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HomeDatabaseMysql TutorialWhat is the difference between CHAR and VARCHAR in MySQL?

MySQL 中 CHAR 和 VARCHAR 有什么区别?

CHAR and VARCHAR are both ASCII character data types and are almost identical, but they differ in the stages of storing and retrieving data from the database. Following are some important differences between CHAR and VARCHAR in MySQL-

CHAR data type VARCHAR data type
The full name is CHARACTER

The full name is VARIABLE CHARACTER

It stores a fixed-length value padded with space characters to match the specified length

VARCHAR Converts a variable-length value to a 1-byte or 2-byte length Prefix without padding any characters

can hold up to 255 characters.

Can hold up to 65,535 characters.

#It uses static memory allocation.
mysql>create table emp(name CHAR(20));
Query OK, 0 rows affected (0.25
It uses dynamic memory allocation.
mysql>create table emp1(name VARCHAR(20));
Query OK, 0 rows affected (0.21

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