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📚 DATA TYPES

Data types in SQL define the kind of data that can be stored in a table column.
Choosing the correct data type ensures data accuracy, optimizes storage, and improves performance.

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🛠️ Basic Syntax

CREATE TABLE table_name (
    column1 INT,
    column2 VARCHAR(255),
    column3 DATE
);

• INT is used for integers.
• VARCHAR(n) is used for variable-length text up to n characters.
• DATE is used for storing calendar dates.

Example

CREATE TABLE employees (
    employee_id INT,
    first_name VARCHAR(50),
    hire_date DATE
);

• This creates an employees table with an integer ID, a string for first name, and a date for hire date.

Key Points

• Always choose the smallest data type that fits your data to save space.
• Text fields are typically VARCHAR, while fixed-length text can be CHAR.
• Dates and times should use specific types like DATE, TIME, or DATETIME.

Additional Example

CREATE TABLE products (
    product_id INT,
    product_name VARCHAR(100),
    price DECIMAL(10,2)
);

• This creates a products table where price allows numbers with up to 10 digits total and 2 after the decimal.

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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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