What data type does id in sql belong to?

ID in SQL is usually an integer type, including INT, UNSIGNED INT, and BIGINT, or a char(36) character field. Consider expected value range, storage space, processing speed, and uniqueness requirements when selecting. INT or UNSIGNED INT are common choices, BIGINT for handling very large or small values, and CHAR(36) for storing unique identifiers such as UUIDs.

Data type of ID in SQL

In SQL, ID is generally an integer data Type , such as:

• Integer (INT): A signed 32-bit integer that can store from -2^31 (-2,147,483,648) to 2^ A value of 31-1 (2,147,483,647).
• UNSIGNED INT): An unsigned 32-bit integer that can store values ​​from 0 to 2^32-1 (4,294,967,295).

In addition, the ID can also be bigint or char(36) Type:

• bigint: A signed 64-bit integer that can store values ​​from -2^63 (-9,223,372,036,854,775,808) to 2^63-1 (9,223,372,036,854,775,807).
• char(36): A fixed-length character field that can store a string of 36 characters in length. Typically used to store a UUID or similar unique identifier.

Select the appropriate data type

You need to consider the following factors when selecting the id data type:

• Expected value Range: Determine the range of expected values ​​to select an appropriate data type.
• Storage space: Unsigned integers take up less storage space than signed integers.
• Processing speed: Integers are compared and manipulated faster than character fields.
• Uniqueness Requirements: UUID or CHAR(36) can be used to store unique identifiers.

Generally, INT or UNSIGNED INT are common choices for the id field. However, when you need to deal with very large or very small numbers or when uniqueness is required, BIGINT or CHAR(36) may be more appropriate.

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