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Shikha Gupta
Shikha Gupta

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Handling Data in SQL: Signed vs. Unsigned Types

In SQL, data types are essential for defining how data is stored in a database. One of the distinctions within numeric data types is signed vs. unsigned types, particularly for integer-based data. Here’s a breakdown of the difference:

  1. Signed Data Types

    • Range: These data types can store both positive and negative values.
    • Usage: If your data involves values that can be negative (such as temperatures, financial balances, etc.), you should use signed types.
    • Example:
      • TINYINT: -128 to 127
      • INT: -2,147,483,648 to 2,147,483,647
  2. Unsigned Data Types

    • Range: These data types can only store positive values and expand the range of possible values by shifting the negative range into the positive side.
    • Usage: Use unsigned types when the data will never have negative values (e.g., count of items, age, IDs).
    • Example:
      • TINYINT UNSIGNED: 0 to 255
      • INT UNSIGNED: 0 to 4,294,967,295

Key Differences

  • Storage: Both signed and unsigned types consume the same amount of storage (for instance, 4 bytes for an INT). The difference lies only in how that range is allocated between positive and negative values.
  • Use Case: Use unsigned types when you need a larger range of positive values and are certain there will be no negative numbers.
  • Default: If not specified, integer data types are signed by default.

Would you like to explore specific use cases or examples related to these types?

For more information click here:- https://www.youtube.com/watch?v=lvMVBCbVImg&t=302s

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