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📚 JOIN WITH COMPARISON

A JOIN with a comparison operator allows you to join tables based on more complex relationships than simple equality.
You can use operators like >, <, >=, <=, <>, or even BETWEEN in the ON clause.

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🛠️ Basic Syntax

SELECT columns
FROM table1
JOIN table2
ON table1.column_name operator table2.column_name;

• JOIN combines rows based on a specified condition, not just equality.
• The operator could be =, >, <, >=, <=, <>, or others.

Example

SELECT orders.order_id, customers.customer_name
FROM orders
JOIN customers
ON orders.customer_id = customers.customer_id;

• In this basic example, a standard equality operator is used to join orders to their customers.

Key Points

• Comparisons other than = are less common but useful for advanced queries.
• You can join tables based on date ranges, value comparisons, or custom logic.
• Always ensure that your comparison condition makes logical sense to avoid unexpected results.

Additional Example

SELECT employees.first_name, projects.project_name
FROM employees
JOIN projects
ON employees.experience_years >= projects.required_experience_years;

• This query matches employees to projects where their experience is greater than or equal to the project's required experience.

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🎥 Video Notes

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📝 Problem Description

Describe the problem, challenge, or topic discussed in a video related to SELECT FROM.
What concept was explained or what exercise was solved?

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DataBase Given

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💻 My SQL Code

-- Write your SQL code attempt or solution related to SQL COMMAND
SQL COMMAND

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🧠 Solution Code / Explanation

SQL COMMAND

Explanation - Explain what you learned, any key takeaways, or how you solved the problem related to COMMAND._

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