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📚 SUBSTRING

The SUBSTRING function is used in SQL to extract a part of a string starting at a specified position for a specified length.
It is useful for isolating specific sections of text from a larger string.

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🛠️ Basic Syntax

SELECT SUBSTRING(column_name, start_position, length)
FROM table_name;

• start_position specifies where to begin extraction (starting at 1).
• length defines how many characters to return.

Example

SELECT SUBSTRING(first_name, 1, 3) AS short_name
FROM employees;

• This query returns the first three characters of each employee’s first name.

Key Points

• Positions start at 1, not 0, in most SQL databases.
• If length exceeds the remaining characters, the function returns up to the end of the string.
• In some databases like MySQL, SUBSTRING() and SUBSTR() are interchangeable.

Additional Example

SELECT SUBSTRING(product_name, 5, 10) AS partial_product
FROM products;

• This query extracts 10 characters from product_name, starting at the 5th character.

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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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