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📚 IS NULL

The IS NULL operator is used in SQL to test whether a column has a NULL value.
It helps find rows where data is missing or undefined.

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🛠️ Basic Syntax

SELECT column1, column2, ...
FROM table_name
WHERE column IS NULL;

• SELECT specifies the columns you want.
• FROM specifies the table.
• WHERE checks if a column value is NULL.

Example

SELECT * FROM users WHERE phone_number IS NULL;

• This query selects all users who do not have a phone number listed.

Key Points

• NULL means no value or unknown value, not zero or empty string.
• Use IS NULL to find missing values.
• Use IS NOT NULL to find where values do exist.

Additional Example

SELECT * FROM products
WHERE description IS NOT NULL;

• This query selects all products that have a description.

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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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🧠 Solution Code / Explanation

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

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