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📚 UPPER & LOWER

The UPPER and LOWER functions are used in SQL to convert the case of text.
They are helpful for standardizing data for searches, comparisons, or presentation.

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🛠️ Basic Syntax

SELECT UPPER(column_name)
FROM table_name;

SELECT LOWER(column_name)
FROM table_name;

• UPPER(column_name) converts all letters to uppercase.
• LOWER(column_name) converts all letters to lowercase.

Example

SELECT UPPER(first_name) AS uppercase_name
FROM employees;

• This query returns each employee's first name in all uppercase letters.

SELECT LOWER(email) AS normalized_email
FROM users;

• This query returns user emails in all lowercase.

Key Points

• Useful for case-insensitive searches or comparisons.
• Original data in the database remains unchanged unless an UPDATE is performed.
• Some databases have functions like INITCAP() to capitalize the first letter of each word (e.g., PostgreSQL).

Additional Example

SELECT LOWER(CONCAT(first_name, last_name)) AS combined_name
FROM customers;

• This query combines first and last names and converts the result to lowercase.

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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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