both conditions must be satisfied.

๐Ÿ”น 13. OR

OR means at least one condition must be true.

Example:
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SELECT *
FROM customers
WHERE city = 'Pune'
OR city = 'Mumbai';


This returns customers from either Pune or Mumbai.

๐Ÿ”น 14. AND vs OR

Consider:

WHERE age > 30
AND city = 'Pune'


A customer must satisfy both conditions.

But:

WHERE age > 30
OR city = 'Pune'


A customer only needs to satisfy one or both conditions.

This difference is extremely important.

๐Ÿ”น 15. NOT

NOT reverses a condition.

Example:

SELECT *
FROM customers
WHERE NOT city = 'Pune';


This returns customers who aren't from Pune.

You can also commonly write:

SELECT *
FROM customers
WHERE city <> 'Pune';


๐Ÿ”น 16. Combining AND and OR

You can combine multiple logical operators.

Example:

SELECT *
FROM employees
WHERE department = 'Finance'
AND salary > 60000;


Another example:

SELECT *
FROM employees
WHERE department = 'Finance'
OR department = 'Analytics'
AND salary > 60000;


When conditions become complex, use parentheses to make your intended logic explicit.

For example:

SELECT *
FROM employees
WHERE
(department = 'Finance' OR department = 'Analytics')
AND salary > 60000;


This means:



Employees from Finance or Analytics who earn more than 60,000.



๐Ÿ”น 17. Why Parentheses Matter

Consider:

WHERE city = 'Pune'
OR city = 'Mumbai'
AND age > 30


SQL's logical evaluation rules can make this behave differently from what a beginner might expect.

A safer and clearer version is:

WHERE
(city = 'Pune' OR city = 'Mumbai')
AND age > 30;


This clearly communicates the intended logic.

Best practice:



Use parentheses whenever combining AND and OR in a complex condition.



๐Ÿ”น 18. WHERE with Dates

You can also filter dates.

Example:

SELECT *
FROM orders
WHERE order_date >= '2026-01-01';


This retrieves orders on or after January 1, 2026.

Another example:

SELECT *
FROM orders
WHERE order_date < '2026-07-01';


This retrieves orders before July 1, 2026.

Date syntax can vary slightly across database systems, so always consider the SQL dialect you're using.

๐Ÿ”น 19. Filtering a Date Range

Suppose you want orders during a particular period.

You can use:

SELECT *
FROM orders
WHERE order_date >= '2026-01-01'
AND order_date < '2026-04-01';


This retrieves orders from January through March.

Using a half-open range like this is particularly useful when working with timestamps because it avoids accidentally excluding records with time components.

๐Ÿ”น 20. BETWEEN

SQL provides BETWEEN for range filtering.

Example:

SELECT *
FROM products
WHERE price BETWEEN 1000 AND 5000;


BETWEEN is inclusive of both boundaries in standard SQL.

So this includes:

1000

and:

5000

as well as values between them.

๐Ÿ”น 21. BETWEEN with Dates

Example:

SELECT *
FROM orders
WHERE order_date BETWEEN '2026-01-01' AND '2026-01-31';


For a date-only column, this can be useful.

However, if order_date contains timestamps, using:

order_date >= '2026-01-01'
AND order_date < '2026-02-01'


is often safer because it includes the entire final day regardless of the timestamp.

๐Ÿ”น 22. IN Operator

Suppose you want customers from:

Pune

Mumbai

Delhi

You could write:

SELECT *
FROM customers
WHERE city = 'Pune'
OR city = 'Mumbai'
OR city = 'Delhi';
But IN makes this much cleaner:

SELECT *
FROM customers
WHERE city IN ('Pune', 'Mumbai', 'Delhi');


IN checks whether a value belongs to a specified list.

๐Ÿ”น 23. NOT IN

You can also exclude multiple values.

SELECT *
FROM customers
WHERE city NOT IN ('Pune', 'Mumbai');


This returns customers whose city isn't Pune or Mumbai.

๐Ÿ”น 24. LIKE

LIKE is used for pattern matching.

Suppose we want names beginning with A.

SELECT *
FROM customers
WHERE name LIKE 'A%';


Here:

% โ†’ Any sequence of characters

So this could match:

Alice

Amit

Ananya

๐Ÿ”น 25. LIKE with %

Example:

SELECT *
FROM customers
WHERE name LIKE '%an%';


This searches for names containing the sequence an.

The exact behavior can depend on database collation and case-sensitivity settings.

๐Ÿ”น 26. LIKE with _

The underscore _ generally represents exactly one character.

Example:

SELECT *
FROM products
WHERE product_code LIKE 'A_1';


This could match:

A11

AB1

AX1

But not:

A123

A1

because _ represents one character.

๐Ÿ”น 27. NULL Values

One of the most important concepts in SQL filtering is NULL.

NULL generally means:



Missing, unknown, or unavailable value.



It does not mean:

Zero

Empty string

False

For example:

customer_id name phone

101 Alice 9999999999

102 Bob NULL

Bob's phone number is missing or unknown.

๐Ÿ”น 28. Checking for NULL

You should not normally write:

WHERE phone = NULL


Instead, use:

SELECT *
FROM customers
WHERE phone IS NULL;


To find records where the value exists:

SELECT *
FROM customers
WHERE phone IS NOT NULL;


This is extremely important in Data Analytics.

๐Ÿ”น 29. WHERE and NULL Logic

Suppose:

WHERE salary > 50000


What happens when salary is NULL?

The condition isn't considered true.

The row won't be returned.

SQL uses three-valued logic involving:

TRUE

FALSE

UNKNOWN

This is one reason NULL handling requires special attention.

๐Ÿ”น 30. WHERE with SELECT

WHERE works together with SELECT.

Example:

SELECT
customer_id,
name,
city
FROM customers
WHERE city = 'Pune';


The query:

1.

Retrieves selected columns

2.

From the customers table

3.

Keeps only rows satisfying the condition

๐Ÿ”น 31. WHERE in Real-World Data Science

Imagine a transaction database containing millions of records.

A Data Scientist needs:



Successful transactions above โ‚น10,000 from January 2026 onward.



A query might look like:

SELECT
transaction_id,
customer_id,
transaction_date,
amount
FROM transactions
WHERE status = 'Success'
AND amount > 10000
AND transaction_date >= '2026-01-01';


This is much more efficient for analysis than extracting the entire table and filtering everything later in Python.

๐Ÿ”น 32. WHERE Before Python

A common Data Science workflow is:

Database โ†’ SQL โ†’ Filter/Transform โ†’ Python โ†’ Analysis โ†’ Model

For example:

SELECT
customer_id,
amount,
transaction_date
FROM transactions
WHERE status = 'Success';


Then load the result into Pandas:

import pandas as pd

df = pd.read_sql(query, connection)


SQL handles the database-side filtering, while Python can then handle deeper analysis.

๐Ÿ”น 33. Common Mistakes

โŒ Mistake 1: Using = with NULL

Incorrect:

WHERE phone = NULL;


Correct:

WHERE phone IS NULL;
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โŒ Mistake 2: Forgetting quotes around text

Incorrect:

WHERE city = Pune;


Correct:

WHERE city = 'Pune';


โŒ Mistake 3: Using AND when you mean OR

Incorrect if you want either city:

WHERE city = 'Pune'
AND city = 'Mumbai';


A single city value cannot normally be both at the same time.

Correct:

WHERE city = 'Pune'
OR city = 'Mumbai';


Or:

WHERE city IN ('Pune', 'Mumbai');


โŒ Mistake 4: Forgetting parentheses

For complex conditions, use parentheses:

WHERE
(city = 'Pune' OR city = 'Mumbai')
AND age > 30;


โŒ Mistake 5: Assuming BETWEEN excludes the boundaries

BETWEEN is generally inclusive.

๐Ÿ”น 34. Interview Questions

๐Ÿ’ก What is the purpose of WHERE?

WHERE filters rows based on a condition.

๐Ÿ’ก What is the difference between WHERE and SELECT?

SELECT โ†’ Determines what columns/expressions appear in the result.

WHERE โ†’ Determines which rows are included.

๐Ÿ’ก How do you check for NULL?

Use:

IS NULL

or:

IS NOT NULL

๐Ÿ’ก What is the difference between IN and OR?

IN provides a concise way to test whether a value matches any value in a list.

๐Ÿ’ก Is BETWEEN inclusive?

Yes, BETWEEN generally includes both boundary values.

๐ŸŽฏ Practice Questions

Q1. Write a query to retrieve employees whose salary is greater than 50,000.

Q2. Write a query to retrieve customers from Pune or Mumbai.

Q3. Write a query to retrieve products priced between 1,000 and 5,000.

Q4. Write a query to retrieve customers whose phone number is missing.

Q5. Write a query to retrieve orders where the status is Success and the amount is greater than 10,000.

๐ŸŽฏ Key Takeaways

โœ… WHERE is used to filter rows.

โœ… = checks equality.

โœ… <> and != can be used for not equal.

โœ… AND requires all specified conditions to be true.

โœ… OR requires at least one condition to be true.

โœ… IN is useful for matching multiple values.

โœ… BETWEEN is useful for ranges and is generally inclusive.

โœ… LIKE is used for pattern matching.

โœ… % represents a sequence of characters.

โœ… _ represents one character.

โœ… Use IS NULL and IS NOT NULL for NULL values.

โœ… Parentheses make complex AND/OR logic clearer and safer.

๐Ÿงญ Double Tap โค๏ธ For More
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Important Excel, Tableau, Statistics, SQL related Questions with answers

1. What are the common problems that data analysts encounter during analysis?

The common problems steps involved in any analytics project are:

Handling duplicate data
Collecting the meaningful right data at the right time
Handling data purging and storage problems
Making data secure and dealing with compliance issues

2. Explain the Type I and Type II errors in Statistics?

In Hypothesis testing, a Type I error occurs when the null hypothesis is rejected even if it is true. It is also known as a false positive.

A Type II error occurs when the null hypothesis is not rejected, even if it is false. It is also known as a false negative.

3. How do you make a dropdown list in MS Excel?

First, click on the Data tab that is present in the ribbon.
Under the Data Tools group, select Data Validation.
Then navigate to Settings > Allow > List.
Select the source you want to provide as a list array.

4. How do you subset or filter data in SQL?

To subset or filter data in SQL, we use WHERE and HAVING clauses which give us an option of including only the data matching certain conditions.

5. What is a Gantt Chart in Tableau?

A Gantt chart in Tableau depicts the progress of value over the period, i.e., it shows the duration of events. It consists of bars along with the time axis. The Gantt chart is mostly used as a project management tool where each bar is a measure of a task in the project
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๐Ÿš€ ๐—š๐—ผ๐—ผ๐—ด๐—น๐—ฒ ๐—ฃ๐—ฟ๐—ผ๐—ณ๐—ฒ๐˜€๐˜€๐—ถ๐—ผ๐—ป๐—ฎ๐—น ๐—–๐—ฒ๐—ฟ๐˜๐—ถ๐—ณ๐—ถ๐—ฐ๐—ฎ๐˜๐—ฒ๐˜€ ๐—ถ๐—ป ๐——๐—ฎ๐˜๐—ฎ ๐—”๐—ป๐—ฎ๐—น๐˜†๐˜๐—ถ๐—ฐ๐˜€ & ๐—”๐—œ! ๐Ÿ“Š

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๐Ÿ“Œ Save this post and share it with someone interested in Data Analytics or AI!
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How do you find rows where the phone number is missing?
Anonymous Quiz
8%
A) WHERE phone = NULL
22%
B) WHERE phone == NULL
67%
C) WHERE phone IS NULL
3%
D) WHERE phone IN NULL
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Which LIKE pattern finds names that begin with the letter A?
Anonymous Quiz
31%
A) LIKE '%A'
8%
B) LIKE '_A%'
47%
C) LIKE 'A%'
15%
D) LIKE '%A%'
โค1
๐—Ÿ๐—ฒ๐˜ƒ๐—ฒ๐—น ๐—จ๐—ฝ ๐—ฌ๐—ผ๐˜‚๐—ฟ ๐—ฆ๐—ธ๐—ถ๐—น๐—น๐˜€ ๐˜„๐—ถ๐˜๐—ต ๐—ง๐—ต๐—ฒ๐˜€๐—ฒ ๐—š๐—ฎ๐—บ๐—ฒ-๐—–๐—ต๐—ฎ๐—ป๐—ด๐—ถ๐—ป๐—ด ๐—–๐—ผ๐˜‚๐—ฟ๐˜€๐—ฒ๐˜€!
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Complete Data Analytics Mastery: From Basics to Advanced ๐Ÿš€

Begin your Data Analytics journey by mastering the fundamentals:
- Understanding Data Types and Formats
- Basics of Exploratory Data Analysis (EDA)
- Introduction to Data Cleaning Techniques
- Statistical Foundations for Data Analytics
- Data Visualization Essentials

Grasp these essentials in just a week to build a solid foundation in data analytics.

Once you're comfortable, dive into intermediate topics:
- Advanced Data Visualization (using tools like Tableau)
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- Regression Analysis
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Take another week to solidify these skills and enhance your ability to draw meaningful insights from data.

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Remember, mastery comes with hands-on experience:
- Work on a simple data analytics project
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Consistent practice and application of analytics techniques are the keys to becoming a data analytics pro.

Best platforms to learn:
- SQL courses with Certificate
- Freecodecamp Python Course
- 365DataScience
- Data Analyst Interview Questions
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Share your progress and insights with others in the data analytics community. Enjoy the fascinating journey into the realm of data analytics! ๐Ÿ‘ฉโ€๐Ÿ’ป๐Ÿ‘จโ€๐Ÿ’ป

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Like this post if it helps ๐Ÿ˜„โค๏ธ

ENJOY LEARNING ๐Ÿ‘๐Ÿ‘
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