🔥Apache Spark Architecture with RDD & DAG

 Here’s the complete explanation with SQL queries, outputs, and an extra "Explain" column to make it clearer.

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1️⃣ Using BETWEEN (Inclusive)

SELECT * 
FROM employees
WHERE experience_years BETWEEN 3 AND 7;

✅ Includes employees with 3, 4, 5, 6, and 7 years of experience.

Output Example:

employee_id	name	experience_years	Explain
101	Alice	3	Included (3 is in range)
102	Bob	4	Included (between 3 and 7)
103	Carol	5	Included (between 3 and 7)
104	David	6	Included (between 3 and 7)
105	Eve	7	Included (7 is in range)

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2️⃣ Using >= and <= (Inclusive, Explicit Condition)

SELECT * 
FROM employees
WHERE experience_years >= 3 AND experience_years <= 7;

✅ Same result as BETWEEN, but more flexible for modifications.

Output Example:

employee_id	name	experience_years	Explain
101	Alice	3	Included (3 is in range)
102	Bob	4	Included (between 3 and 7)
103	Carol	5	Included (between 3 and 7)
104	David	6	Included (between 3 and 7)
105	Eve	7	Included (7 is in range)

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3️⃣ Using > and < (Exclusive)

SELECT * 
FROM employees
WHERE experience_years > 3 AND experience_years < 7;

✅ Excludes employees with exactly 3 and 7 years of experience.

Output Example:

employee_id	name	experience_years	Explain
102	Bob	4	Included (greater than 3 and less than 7)
103	Carol	5	Included (greater than 3 and less than 7)
104	David	6	Included (greater than 3 and less than 7)

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Summary Table

Condition	Query Type	Includes 3 & 7?	Explain
✅ Inclusive Range	BETWEEN 3 AND 7	✅ Yes	Best when both boundaries must be included.
✅ Inclusive, Flexible	>= 3 AND <= 7	✅ Yes	When you may need to tweak conditions later.
❌ Exclusive Range	> 3 AND < 7	❌ No	Best when you need only the middle values.

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🔹 Use BETWEEN when you want a direct, simple range (inclusive).
🔹 Use >= and <= for more flexibility in modifying the range later.
🔹 Use > and < when you need to exclude the boundary values.

This should give you a crystal-clear understanding. Let me know if you need more details! 🚀😊