What is the difference between CHAR and VARCHAR data types in SQL?

Short answer: CHAR: A fixed-length string data type. It always reserves the same amount of space regardless of the string's length. Use case: When the length of the string is known and consistent. VARCHAR: A variable-length string data type. It only uses as much space as needed to store the string. Use case: When the string length can vary.

Example code

CREATE TABLE Example ( fixed_char CHAR(10), variable_char VARCHAR(10) );

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