How do I choose the right integer data type in MySQL for my needs?

MySQL Data Types: Tinyint, Smallint, Mediumint, Bigint, and Int

In MySQL, there are several integer data types that differ in their storage size and acceptable value ranges:

• Tinyint: 1 byte; signed (-128 to 127)/unsigned (0 to 255)
• Smallint: 2 bytes; signed (-32,768 to 32,767)/unsigned (0 to 65,535)
• Mediumint: 3 bytes; no unsigned type; signed (-8,388,608 to 8,388,607)
• Int/Integer: 4 bytes; signed (-2,147,483,648 to 2,147,483,647)/unsigned (0 to 4,294,967,295)
• Bigint: 8 bytes; signed (-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807)/unsigned (0 to 18,446,744,073,709,551,615)

When to Use These Data Types:

• Tinyint: For small integers representing values between -128 and 127, or 0 and 255 (unsigned). Typically used for boolean flags or other small enumerations.
• Smallint: For slightly larger integers within a range of -32,768 to 32,767 (signed) or 0 to 65,535 (unsigned). Useful for representing quantities such as year, day of week, or short dates.
• Mediumint: Used for integers within a narrower range of -8,388,608 to 8,388,607. Less commonly used but can be appropriate for specific cases with integer constraints in that range.
• Int/Integer: A general-purpose integer type, suitable for representing most integer values within a range of -2 billion to 2 billion.
• Bigint: For very large integers with a range of -9 quintillion to 9 quintillion (signed) or 0 to 18 quintillion (unsigned). Typically used for storing timestamps, large identifiers, or financial data.

In summary, choosing the appropriate data type depends on the specific range of values and the storage space required. Smaller data types like tinyint conserve space for small numbers, while larger types like bigint accommodate very large integer values.

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